Global Warming
  Will Human-Induced Climate
  Change Destroy the World?

                        By Rich Deem
            ...
Introduction
Introduction
• Is the world getting warmer?
Introduction
• Is the world getting warmer?
• If so, are the actions of mankind to
  blame for earth’s temperature
  incre...
Introduction
• Is the world getting warmer?
• If so, are the actions of mankind to
  blame for earth’s temperature
  incre...
Introduction
• Is the world getting warmer?
• If so, are the actions of mankind to
  blame for earth’s temperature
  incre...
History of Earth’s Climate
History of Earth’s Climate
• Earth formed ~4.6 billion years ago
History of Earth’s Climate
• Earth formed ~4.6 billion years ago
• Originally very hot
History of Earth’s Climate
• Earth formed ~4.6 billion years ago
• Originally very hot
• Sun’s energy output only 70% of
 ...
History of Earth’s Climate
• Earth formed ~4.6 billion years ago
• Originally very hot
• Sun’s energy output only 70% of
 ...
History of Earth’s Climate
• Earth formed ~4.6 billion years ago
• Originally very hot
• Sun’s energy output only 70% of
 ...
History of Earth’s Climate
History of Earth’s Climate
• Life appeared ~3.8 billion years ago
History of Earth’s Climate
• Life appeared ~3.8 billion years ago
• Photosynthesis began 3.5-2.5 billion
  years ago
History of Earth’s Climate
• Life appeared ~3.8 billion years ago
• Photosynthesis began 3.5-2.5 billion
  years ago
   P...
History of Earth’s Climate
• Life appeared ~3.8 billion years ago
• Photosynthesis began 3.5-2.5 billion
  years ago
   P...
History of Earth’s Climate
• Life appeared ~3.8 billion years ago
• Photosynthesis began 3.5-2.5 billion
  years ago
   P...
Earth’s Temperature
Earth’s Temperature

Sun
Earth’s Temperature

Sun

      Solar

      Energy
Solar Temperature
      Earth’s
      Energy
Sun
Earth’s Temperature

Sun

Solar

Energy
Earth’s Temperature

Sun


       Radiative
        Cooling
Earth’s Temperature
 Solar
Sun


Energy
Earth’s Temperature

Sun
Earth’s Temperature

Sun


 Solar

Energy
Earth’s Temperature

Sun
Greenhouse Effect
Sun   Greenhouse Effect
Sun   Greenhouse Effect
Earth’s Atmospheric Gases
Earth’s Atmospheric Gases
Nitrogen (N2)
Earth’s Atmospheric Gases
Nitrogen (N2)

Oxygen (O2)
Earth’s Atmospheric Gases
Nitrogen (N2)

Oxygen (O2)

Argon (Ar)
Earth’s Atmospheric Gases
Nitrogen (N2)

Oxygen (O2)         >99%
Argon (Ar)
Earth’s Atmospheric Gases
Nitrogen (N2)
                      Non-
Oxygen (O2)        Greenhouse
                     Gase...
Earth’s Atmospheric Gases
Nitrogen (N2)
                      Non-
Oxygen (O2)        Greenhouse
                     Gase...
Earth’s Atmospheric Gases
Nitrogen (N2)
                          Non-
Oxygen (O2)            Greenhouse
                 ...
Earth’s Atmospheric Gases
Nitrogen (N2)
                          Non-
Oxygen (O2)            Greenhouse
                 ...
Earth’s Atmospheric Gases
Nitrogen (N2)
                          Non-
Oxygen (O2)            Greenhouse
                 ...
Earth’s Atmospheric Gases
Nitrogen (N2)
                          Non-
Oxygen (O2)            Greenhouse
                 ...
Sun   Runaway Greenhouse Effect
Sun   Runaway Greenhouse Effect




                    Venus
Sun   Runaway Greenhouse Effect

• 97% carbon dioxide




                       Venus
Sun   Runaway Greenhouse Effect

• 97% carbon dioxide
• 3% nitrogen


                       Venus
Sun   Runaway Greenhouse Effect

• 97% carbon dioxide
• 3% nitrogen
• Water & sulfuric
  acid clouds
                     ...
Sun   Runaway Greenhouse Effect

• 97% carbon dioxide
• 3% nitrogen
• Water & sulfuric
  acid clouds
• Temperature:       ...
Carbon Dioxide
Carbon Dioxide Levels
            420

            370
CO2 (ppm)




            320

            270

            220
   ...
Carbon Dioxide Levels
            420

            370
CO2 (ppm)




            320

            270

            220
   ...
Carbon Dioxide Levels
            420
                                                  Muana Loa Readings
               ...
Worldwide Carbon Emissions
                           8
Carbon (109 metric tons)

                                  Total
...
Worldwide Carbon Emissions
                           8
Carbon (109 metric tons)

                                  Total
...
Worldwide Carbon Emissions
                           8
Carbon (109 metric tons)

                                  Total
...
Worldwide Carbon Emissions
                           8
Carbon (109 metric tons)

                                  Total
...
Worldwide Carbon Emissions
                           8
Carbon (109 metric tons)

                                  Total
...
Carbon (109 metric tons)
                           8
                               Annual Carbon Emissions

            ...
Carbon (109 metric tons)
                           8
                               Annual Carbon Emissions
             ...
Carbon (109 metric tons)
                           8
                               Annual Carbon Emissions
             ...
Future Carbon Dioxide Levels
Future Carbon Dioxide Levels
• Increasing CO2 emissions, especially in
  China and developing countries
Future Carbon Dioxide Levels
• Increasing CO2 emissions, especially in
  China and developing countries
• Likely to double...
Future Carbon Dioxide Levels
• Increasing CO2 emissions, especially in
  China and developing countries
• Likely to double...
Future Carbon Dioxide Levels
• Increasing CO2 emissions, especially in
  China and developing countries
• Likely to double...
Future Carbon Dioxide Levels
• Increasing CO2 emissions, especially in
  China and developing countries
• Likely to double...
Kyoto Protocol
Kyoto Protocol
• Adopted in 1997
Kyoto Protocol
• Adopted in 1997
• Cut CO2 emissions by 5% from 1990
  levels for 2008-2012
Kyoto Protocol
• Adopted in 1997
• Cut CO2 emissions by 5% from 1990
  levels for 2008-2012
• Symbolic only, since cuts wi...
Past Temperatures
Recorded Worldwide
                                       Temperatures
                          0.8

                    ...
Recorded Worldwide
                                       Temperatures
                          0.8

                    ...
Recorded Worldwide
                                       Temperatures
                          0.8

                    ...
Recorded Worldwide
                                       Temperatures
                          0.8

                    ...
Recorded Worldwide                    Flat
                                       Temperatures
                          0...
Historic Los Angeles
   Temperatures
Historic Los Angeles
                                           Temperatures
                        Annual Temperatures
 ...
Historic Los Angeles
                                           Temperatures
                        Annual Temperatures
 ...
Historic Los Angeles
                                           Temperatures
                        Annual Temperatures  ...
Historic Los Angeles
                                           Temperatures
                        Annual Temperatures  ...
Historic Los Angeles
                                           Temperatures
                        Annual Temperatures  ...
Historic Los Angeles
                                           Temperatures
                        Annual Temperatures  ...
2009 Temperature Changes
              Compared to 1951-1980




                       2009 Temperature Changes Compared ...
2009 Temperature Changes
              Compared to 1951-1980




                       2009 Temperature Changes Compared ...
2009 Temperature Changes
              Compared to 1951-1980




                       2009 Temperature Changes Compared ...
Past Temperatures Measurement
Past Temperatures Measurement
• Proxy – a method that approximates a
  particular measurement (e.g.,
  temperature)
Past Temperatures Measurement
• Proxy – a method that approximates a
  particular measurement (e.g.,
  temperature)
   Tr...
Past Temperatures Measurement
• Proxy – a method that approximates a
  particular measurement (e.g.,
  temperature)
   Tr...
Past Temperatures Measurement
• Proxy – a method that approximates a
  particular measurement (e.g.,
  temperature)
   Tr...
Past Temperatures Measurement
• Proxy – a method that approximates a
  particular measurement (e.g.,
  temperature)
     ...
Past Temperatures Measurement
• Proxy – a method that approximates a
  particular measurement (e.g.,
  temperature)
     ...
Past Temperatures Measurement
• Proxy – a method that approximates a
  particular measurement (e.g.,
  temperature)
     ...
Temperature History of the Earth
Temperature History of the Earth
• Little ice age (1400-1840) – 1°C cooler
Temperature History of the Earth
• Little ice age (1400-1840) – 1°C cooler
• Medieval warm period (800-1300) – 1°C
  warme...
Temperature History of the Earth
• Little ice age (1400-1840) – 1°C cooler
• Medieval warm period (800-1300) – 1°C
  warme...
Temperature History of the Earth
• Little ice age (1400-1840) – 1°C cooler
• Medieval warm period (800-1300) – 1°C
  warme...
Temperature History of the Earth
• Little ice age (1400-1840) – 1°C cooler
• Medieval warm period (800-1300) – 1°C
  warme...
Temperature History of the Earth
• Little ice age (1400-1840) – 1°C cooler
• Medieval warm period (800-1300) – 1°C
  warme...
Temperature History of the Earth
• Little ice age (1400-1840) – 1°C cooler
• Medieval warm period (800-1300) – 1°C
  warme...
Temperature History of the Earth
• Little ice age (1400-1840) – 1°C cooler
• Medieval warm period (800-1300) – 1°C
  warme...
Main Ocean Currents




                Adapted from IPCC SYR Figure 4-2
Main Ocean Currents




                Adapted from IPCC SYR Figure 4-2
Main Ocean Currents




                Adapted from IPCC SYR Figure 4-2
Main Ocean Currents




                Adapted from IPCC SYR Figure 4-2
Temperature History of the Earth
Temperature History of the Earth
• For the past 3 million years, the earth
  has been experiencing ~100,000 year
  long cy...
Temperature History of the Earth
• For the past 3 million years, the earth
  has been experiencing ~100,000 year
  long cy...
Orbital Parameters: Precession




       Apehelion      Perihelion
Orbital Parameters: Precession




       Apehelion      Perihelion
Orbital Parameters: Precession




       Apehelion      Perihelion
Orbital Parameters: Precession




       Apehelion      Perihelion
Orbital Parameters: Precession




       Apehelion      Perihelion
Orbital Parameters: Precession




       Apehelion      Perihelion
Orbital Parameters: Precession




       Apehelion      Perihelion
Orbital Parameters: Obliquity
Orbital Parameters: Obliquity
         22.5°
Orbital Parameters: Obliquity
Orbital Parameters: Obliquity
         24.5°
Orbital Parameters: Eccentricity
Orbital Parameters: Eccentricity




      Apehelion        Perihelion




                      Not to scale!
Orbital Parameters: Eccentricity
Maximum: 0.061




            Apehelion    Perihelion




                        Not to...
Orbital Parameters: Eccentricity
Maximum: 0.061


           Minimum: 0.005


            Apehelion        Perihelion




...
Orbital Parameters: Eccentricity
Maximum: 0.061




                        To Scale!
Orbital Parameters & Earth’s Climate




      1000 900 800 700 600 500 400 300 200 100 0
                        Age (kya)
Orbital Parameters & Earth’s Climate

Precession
  (22 ky)




        1000 900 800 700 600 500 400 300 200 100 0
        ...
Orbital Parameters & Earth’s Climate

Precession
  (22 ky)

 Obliquity
  (41 ky)




        1000 900 800 700 600 500 400 ...
Orbital Parameters & Earth’s Climate

Precession
  (22 ky)

  Obliquity
   (41 ky)
Eccentricity
  (100 ky)




          1...
Orbital Parameters & Earth’s Climate

 Precession
   (22 ky)

   Obliquity
    (41 ky)
Eccentricity
  (100 ky)



Temperat...
Orbital Parameters & Earth’s Climate

 Precession
   (22 ky)

   Obliquity
    (41 ky)
Eccentricity
  (100 ky)



Temperat...
Temperature History of the Earth
Temperature History of the Earth
• For the past 3 million years, the earth
  has been experiencing ~100,000 year
  long cy...
Temperature History of the Earth
• For the past 3 million years, the earth
  has been experiencing ~100,000 year
  long cy...
Younger Dryas Event
                   -25                             0.35




                                          ...
Younger Dryas Event
                   -25                             0.35




                                          ...
Younger Dryas Event
                   -25                             0.35




                                          ...
Younger Dryas Event
                   -25                             0.35




                                          ...
Younger Dryas Event
                   -25                             0.35




                                          ...
Younger Dryas Event
                   -25                                0.35
                           Younger




    ...
Younger Dryas Event
                   -25                                0.35
                           Younger




    ...
Younger Dryas Event
                   -25                                0.35
                           Younger




    ...
Younger Dryas Event
                   -25                                     0.35
                           Younger



...
Younger Dryas Event
                   -25                                         0.35
                           Younger...
Younger Dryas Event
               -8.0                             -34
                                   Younger
       ...
Younger Dryas Event
               -8.0                             -34
                                   Younger
       ...
Younger Dryas Event
               -8.0                             -34
                                   Younger
       ...
Temperature History of the Earth
Temperature History of the Earth
Middle Pliocene (3.15 to 2.85 million ya)
Temperature History of the Earth
Middle Pliocene (3.15 to 2.85 million ya)
• Temperatures: 2°C higher than today.
Temperature History of the Earth
Middle Pliocene (3.15 to 2.85 million ya)
• Temperatures: 2°C higher than today.
   20°C...
Temperature History of the Earth
Middle Pliocene (3.15 to 2.85 million ya)
• Temperatures: 2°C higher than today.
   20°C...
Temperature History of the Earth
Middle Pliocene (3.15 to 2.85 million ya)
• Temperatures: 2°C higher than today.
   20°C...
Temperature History of the Earth
Middle Pliocene (3.15 to 2.85 million ya)
• Temperatures: 2°C higher than today.
   20°C...
Temperature History of the Earth
Middle Pliocene (3.15 to 2.85 million ya)
• Temperatures: 2°C higher than today.
   20°C...
Temperature History of the Earth
Middle Pliocene (3.15 to 2.85 million ya)
• Temperatures: 2°C higher than today.
   20°C...
Temperature History of the Earth
Temperature History of the Earth
Eocene (41 million years ago)
Temperature History of the Earth
Eocene (41 million years ago)
• Opening of the Drake Passage
  (between South America and...
Temperature History of the Earth
Eocene (41 million years ago)
• Opening of the Drake Passage
  (between South America and...
Temperature History of the Earth
Eocene (41 million years ago)
• Opening of the Drake Passage
  (between South America and...
Temperature History of the Earth
Eocene (41 million years ago)
• Opening of the Drake Passage
  (between South America and...
Temperature History of the Earth
Temperature History of the Earth
Paleocene Thermal Maximum (55 mya)
Temperature History of the Earth
Paleocene Thermal Maximum (55 mya)
• Sea surface temperatures rose 5-8°C
Temperature History of the Earth
Paleocene Thermal Maximum (55 mya)
• Sea surface temperatures rose 5-8°C
• Causes
Temperature History of the Earth
Paleocene Thermal Maximum (55 mya)
• Sea surface temperatures rose 5-8°C
• Causes
   Inc...
Temperature History of the Earth
Paleocene Thermal Maximum (55 mya)
• Sea surface temperatures rose 5-8°C
• Causes
   Inc...
Temperature History of the Earth
Temperature History of the Earth
Mid-Cretaceous (120-90 mya)
Temperature History of the Earth
Mid-Cretaceous (120-90 mya)
• Much warmer
Temperature History of the Earth
Mid-Cretaceous (120-90 mya)
• Much warmer
• Breadfruit trees grew in Greenland
Temperature History of the Earth
Mid-Cretaceous (120-90 mya)
• Much warmer
• Breadfruit trees grew in Greenland
• Causes
Temperature History of the Earth
Mid-Cretaceous (120-90 mya)
• Much warmer
• Breadfruit trees grew in Greenland
• Causes
 ...
Temperature History of the Earth
Mid-Cretaceous (120-90 mya)
• Much warmer
• Breadfruit trees grew in Greenland
• Causes
 ...
A Compilation of Phanerozoic
      Atmospheric CO2 Records
                                                               ...
Recent Temperature
    Changes
“Hockey Stick” Controversy
                          0.6
Temperature Change (°C)



                                    Di...
“Hockey Stick” Controversy
                          0.6
Temperature Change (°C)



                                    Di...
“Hockey Stick” Controversy
                          0.6
Temperature Change (°C)



                                    Di...
“Hockey Stick” Controversy
                          0.6
Temperature Change (°C)



                                    Di...
“Hockey Stick” Controversy
                          0.6
Temperature Change (°C)



                                    Di...
The Problem with Tree Rings
                           0.3    Jones et al. 1998
Temperature Change (°C)



               ...
The Problem with Tree Rings
                           0.3    Jones et al. 1998
Temperature Change (°C)



               ...
The Problem with Tree Rings
                           0.3    Jones et al. 1998
Temperature Change (°C)



               ...
The Problem with Tree Rings
                           0.3    Jones et al. 1998
Temperature Change (°C)



               ...
The Problem with Tree Rings
                           0.3    Jones et al. 1998
Temperature Change (°C)



               ...
The Problem with Tree Rings
                           0.3    Jones et al. 1998
Temperature Change (°C)



               ...
The Problem with Tree Rings
                           0.3    Jones et al. 1998
Temperature Change (°C)



               ...
The Problem with Tree Rings
                           0.3    Jones et al. 1998
Temperature Change (°C)



               ...
The Problem with Tree Rings
                           0.3    Jones et al. 1998
Temperature Change (°C)



               ...
What Influences Tree Rings?
What Influences Tree Rings?
• Temperature
What Influences Tree Rings?
• Temperature
• Rainfall
What Influences Tree Rings?
• Temperature
• Rainfall
• Carbon dioxide concentration
Is the Hockey Stick Correct?
                          2
Temperature Change (°C)




                                     ...
Is the Hockey Stick Correct?
                          2
Temperature Change (°C)




                                     ...
Is the Hockey Stick Correct?
                          2
Temperature Change (°C)




                                     ...
Is the Hockey Stick Correct?
                          0.4
Temperature Change (°C)


                          0.2
       ...
Is the Hockey Stick Correct?
                          0.4
Temperature Change (°C)


                          0.2
       ...
Is the Hockey Stick Correct?
                          0.4
Temperature Change (°C)


                          0.2
       ...
Is the Hockey Stick Correct?
                          0.4
Temperature Change (°C)


                          0.2
       ...
Is the Hockey Stick Correct?
                          0.4
Temperature Change (°C)


                          0.2
       ...
Is the Hockey Stick Correct?
                          0.4
                                           Medieval Warm Period...
U.S. National Academy of
                                   Sciences: June 2006
                          0.6
Temperature ...
U.S. National Academy of
                                   Sciences: June 2006
                          0.6
Temperature ...
U.S. National Academy of
                                   Sciences: June 2006
                          0.6
Temperature ...
Atmospheric Temperatures
                                   Troposphere                Stratosphere
                      ...
Atmospheric Temperatures
                                   Troposphere                Stratosphere
                      ...
Atmospheric Temperatures
                                   Troposphere                Stratosphere
                      ...
CO2 Concentration Vs. Temperature
                       370




                                                         ...
CO2 Concentration Vs. Temperature
                       370




                                                         ...
CO2 Concentration Vs. Temperature
                       370




                                                         ...
Consequences of
Global Warming
Global Warming Primarily Impacts
                               the Northern Hemisphere
                                 N...
Global Warming Primarily Impacts
                               the Northern Hemisphere
                                 N...
Global Warming Primarily Impacts
                               the Northern Hemisphere
                                 N...
Global Warming Primarily Impacts
                               the Northern Hemisphere
                                 N...
Global Warming Primarily Impacts
                               the Northern Hemisphere
                                 N...
2009 Temperature Changes
              Compared to 1951-1980




-4.1   -4    -2   -1   -.5   -.2   .2   .5   1   2   4   ...
Ice Sheets Melting?
Ice Sheets Melting?
• GRACE (gravity measured by satellite)
  found melting of Antarctica equivalent
  to sea level rise o...
Ice Sheets Melting?
• GRACE (gravity measured by satellite)
  found melting of Antarctica equivalent
  to sea level rise o...
Ice Sheets Melting?
• GRACE (gravity measured by satellite)
  found melting of Antarctica equivalent
  to sea level rise o...
Ice Sheets Melting?
• GRACE (gravity measured by satellite)
  found melting of Antarctica equivalent
  to sea level rise o...
Ice Sheets Melting?
• GRACE (gravity measured by satellite)
  found melting of Antarctica equivalent
  to sea level rise o...
Melting Glaciers – Mt. Kilimanjaro
Melting Glaciers – Mt. Kilimanjaro
Changes in Antarctica Ice Mass
                 1000
                 800
                 600
Ice Mass (km3)




        ...
Changes in Antarctica Ice Mass
                 1000
                 800
                 600
Ice Mass (km3)




        ...
Rise in Sea Levels?
Rise in Sea Levels?
• Present rate is 1.8 ± 0.3 mm/yr (7.4 in/
  century)
Rise in Sea Levels?
• Present rate is 1.8 ± 0.3 mm/yr (7.4 in/
  century)
• Accelerating at a rate of 0.013 ± 0.006
  mm/y...
Rise in Sea Levels?
• Present rate is 1.8 ± 0.3 mm/yr (7.4 in/
  century)
• Accelerating at a rate of 0.013 ± 0.006
  mm/y...
Rise in Sea Levels?
• Present rate is 1.8 ± 0.3 mm/yr (7.4 in/
  century)
• Accelerating at a rate of 0.013 ± 0.006
  mm/y...
Changing Sea Levels
                          20
Relative Sea Level (cm)




                          10


              ...
Changing Sea Levels
                          20
Relative Sea Level (cm)




                          10


              ...
Changing Sea Levels
                          20
Relative Sea Level (cm)




                          10


              ...
Changing Sea Levels
                          20
Relative Sea Level (cm)




                          10


              ...
Changing Sea Levels
                          20
Relative Sea Level (cm)




                          10


              ...
Changing Sea Levels
                          20
Relative Sea Level (cm)




                          10


              ...
Changing Sea Levels
                          20




                                                                     ...
Sea Levels for 450,000 Years
                20                                             31




                       ...
Sea Levels for 450,000 Years
                20                                             31




                       ...
Sea Levels for 450,000 Years
                20                                             31




                       ...
Increase in Hurricanes?
Increase in Hurricanes?
• Two studies showed the total number
  of hurricanes has not changed
Increase in Hurricanes?
• Two studies showed the total number
  of hurricanes has not changed
• However, the intensity of ...
Increase in Hurricanes?
• Two studies showed the total number
  of hurricanes has not changed
• However, the intensity of ...
Increase in Hurricanes?
• Two studies showed the total number
  of hurricanes has not changed
• However, the intensity of ...
Increase in Hurricanes?
                      15
                                Data Unreliable
SST/SPDI (meters3/sec2)

...
Increase in Hurricanes?
                      15
                                Data Unreliable
SST/SPDI (meters3/sec2)

...
Increase in Hurricanes?
                      15
                                Data Unreliable
SST/SPDI (meters3/sec2)

...
Increase in Hurricanes?
How Much Temperature
     Increase?
How Much Temperature
          Increase?
• Some models propose up to 9°C
  increase this century
How Much Temperature
          Increase?
• Some models propose up to 9°C
  increase this century
• Two studies put the min...
How Much Temperature
          Increase?
• Some models propose up to 9°C
  increase this century
• Two studies put the min...
Wildlife Effects
Wildlife Effects
• Polar Bears
Wildlife Effects
• Polar Bears
   Require pack ice to live
Wildlife Effects
• Polar Bears
   Require pack ice to live
   Might eventually go extinct in the wild
Wildlife Effects
• Polar Bears
   Require pack ice to live
   Might eventually go extinct in the wild
• Sea turtles
Wildlife Effects
• Polar Bears
   Require pack ice to live
   Might eventually go extinct in the wild
• Sea turtles
   ...
Wildlife Effects
• Polar Bears
   Require pack ice to live
   Might eventually go extinct in the wild
• Sea turtles
   ...
Wildlife Effects
• Polar Bears
   Require pack ice to live
   Might eventually go extinct in the wild
• Sea turtles
   ...
Effect on Humans
Effect on Humans
• Fewer deaths from cold, more from
  heat
Effect on Humans
• Fewer deaths from cold, more from
  heat
• Decreased thermohaline circulation
   Cooler temperatures i...
Effect on Humans
• Fewer deaths from cold, more from
  heat
• Decreased thermohaline circulation
   Cooler temperatures i...
Effect on Humans
• Fewer deaths from cold, more from
  heat
• Decreased thermohaline circulation
   Cooler temperatures i...
Potential Worldwide Precipitation
            Changes




  -50   -20   -10   -5   5   10   20   50
Potential Worldwide Precipitation
            Changes




  -50   -20   -10   -5   5   10   20   50
Potential Worldwide Precipitation
            Changes




  -50   -20   -10   -5   5   10   20   50
Potential Worldwide Precipitation
            Changes




  -50   -20   -10   -5   5   10   20   50
Potential Worldwide Precipitation
            Changes




  -50   -20   -10   -5   5   10   20   50
Potential Worldwide Precipitation
            Changes




  -50   -20   -10   -5   5   10   20   50
Potential Worldwide Precipitation
            Changes




  -50   -20   -10   -5   5   10   20   50
Potential Worldwide Precipitation
            Changes




  -50   -20   -10   -5   5   10   20   50
Potential Worldwide Precipitation
            Changes




  -50   -20   -10   -5   5   10   20   50
Potential Worldwide Precipitation
            Changes




  -50   -20   -10   -5   5   10   20   50
Drought in Africa
Drought in Africa
Lake Faguibine
Drought in Africa
Lake Faguibine       Lake Chad
Cost to Stabilize CO2
                                          Concentrations
                               1800
Cost (T...
Cost to Stabilize CO2
                                          Concentrations
                               1800
Cost (T...
Possible Solutions to
  Global Warming
Mitigation of Global Warming
Mitigation of Global Warming
• Conservation
Mitigation of Global Warming
• Conservation
   Reduce energy needs
Mitigation of Global Warming
• Conservation
   Reduce energy needs
Mitigation of Global Warming
• Conservation
   Reduce energy needs
   Recycling
Mitigation of Global Warming
• Conservation
   Reduce energy needs
   Recycling
• Alternate energy sources
Mitigation of Global Warming
• Conservation
   Reduce energy needs
   Recycling
• Alternate energy sources
   Nuclear
Mitigation of Global Warming
• Conservation
   Reduce energy needs
   Recycling
• Alternate energy sources
   Nuclear
 ...
Mitigation of Global Warming
• Conservation
   Reduce energy needs
   Recycling
• Alternate energy sources
   Nuclear
 ...
Mitigation of Global Warming
• Conservation
   Reduce energy needs
   Recycling
• Alternate energy sources
     Nuclear...
Mitigation of Global Warming
• Conservation
   Reduce energy needs
   Recycling
• Alternate energy sources
     Nuclear...
Mitigation of Global Warming
• Conservation
   Reduce energy needs
   Recycling
• Alternate energy sources
     Nuclear...
Storage of CO2 in Geological Formations




                            Adapted from IPCC SRCCS Figure TS-7
Storage of CO2 in Geological Formations
1.    Depleted oil and gas reservoirs




                                        ...
Storage of CO2 in Geological Formations
1.    Depleted oil and gas reservoirs
2.    CO2 in enhanced oil and gas recovery

...
Storage of CO2 in Geological Formations
1.    Depleted oil and gas reservoirs
2.    CO2 in enhanced oil and gas recovery
3...
Storage of CO2 in Geological Formations
1.    Depleted oil and gas reservoirs
2.    CO2 in enhanced oil and gas recovery
3...
Storage of CO2 in Geological Formations
1.    Depleted oil and gas reservoirs
2.    CO2 in enhanced oil and gas recovery
3...
Global Warming Myths
Global Warming Has Stopped?
                          0.8
Δ Mean Temperature (°C)




                          0.6

     ...
Global Warming Has Stopped?
                          0.8
Δ Mean Temperature (°C)




                          0.6

     ...
Global Warming Has Stopped?
                          0.8                             1366.8
                             ...
Global Warming Has Stopped?
                          0.8                             1366.8
                             ...
Global Warming Has Stopped?
                          0.8                             1366.8
                             ...
Global Warming
Global Warming
Global Warming
Global Warming
Global Warming
Global Warming
Global Warming
Global Warming
Global Warming
Global Warming
Global Warming
Global Warming
Global Warming
Global Warming
Global Warming
Global Warming
Global Warming
Global Warming
Global Warming
Global Warming
Global Warming
Global Warming
Global Warming
Global Warming
Global Warming
Global Warming
Global Warming
Global Warming
Global Warming
Global Warming
Global Warming
Global Warming
Global Warming
Global Warming
Global Warming
Global Warming
Global Warming
Global Warming
Global Warming
Global Warming
Global Warming
Global Warming
Global Warming
Global Warming
Global Warming
Global Warming
Global Warming
Global Warming
Global Warming
Global Warming
Global Warming
Global Warming
Global Warming
Global Warming
Global Warming
Global Warming
Global Warming
Global Warming
Global Warming
Global Warming
Global Warming
Global Warming
Global Warming
Global Warming
Global Warming
Global Warming
Global Warming
Global Warming
Global Warming
Global Warming
Global Warming
Global Warming
Upcoming SlideShare
Loading in...5
×

Global Warming

1,462

Published on

0 Comments
1 Like
Statistics
Notes
  • Be the first to comment

No Downloads
Views
Total Views
1,462
On Slideshare
0
From Embeds
0
Number of Embeds
0
Actions
Shares
0
Downloads
58
Comments
0
Likes
1
Embeds 0
No embeds

No notes for slide
  • This slideshow present an overview of global warming issues, last updated 8/11/2006. A more detailed analysis of global warming issues is available at http://www.godandscience.org/apologetics/global_warming.html, including a printable PDF version. 
  • In examining global warming, we will be looking at questions such as 
    Is the world getting warmer? 
    If so, are the actions of mankind to blame for earth’s temperature increases? 
    What can or should be done about global warming? 
    Are the potential resolutions to global warming worth the cost to implement them? 
  • In examining global warming, we will be looking at questions such as 
    Is the world getting warmer? 
    If so, are the actions of mankind to blame for earth’s temperature increases? 
    What can or should be done about global warming? 
    Are the potential resolutions to global warming worth the cost to implement them? 
  • In examining global warming, we will be looking at questions such as 
    Is the world getting warmer? 
    If so, are the actions of mankind to blame for earth’s temperature increases? 
    What can or should be done about global warming? 
    Are the potential resolutions to global warming worth the cost to implement them? 
  • In examining global warming, we will be looking at questions such as 
    Is the world getting warmer? 
    If so, are the actions of mankind to blame for earth’s temperature increases? 
    What can or should be done about global warming? 
    Are the potential resolutions to global warming worth the cost to implement them? 
  • This is a big picture examination of the earth’s climate 
    The Earth was formed around 4.6 billion years ago 
    And was originally very hot 
    However, the Sun’s energy output was only 70% of what it is presently 
    Liquid water was present on the surface around 4.3 billion years ago, according to zircon dating 
    However, much of earth’s early history was erased during late heavy bombardment, which took place around 3.9 billion years ago 
  • This is a big picture examination of the earth’s climate 
    The Earth was formed around 4.6 billion years ago 
    And was originally very hot 
    However, the Sun’s energy output was only 70% of what it is presently 
    Liquid water was present on the surface around 4.3 billion years ago, according to zircon dating 
    However, much of earth’s early history was erased during late heavy bombardment, which took place around 3.9 billion years ago 
  • This is a big picture examination of the earth’s climate 
    The Earth was formed around 4.6 billion years ago 
    And was originally very hot 
    However, the Sun’s energy output was only 70% of what it is presently 
    Liquid water was present on the surface around 4.3 billion years ago, according to zircon dating 
    However, much of earth’s early history was erased during late heavy bombardment, which took place around 3.9 billion years ago 
  • This is a big picture examination of the earth’s climate 
    The Earth was formed around 4.6 billion years ago 
    And was originally very hot 
    However, the Sun’s energy output was only 70% of what it is presently 
    Liquid water was present on the surface around 4.3 billion years ago, according to zircon dating 
    However, much of earth’s early history was erased during late heavy bombardment, which took place around 3.9 billion years ago 
  • This is a big picture examination of the earth’s climate 
    The Earth was formed around 4.6 billion years ago 
    And was originally very hot 
    However, the Sun’s energy output was only 70% of what it is presently 
    Liquid water was present on the surface around 4.3 billion years ago, according to zircon dating 
    However, much of earth’s early history was erased during late heavy bombardment, which took place around 3.9 billion years ago 

  • The first life forms appeared ~3.8 billion years ago 
    Photosynthesis began 3.5-2.5 billion years ago, 
    which produced oxygen and removed carbon dioxide and methane, which are greenhouse gases, from the atmosphere 
    As a result, the Earth went through periods of cooling, commonly referred to as “Snowball Earth” and subsequent warming 
    Earth began its current cycles of glacial and interglacial periods around 3 million years ago 

  • The first life forms appeared ~3.8 billion years ago 
    Photosynthesis began 3.5-2.5 billion years ago, 
    which produced oxygen and removed carbon dioxide and methane, which are greenhouse gases, from the atmosphere 
    As a result, the Earth went through periods of cooling, commonly referred to as “Snowball Earth” and subsequent warming 
    Earth began its current cycles of glacial and interglacial periods around 3 million years ago 

  • The first life forms appeared ~3.8 billion years ago 
    Photosynthesis began 3.5-2.5 billion years ago, 
    which produced oxygen and removed carbon dioxide and methane, which are greenhouse gases, from the atmosphere 
    As a result, the Earth went through periods of cooling, commonly referred to as “Snowball Earth” and subsequent warming 
    Earth began its current cycles of glacial and interglacial periods around 3 million years ago 

  • The first life forms appeared ~3.8 billion years ago 
    Photosynthesis began 3.5-2.5 billion years ago, 
    which produced oxygen and removed carbon dioxide and methane, which are greenhouse gases, from the atmosphere 
    As a result, the Earth went through periods of cooling, commonly referred to as “Snowball Earth” and subsequent warming 
    Earth began its current cycles of glacial and interglacial periods around 3 million years ago 

  • The first life forms appeared ~3.8 billion years ago 
    Photosynthesis began 3.5-2.5 billion years ago, 
    which produced oxygen and removed carbon dioxide and methane, which are greenhouse gases, from the atmosphere 
    As a result, the Earth went through periods of cooling, commonly referred to as “Snowball Earth” and subsequent warming 
    Earth began its current cycles of glacial and interglacial periods around 3 million years ago 
  • The temperature of the earth is directly related to the energy input from the Sun.  Some of the Sun’s energy is reflected by clouds.  Other is reflected by ice. The remainder is absorbed by the earth. 
  • The temperature of the earth is directly related to the energy input from the Sun.  Some of the Sun’s energy is reflected by clouds.  Other is reflected by ice. The remainder is absorbed by the earth. 
  • The temperature of the earth is directly related to the energy input from the Sun.  Some of the Sun’s energy is reflected by clouds.  Other is reflected by ice. The remainder is absorbed by the earth. 
  • The temperature of the earth is directly related to the energy input from the Sun.  Some of the Sun’s energy is reflected by clouds.  Other is reflected by ice. The remainder is absorbed by the earth. 
  • The temperature of the earth is directly related to the energy input from the Sun.  Some of the Sun’s energy is reflected by clouds.  Other is reflected by ice. The remainder is absorbed by the earth. 
  • The temperature of the earth is directly related to the energy input from the Sun.  Some of the Sun’s energy is reflected by clouds.  Other is reflected by ice. The remainder is absorbed by the earth. 
  • The temperature of the earth is directly related to the energy input from the Sun.  Some of the Sun’s energy is reflected by clouds.  Other is reflected by ice. The remainder is absorbed by the earth. 
  •  If amount of solar energy absorbed by the earth is equal to the amount radiated back into space, the earth remains at a constant temperature. 
  •  If amount of solar energy absorbed by the earth is equal to the amount radiated back into space, the earth remains at a constant temperature. 
  •  If amount of solar energy absorbed by the earth is equal to the amount radiated back into space, the earth remains at a constant temperature. 
  •  However, if the amount of solar energy is greater than the amount radiated, then the earth heats up. 
  •  However, if the amount of solar energy is greater than the amount radiated, then the earth heats up. 
  •  However, if the amount of solar energy is greater than the amount radiated, then the earth heats up. 
  •  However, if the amount of solar energy is greater than the amount radiated, then the earth heats up. 
  •  However, if the amount of solar energy is greater than the amount radiated, then the earth heats up. 
  •  If the amount of solar energy is less than the amount radiated, then the earth cools down. 
  •  If the amount of solar energy is less than the amount radiated, then the earth cools down. 
  •  If the amount of solar energy is less than the amount radiated, then the earth cools down. 
  •  If the amount of solar energy is less than the amount radiated, then the earth cools down. 
  •  If the amount of solar energy is less than the amount radiated, then the earth cools down. 
  •  If the amount of solar energy is less than the amount radiated, then the earth cools down. 
  • To a certain degree, the earth acts like a greenhouse.  Energy from the Sun penetrates the glass of a greenhouse and warms the air and objects within the greenhouse. The same glass slows the heat from escaping, resulting in much higher temperatures within the greenhouse than outside it. 
  • To a certain degree, the earth acts like a greenhouse.  Energy from the Sun penetrates the glass of a greenhouse and warms the air and objects within the greenhouse. The same glass slows the heat from escaping, resulting in much higher temperatures within the greenhouse than outside it. 
  • Likewise, the earth’s atmospheric gases affect the ability of the earth to radiate the Sun’s energy back into space.  Nitrogen,  Oxygen and  Argon  make up >99% of the earth’s atmospheric gases  and are non-greenhouse gases.  Water,  Carbon Dioxide,  and Methane  make up <1% of the earth’s atmosphere,  but are greenhouse gases, since they cause the earth to retain heat. 
  • Likewise, the earth’s atmospheric gases affect the ability of the earth to radiate the Sun’s energy back into space.  Nitrogen,  Oxygen and  Argon  make up >99% of the earth’s atmospheric gases  and are non-greenhouse gases.  Water,  Carbon Dioxide,  and Methane  make up <1% of the earth’s atmosphere,  but are greenhouse gases, since they cause the earth to retain heat. 
  • Likewise, the earth’s atmospheric gases affect the ability of the earth to radiate the Sun’s energy back into space.  Nitrogen,  Oxygen and  Argon  make up >99% of the earth’s atmospheric gases  and are non-greenhouse gases.  Water,  Carbon Dioxide,  and Methane  make up <1% of the earth’s atmosphere,  but are greenhouse gases, since they cause the earth to retain heat. 
  • Likewise, the earth’s atmospheric gases affect the ability of the earth to radiate the Sun’s energy back into space.  Nitrogen,  Oxygen and  Argon  make up >99% of the earth’s atmospheric gases  and are non-greenhouse gases.  Water,  Carbon Dioxide,  and Methane  make up <1% of the earth’s atmosphere,  but are greenhouse gases, since they cause the earth to retain heat. 
  • Likewise, the earth’s atmospheric gases affect the ability of the earth to radiate the Sun’s energy back into space.  Nitrogen,  Oxygen and  Argon  make up >99% of the earth’s atmospheric gases  and are non-greenhouse gases.  Water,  Carbon Dioxide,  and Methane  make up <1% of the earth’s atmosphere,  but are greenhouse gases, since they cause the earth to retain heat. 
  • Likewise, the earth’s atmospheric gases affect the ability of the earth to radiate the Sun’s energy back into space.  Nitrogen,  Oxygen and  Argon  make up >99% of the earth’s atmospheric gases  and are non-greenhouse gases.  Water,  Carbon Dioxide,  and Methane  make up <1% of the earth’s atmosphere,  but are greenhouse gases, since they cause the earth to retain heat. 
  • Likewise, the earth’s atmospheric gases affect the ability of the earth to radiate the Sun’s energy back into space.  Nitrogen,  Oxygen and  Argon  make up >99% of the earth’s atmospheric gases  and are non-greenhouse gases.  Water,  Carbon Dioxide,  and Methane  make up <1% of the earth’s atmosphere,  but are greenhouse gases, since they cause the earth to retain heat. 
  • Likewise, the earth’s atmospheric gases affect the ability of the earth to radiate the Sun’s energy back into space.  Nitrogen,  Oxygen and  Argon  make up >99% of the earth’s atmospheric gases  and are non-greenhouse gases.  Water,  Carbon Dioxide,  and Methane  make up <1% of the earth’s atmosphere,  but are greenhouse gases, since they cause the earth to retain heat. 
  • Likewise, the earth’s atmospheric gases affect the ability of the earth to radiate the Sun’s energy back into space.  Nitrogen,  Oxygen and  Argon  make up >99% of the earth’s atmospheric gases  and are non-greenhouse gases.  Water,  Carbon Dioxide,  and Methane  make up <1% of the earth’s atmosphere,  but are greenhouse gases, since they cause the earth to retain heat. 
  • Likewise, the earth’s atmospheric gases affect the ability of the earth to radiate the Sun’s energy back into space.  Nitrogen,  Oxygen and  Argon  make up >99% of the earth’s atmospheric gases  and are non-greenhouse gases.  Water,  Carbon Dioxide,  and Methane  make up <1% of the earth’s atmosphere,  but are greenhouse gases, since they cause the earth to retain heat. 
  • Likewise, the earth’s atmospheric gases affect the ability of the earth to radiate the Sun’s energy back into space.  Nitrogen,  Oxygen and  Argon  make up >99% of the earth’s atmospheric gases  and are non-greenhouse gases.  Water,  Carbon Dioxide,  and Methane  make up <1% of the earth’s atmosphere,  but are greenhouse gases, since they cause the earth to retain heat. 
  • Likewise, the earth’s atmospheric gases affect the ability of the earth to radiate the Sun’s energy back into space.  Nitrogen,  Oxygen and  Argon  make up >99% of the earth’s atmospheric gases  and are non-greenhouse gases.  Water,  Carbon Dioxide,  and Methane  make up <1% of the earth’s atmosphere,  but are greenhouse gases, since they cause the earth to retain heat. 
  • Likewise, the earth’s atmospheric gases affect the ability of the earth to radiate the Sun’s energy back into space.  Nitrogen,  Oxygen and  Argon  make up >99% of the earth’s atmospheric gases  and are non-greenhouse gases.  Water,  Carbon Dioxide,  and Methane  make up <1% of the earth’s atmosphere,  but are greenhouse gases, since they cause the earth to retain heat. 
  • Likewise, the earth’s atmospheric gases affect the ability of the earth to radiate the Sun’s energy back into space.  Nitrogen,  Oxygen and  Argon  make up >99% of the earth’s atmospheric gases  and are non-greenhouse gases.  Water,  Carbon Dioxide,  and Methane  make up <1% of the earth’s atmosphere,  but are greenhouse gases, since they cause the earth to retain heat. 
  • A dramatic example of the Greenhouse effect can be seen with the planet Venus. Venus’s atmosphere consists of  97% carbon dioxide and  3% nitrogen. In addition, the surface is covered by  dense clouds of water and sulfuric acid. The combination of greenhouse gases results in a  surface temperature of 860°F – even hotter than the planet Mercury, which is nearest the Sun. 
  • A dramatic example of the Greenhouse effect can be seen with the planet Venus. Venus’s atmosphere consists of  97% carbon dioxide and  3% nitrogen. In addition, the surface is covered by  dense clouds of water and sulfuric acid. The combination of greenhouse gases results in a  surface temperature of 860°F – even hotter than the planet Mercury, which is nearest the Sun. 
  • A dramatic example of the Greenhouse effect can be seen with the planet Venus. Venus’s atmosphere consists of  97% carbon dioxide and  3% nitrogen. In addition, the surface is covered by  dense clouds of water and sulfuric acid. The combination of greenhouse gases results in a  surface temperature of 860°F – even hotter than the planet Mercury, which is nearest the Sun. 
  • A dramatic example of the Greenhouse effect can be seen with the planet Venus. Venus’s atmosphere consists of  97% carbon dioxide and  3% nitrogen. In addition, the surface is covered by  dense clouds of water and sulfuric acid. The combination of greenhouse gases results in a  surface temperature of 860°F – even hotter than the planet Mercury, which is nearest the Sun. 
  • A dramatic example of the Greenhouse effect can be seen with the planet Venus. Venus’s atmosphere consists of  97% carbon dioxide and  3% nitrogen. In addition, the surface is covered by  dense clouds of water and sulfuric acid. The combination of greenhouse gases results in a  surface temperature of 860°F – even hotter than the planet Mercury, which is nearest the Sun. 
  • 
  • This graph shows the amount of  carbon dioxide in the atmosphere for the last 650,000 years, as determined through Antarctic ice cores.  You will notice the  large spike at the end of the graph, which can be seen in the  inset as a dramatic increase in atmospheric carbon dioxide over the last 45 years. 
  • This graph shows the amount of  carbon dioxide in the atmosphere for the last 650,000 years, as determined through Antarctic ice cores.  You will notice the  large spike at the end of the graph, which can be seen in the  inset as a dramatic increase in atmospheric carbon dioxide over the last 45 years. 
  • This graph shows the amount of  carbon dioxide in the atmosphere for the last 650,000 years, as determined through Antarctic ice cores.  You will notice the  large spike at the end of the graph, which can be seen in the  inset as a dramatic increase in atmospheric carbon dioxide over the last 45 years. 
  • This graph shows the amount of  carbon dioxide in the atmosphere for the last 650,000 years, as determined through Antarctic ice cores.  You will notice the  large spike at the end of the graph, which can be seen in the  inset as a dramatic increase in atmospheric carbon dioxide over the last 45 years. 
  • This spike is due to the exponential increase in the use of fossil fuels over the last 150 years. Shown here are emissions of carbon from  gas,  solid,  liquid fuels, and  the total carbon emissions. 
  • This spike is due to the exponential increase in the use of fossil fuels over the last 150 years. Shown here are emissions of carbon from  gas,  solid,  liquid fuels, and  the total carbon emissions. 
  • This spike is due to the exponential increase in the use of fossil fuels over the last 150 years. Shown here are emissions of carbon from  gas,  solid,  liquid fuels, and  the total carbon emissions. 
  • This spike is due to the exponential increase in the use of fossil fuels over the last 150 years. Shown here are emissions of carbon from  gas,  solid,  liquid fuels, and  the total carbon emissions. 
  • Despite this rapid increase in  carbon emissions, only about  half the carbon can be detected in the atmosphere. The remainder of the carbon dioxide is being dissolved in the oceans or incorporated into trees. 
  • Despite this rapid increase in  carbon emissions, only about  half the carbon can be detected in the atmosphere. The remainder of the carbon dioxide is being dissolved in the oceans or incorporated into trees. 
  • Future Carbon Emissions 
    will probably increase, especially in China and developing countries 
    This will result in a likely doubling of carbon dioxide levels within 150 years, due to 
    Increased coal usage 
    And increased natural gas usage, 
    although petroleum usage is likely to decrease due to increased cost and decreasing supply 
  • Future Carbon Emissions 
    will probably increase, especially in China and developing countries 
    This will result in a likely doubling of carbon dioxide levels within 150 years, due to 
    Increased coal usage 
    And increased natural gas usage, 
    although petroleum usage is likely to decrease due to increased cost and decreasing supply 
  • Future Carbon Emissions 
    will probably increase, especially in China and developing countries 
    This will result in a likely doubling of carbon dioxide levels within 150 years, due to 
    Increased coal usage 
    And increased natural gas usage, 
    although petroleum usage is likely to decrease due to increased cost and decreasing supply 
  • Future Carbon Emissions 
    will probably increase, especially in China and developing countries 
    This will result in a likely doubling of carbon dioxide levels within 150 years, due to 
    Increased coal usage 
    And increased natural gas usage, 
    although petroleum usage is likely to decrease due to increased cost and decreasing supply 
  • Future Carbon Emissions 
    will probably increase, especially in China and developing countries 
    This will result in a likely doubling of carbon dioxide levels within 150 years, due to 
    Increased coal usage 
    And increased natural gas usage, 
    although petroleum usage is likely to decrease due to increased cost and decreasing supply 
  • In an effort to reduce carbon emissions, the Kyoto protocol 
    was adopted in 1997. 
    It proposed to cut CO2 emissions by 5% from 1990 levels for period of 2008-2012 
    However, such minor cuts would be symbolic only, since such cuts would not significantly impact global warming 
  • In an effort to reduce carbon emissions, the Kyoto protocol 
    was adopted in 1997. 
    It proposed to cut CO2 emissions by 5% from 1990 levels for period of 2008-2012 
    However, such minor cuts would be symbolic only, since such cuts would not significantly impact global warming 
  • In an effort to reduce carbon emissions, the Kyoto protocol 
    was adopted in 1997. 
    It proposed to cut CO2 emissions by 5% from 1990 levels for period of 2008-2012 
    However, such minor cuts would be symbolic only, since such cuts would not significantly impact global warming 
  • 
  •  This is a graph of the change in worldwide temperatures over the last 130 years. Although the trend is decidedly upward, there are periods when temperatures are  flat or  even slightly decreasing and  then flat again recently, suggesting that increasing temperatures may not be entirely due to increasing carbon dioxide levels. 
  •  This is a graph of the change in worldwide temperatures over the last 130 years. Although the trend is decidedly upward, there are periods when temperatures are  flat or  even slightly decreasing and  then flat again recently, suggesting that increasing temperatures may not be entirely due to increasing carbon dioxide levels. 
  •  This is a graph of the change in worldwide temperatures over the last 130 years. Although the trend is decidedly upward, there are periods when temperatures are  flat or  even slightly decreasing and  then flat again recently, suggesting that increasing temperatures may not be entirely due to increasing carbon dioxide levels. 
  •  This is a graph of the change in worldwide temperatures over the last 130 years. Although the trend is decidedly upward, there are periods when temperatures are  flat or  even slightly decreasing and  then flat again recently, suggesting that increasing temperatures may not be entirely due to increasing carbon dioxide levels. 
  •  This is a graph of the change in worldwide temperatures over the last 130 years. Although the trend is decidedly upward, there are periods when temperatures are  flat or  even slightly decreasing and  then flat again recently, suggesting that increasing temperatures may not be entirely due to increasing carbon dioxide levels. 
  • The previous graph does not tell the entire story, since temperature changes have not occurred to the same extent during different seasons. For example, in Los Angeles,  temperatures have risen pretty dramatically over the last 130 years. However,  summer temperatures have not risen as quickly. In fact, summer temperatures  in the 1880’s were about the same as summer temperatures  in the 2000’s. In contrast,  winter temperatures have risen much more consistently and dramatically. Global warming models have predicted that warming will be greater during the winter than the summer. From a human perspective, one cannot say that higher temperatures during the winter are necessarily a bad thing. 
  • The previous graph does not tell the entire story, since temperature changes have not occurred to the same extent during different seasons. For example, in Los Angeles,  temperatures have risen pretty dramatically over the last 130 years. However,  summer temperatures have not risen as quickly. In fact, summer temperatures  in the 1880’s were about the same as summer temperatures  in the 2000’s. In contrast,  winter temperatures have risen much more consistently and dramatically. Global warming models have predicted that warming will be greater during the winter than the summer. From a human perspective, one cannot say that higher temperatures during the winter are necessarily a bad thing. 
  • The previous graph does not tell the entire story, since temperature changes have not occurred to the same extent during different seasons. For example, in Los Angeles,  temperatures have risen pretty dramatically over the last 130 years. However,  summer temperatures have not risen as quickly. In fact, summer temperatures  in the 1880’s were about the same as summer temperatures  in the 2000’s. In contrast,  winter temperatures have risen much more consistently and dramatically. Global warming models have predicted that warming will be greater during the winter than the summer. From a human perspective, one cannot say that higher temperatures during the winter are necessarily a bad thing. 
  • The previous graph does not tell the entire story, since temperature changes have not occurred to the same extent during different seasons. For example, in Los Angeles,  temperatures have risen pretty dramatically over the last 130 years. However,  summer temperatures have not risen as quickly. In fact, summer temperatures  in the 1880’s were about the same as summer temperatures  in the 2000’s. In contrast,  winter temperatures have risen much more consistently and dramatically. Global warming models have predicted that warming will be greater during the winter than the summer. From a human perspective, one cannot say that higher temperatures during the winter are necessarily a bad thing. 
  • The previous graph does not tell the entire story, since temperature changes have not occurred to the same extent during different seasons. For example, in Los Angeles,  temperatures have risen pretty dramatically over the last 130 years. However,  summer temperatures have not risen as quickly. In fact, summer temperatures  in the 1880’s were about the same as summer temperatures  in the 2000’s. In contrast,  winter temperatures have risen much more consistently and dramatically. Global warming models have predicted that warming will be greater during the winter than the summer. From a human perspective, one cannot say that higher temperatures during the winter are necessarily a bad thing. 
  • The previous graph does not tell the entire story, since temperature changes have not occurred to the same extent during different seasons. For example, in Los Angeles,  temperatures have risen pretty dramatically over the last 130 years. However,  summer temperatures have not risen as quickly. In fact, summer temperatures  in the 1880’s were about the same as summer temperatures  in the 2000’s. In contrast,  winter temperatures have risen much more consistently and dramatically. Global warming models have predicted that warming will be greater during the winter than the summer. From a human perspective, one cannot say that higher temperatures during the winter are necessarily a bad thing. 
  • The previous graph does not tell the entire story, since temperature changes have not occurred to the same extent during different seasons. For example, in Los Angeles,  temperatures have risen pretty dramatically over the last 130 years. However,  summer temperatures have not risen as quickly. In fact, summer temperatures  in the 1880’s were about the same as summer temperatures  in the 2000’s. In contrast,  winter temperatures have risen much more consistently and dramatically. Global warming models have predicted that warming will be greater during the winter than the summer. From a human perspective, one cannot say that higher temperatures during the winter are necessarily a bad thing. 
  • The previous graph does not tell the entire story, since temperature changes have not occurred to the same extent during different seasons. For example, in Los Angeles,  temperatures have risen pretty dramatically over the last 130 years. However,  summer temperatures have not risen as quickly. In fact, summer temperatures  in the 1880’s were about the same as summer temperatures  in the 2000’s. In contrast,  winter temperatures have risen much more consistently and dramatically. Global warming models have predicted that warming will be greater during the winter than the summer. From a human perspective, one cannot say that higher temperatures during the winter are necessarily a bad thing. 
  • The previous graph does not tell the entire story, since temperature changes have not occurred to the same extent during different seasons. For example, in Los Angeles,  temperatures have risen pretty dramatically over the last 130 years. However,  summer temperatures have not risen as quickly. In fact, summer temperatures  in the 1880’s were about the same as summer temperatures  in the 2000’s. In contrast,  winter temperatures have risen much more consistently and dramatically. Global warming models have predicted that warming will be greater during the winter than the summer. From a human perspective, one cannot say that higher temperatures during the winter are necessarily a bad thing. 
  • The previous graph does not tell the entire story, since temperature changes have not occurred to the same extent during different seasons. For example, in Los Angeles,  temperatures have risen pretty dramatically over the last 130 years. However,  summer temperatures have not risen as quickly. In fact, summer temperatures  in the 1880’s were about the same as summer temperatures  in the 2000’s. In contrast,  winter temperatures have risen much more consistently and dramatically. Global warming models have predicted that warming will be greater during the winter than the summer. From a human perspective, one cannot say that higher temperatures during the winter are necessarily a bad thing. 
  • The previous graph does not tell the entire story, since temperature changes have not occurred to the same extent during different seasons. For example, in Los Angeles,  temperatures have risen pretty dramatically over the last 130 years. However,  summer temperatures have not risen as quickly. In fact, summer temperatures  in the 1880’s were about the same as summer temperatures  in the 2000’s. In contrast,  winter temperatures have risen much more consistently and dramatically. Global warming models have predicted that warming will be greater during the winter than the summer. From a human perspective, one cannot say that higher temperatures during the winter are necessarily a bad thing. 
  • This is a map of global temperature changes for the year 2009 compared to a base period of 1951-1980. The colors in the reds and oranges represent temperature increases, whereas areas colored with blue represent temperature decreases. As can be seen here there are few areas of temperature decreases,  and nearly all of the dramatic temperature increases have occurred in the far northern latitudes. 
  • This is a map of global temperature changes for the year 2009 compared to a base period of 1951-1980. The colors in the reds and oranges represent temperature increases, whereas areas colored with blue represent temperature decreases. As can be seen here there are few areas of temperature decreases,  and nearly all of the dramatic temperature increases have occurred in the far northern latitudes. 
  • Now, we need to talk about proxies and how they are used in climate science.  Past temperatures changes beyond 120 years ago are approximated through what are called proxies. Common proxies include  tree rings,  ice cores,  pollen records,  plant macrofossils,  Sr/Ca isotope data, and  oxygen isotopes from stalactites and stalagmites. 
  • Now, we need to talk about proxies and how they are used in climate science.  Past temperatures changes beyond 120 years ago are approximated through what are called proxies. Common proxies include  tree rings,  ice cores,  pollen records,  plant macrofossils,  Sr/Ca isotope data, and  oxygen isotopes from stalactites and stalagmites. 
  • Now, we need to talk about proxies and how they are used in climate science.  Past temperatures changes beyond 120 years ago are approximated through what are called proxies. Common proxies include  tree rings,  ice cores,  pollen records,  plant macrofossils,  Sr/Ca isotope data, and  oxygen isotopes from stalactites and stalagmites. 
  • Now, we need to talk about proxies and how they are used in climate science.  Past temperatures changes beyond 120 years ago are approximated through what are called proxies. Common proxies include  tree rings,  ice cores,  pollen records,  plant macrofossils,  Sr/Ca isotope data, and  oxygen isotopes from stalactites and stalagmites. 
  • Now, we need to talk about proxies and how they are used in climate science.  Past temperatures changes beyond 120 years ago are approximated through what are called proxies. Common proxies include  tree rings,  ice cores,  pollen records,  plant macrofossils,  Sr/Ca isotope data, and  oxygen isotopes from stalactites and stalagmites. 
  • Now, we need to talk about proxies and how they are used in climate science.  Past temperatures changes beyond 120 years ago are approximated through what are called proxies. Common proxies include  tree rings,  ice cores,  pollen records,  plant macrofossils,  Sr/Ca isotope data, and  oxygen isotopes from stalactites and stalagmites. 
  • Now, we need to talk about proxies and how they are used in climate science.  Past temperatures changes beyond 120 years ago are approximated through what are called proxies. Common proxies include  tree rings,  ice cores,  pollen records,  plant macrofossils,  Sr/Ca isotope data, and  oxygen isotopes from stalactites and stalagmites. 
  • Now let’s examine the temperature history of the earth based upon these proxies.  Most recently, the earth was up to 1° C cooler than today, during what has been called the “Little Ice Age”. Preceding this period was the “Medieval warm period” during which time temperatures were up to 1° C warmer than today.  These periods of modest temperature changes occur at ~1,500 year intervals,  affecting mostly Northern Europe and the North Atlantic.  These temperature changes are largely the result of changes in what is called the thermohaline circulation.  In this model, cold water in the North Atlantic sinks and flows south through deep currents.  Warm water from the south flows north, moderating the climate of Europe and Eastern North America.  A dramatic shutdown of thermohaline circulation occurred 8,200 years ago as a large lake in Canada flooded the North Atlantic, resulting in much cooler temperatures in Europe. 
  • Now let’s examine the temperature history of the earth based upon these proxies.  Most recently, the earth was up to 1° C cooler than today, during what has been called the “Little Ice Age”. Preceding this period was the “Medieval warm period” during which time temperatures were up to 1° C warmer than today.  These periods of modest temperature changes occur at ~1,500 year intervals,  affecting mostly Northern Europe and the North Atlantic.  These temperature changes are largely the result of changes in what is called the thermohaline circulation.  In this model, cold water in the North Atlantic sinks and flows south through deep currents.  Warm water from the south flows north, moderating the climate of Europe and Eastern North America.  A dramatic shutdown of thermohaline circulation occurred 8,200 years ago as a large lake in Canada flooded the North Atlantic, resulting in much cooler temperatures in Europe. 
  • Now let’s examine the temperature history of the earth based upon these proxies.  Most recently, the earth was up to 1° C cooler than today, during what has been called the “Little Ice Age”. Preceding this period was the “Medieval warm period” during which time temperatures were up to 1° C warmer than today.  These periods of modest temperature changes occur at ~1,500 year intervals,  affecting mostly Northern Europe and the North Atlantic.  These temperature changes are largely the result of changes in what is called the thermohaline circulation.  In this model, cold water in the North Atlantic sinks and flows south through deep currents.  Warm water from the south flows north, moderating the climate of Europe and Eastern North America.  A dramatic shutdown of thermohaline circulation occurred 8,200 years ago as a large lake in Canada flooded the North Atlantic, resulting in much cooler temperatures in Europe. 
  • Now let’s examine the temperature history of the earth based upon these proxies.  Most recently, the earth was up to 1° C cooler than today, during what has been called the “Little Ice Age”. Preceding this period was the “Medieval warm period” during which time temperatures were up to 1° C warmer than today.  These periods of modest temperature changes occur at ~1,500 year intervals,  affecting mostly Northern Europe and the North Atlantic.  These temperature changes are largely the result of changes in what is called the thermohaline circulation.  In this model, cold water in the North Atlantic sinks and flows south through deep currents.  Warm water from the south flows north, moderating the climate of Europe and Eastern North America.  A dramatic shutdown of thermohaline circulation occurred 8,200 years ago as a large lake in Canada flooded the North Atlantic, resulting in much cooler temperatures in Europe. 
  • Now let’s examine the temperature history of the earth based upon these proxies.  Most recently, the earth was up to 1° C cooler than today, during what has been called the “Little Ice Age”. Preceding this period was the “Medieval warm period” during which time temperatures were up to 1° C warmer than today.  These periods of modest temperature changes occur at ~1,500 year intervals,  affecting mostly Northern Europe and the North Atlantic.  These temperature changes are largely the result of changes in what is called the thermohaline circulation.  In this model, cold water in the North Atlantic sinks and flows south through deep currents.  Warm water from the south flows north, moderating the climate of Europe and Eastern North America.  A dramatic shutdown of thermohaline circulation occurred 8,200 years ago as a large lake in Canada flooded the North Atlantic, resulting in much cooler temperatures in Europe. 
  • Now let’s examine the temperature history of the earth based upon these proxies.  Most recently, the earth was up to 1° C cooler than today, during what has been called the “Little Ice Age”. Preceding this period was the “Medieval warm period” during which time temperatures were up to 1° C warmer than today.  These periods of modest temperature changes occur at ~1,500 year intervals,  affecting mostly Northern Europe and the North Atlantic.  These temperature changes are largely the result of changes in what is called the thermohaline circulation.  In this model, cold water in the North Atlantic sinks and flows south through deep currents.  Warm water from the south flows north, moderating the climate of Europe and Eastern North America.  A dramatic shutdown of thermohaline circulation occurred 8,200 years ago as a large lake in Canada flooded the North Atlantic, resulting in much cooler temperatures in Europe. 
  • Now let’s examine the temperature history of the earth based upon these proxies.  Most recently, the earth was up to 1° C cooler than today, during what has been called the “Little Ice Age”. Preceding this period was the “Medieval warm period” during which time temperatures were up to 1° C warmer than today.  These periods of modest temperature changes occur at ~1,500 year intervals,  affecting mostly Northern Europe and the North Atlantic.  These temperature changes are largely the result of changes in what is called the thermohaline circulation.  In this model, cold water in the North Atlantic sinks and flows south through deep currents.  Warm water from the south flows north, moderating the climate of Europe and Eastern North America.  A dramatic shutdown of thermohaline circulation occurred 8,200 years ago as a large lake in Canada flooded the North Atlantic, resulting in much cooler temperatures in Europe. 
  • Now let’s examine the temperature history of the earth based upon these proxies.  Most recently, the earth was up to 1° C cooler than today, during what has been called the “Little Ice Age”. Preceding this period was the “Medieval warm period” during which time temperatures were up to 1° C warmer than today.  These periods of modest temperature changes occur at ~1,500 year intervals,  affecting mostly Northern Europe and the North Atlantic.  These temperature changes are largely the result of changes in what is called the thermohaline circulation.  In this model, cold water in the North Atlantic sinks and flows south through deep currents.  Warm water from the south flows north, moderating the climate of Europe and Eastern North America.  A dramatic shutdown of thermohaline circulation occurred 8,200 years ago as a large lake in Canada flooded the North Atlantic, resulting in much cooler temperatures in Europe. 
  • Now let’s examine the temperature history of the earth based upon these proxies.  Most recently, the earth was up to 1° C cooler than today, during what has been called the “Little Ice Age”. Preceding this period was the “Medieval warm period” during which time temperatures were up to 1° C warmer than today.  These periods of modest temperature changes occur at ~1,500 year intervals,  affecting mostly Northern Europe and the North Atlantic.  These temperature changes are largely the result of changes in what is called the thermohaline circulation.  In this model, cold water in the North Atlantic sinks and flows south through deep currents.  Warm water from the south flows north, moderating the climate of Europe and Eastern North America.  A dramatic shutdown of thermohaline circulation occurred 8,200 years ago as a large lake in Canada flooded the North Atlantic, resulting in much cooler temperatures in Europe. 
  • Now let’s examine the temperature history of the earth based upon these proxies.  Most recently, the earth was up to 1° C cooler than today, during what has been called the “Little Ice Age”. Preceding this period was the “Medieval warm period” during which time temperatures were up to 1° C warmer than today.  These periods of modest temperature changes occur at ~1,500 year intervals,  affecting mostly Northern Europe and the North Atlantic.  These temperature changes are largely the result of changes in what is called the thermohaline circulation.  In this model, cold water in the North Atlantic sinks and flows south through deep currents.  Warm water from the south flows north, moderating the climate of Europe and Eastern North America.  A dramatic shutdown of thermohaline circulation occurred 8,200 years ago as a large lake in Canada flooded the North Atlantic, resulting in much cooler temperatures in Europe. 
  • Now let’s examine the temperature history of the earth based upon these proxies.  Most recently, the earth was up to 1° C cooler than today, during what has been called the “Little Ice Age”. Preceding this period was the “Medieval warm period” during which time temperatures were up to 1° C warmer than today.  These periods of modest temperature changes occur at ~1,500 year intervals,  affecting mostly Northern Europe and the North Atlantic.  These temperature changes are largely the result of changes in what is called the thermohaline circulation.  In this model, cold water in the North Atlantic sinks and flows south through deep currents.  Warm water from the south flows north, moderating the climate of Europe and Eastern North America.  A dramatic shutdown of thermohaline circulation occurred 8,200 years ago as a large lake in Canada flooded the North Atlantic, resulting in much cooler temperatures in Europe. 
  • Now let’s examine the temperature history of the earth based upon these proxies.  Most recently, the earth was up to 1° C cooler than today, during what has been called the “Little Ice Age”. Preceding this period was the “Medieval warm period” during which time temperatures were up to 1° C warmer than today.  These periods of modest temperature changes occur at ~1,500 year intervals,  affecting mostly Northern Europe and the North Atlantic.  These temperature changes are largely the result of changes in what is called the thermohaline circulation.  In this model, cold water in the North Atlantic sinks and flows south through deep currents.  Warm water from the south flows north, moderating the climate of Europe and Eastern North America.  A dramatic shutdown of thermohaline circulation occurred 8,200 years ago as a large lake in Canada flooded the North Atlantic, resulting in much cooler temperatures in Europe. 
  • Now let’s examine the temperature history of the earth based upon these proxies.  Most recently, the earth was up to 1° C cooler than today, during what has been called the “Little Ice Age”. Preceding this period was the “Medieval warm period” during which time temperatures were up to 1° C warmer than today.  These periods of modest temperature changes occur at ~1,500 year intervals,  affecting mostly Northern Europe and the North Atlantic.  These temperature changes are largely the result of changes in what is called the thermohaline circulation.  In this model, cold water in the North Atlantic sinks and flows south through deep currents.  Warm water from the south flows north, moderating the climate of Europe and Eastern North America.  A dramatic shutdown of thermohaline circulation occurred 8,200 years ago as a large lake in Canada flooded the North Atlantic, resulting in much cooler temperatures in Europe. 
  • Now let’s examine the temperature history of the earth based upon these proxies.  Most recently, the earth was up to 1° C cooler than today, during what has been called the “Little Ice Age”. Preceding this period was the “Medieval warm period” during which time temperatures were up to 1° C warmer than today.  These periods of modest temperature changes occur at ~1,500 year intervals,  affecting mostly Northern Europe and the North Atlantic.  These temperature changes are largely the result of changes in what is called the thermohaline circulation.  In this model, cold water in the North Atlantic sinks and flows south through deep currents.  Warm water from the south flows north, moderating the climate of Europe and Eastern North America.  A dramatic shutdown of thermohaline circulation occurred 8,200 years ago as a large lake in Canada flooded the North Atlantic, resulting in much cooler temperatures in Europe. 
  • Now let’s examine the temperature history of the earth based upon these proxies.  Most recently, the earth was up to 1° C cooler than today, during what has been called the “Little Ice Age”. Preceding this period was the “Medieval warm period” during which time temperatures were up to 1° C warmer than today.  These periods of modest temperature changes occur at ~1,500 year intervals,  affecting mostly Northern Europe and the North Atlantic.  These temperature changes are largely the result of changes in what is called the thermohaline circulation.  In this model, cold water in the North Atlantic sinks and flows south through deep currents.  Warm water from the south flows north, moderating the climate of Europe and Eastern North America.  A dramatic shutdown of thermohaline circulation occurred 8,200 years ago as a large lake in Canada flooded the North Atlantic, resulting in much cooler temperatures in Europe. 
  • Now let’s examine the temperature history of the earth based upon these proxies.  Most recently, the earth was up to 1° C cooler than today, during what has been called the “Little Ice Age”. Preceding this period was the “Medieval warm period” during which time temperatures were up to 1° C warmer than today.  These periods of modest temperature changes occur at ~1,500 year intervals,  affecting mostly Northern Europe and the North Atlantic.  These temperature changes are largely the result of changes in what is called the thermohaline circulation.  In this model, cold water in the North Atlantic sinks and flows south through deep currents.  Warm water from the south flows north, moderating the climate of Europe and Eastern North America.  A dramatic shutdown of thermohaline circulation occurred 8,200 years ago as a large lake in Canada flooded the North Atlantic, resulting in much cooler temperatures in Europe. 
  • Now let’s examine the temperature history of the earth based upon these proxies.  Most recently, the earth was up to 1° C cooler than today, during what has been called the “Little Ice Age”. Preceding this period was the “Medieval warm period” during which time temperatures were up to 1° C warmer than today.  These periods of modest temperature changes occur at ~1,500 year intervals,  affecting mostly Northern Europe and the North Atlantic.  These temperature changes are largely the result of changes in what is called the thermohaline circulation.  In this model, cold water in the North Atlantic sinks and flows south through deep currents.  Warm water from the south flows north, moderating the climate of Europe and Eastern North America.  A dramatic shutdown of thermohaline circulation occurred 8,200 years ago as a large lake in Canada flooded the North Atlantic, resulting in much cooler temperatures in Europe. 
  • Now let’s examine the temperature history of the earth based upon these proxies.  Most recently, the earth was up to 1° C cooler than today, during what has been called the “Little Ice Age”. Preceding this period was the “Medieval warm period” during which time temperatures were up to 1° C warmer than today.  These periods of modest temperature changes occur at ~1,500 year intervals,  affecting mostly Northern Europe and the North Atlantic.  These temperature changes are largely the result of changes in what is called the thermohaline circulation.  In this model, cold water in the North Atlantic sinks and flows south through deep currents.  Warm water from the south flows north, moderating the climate of Europe and Eastern North America.  A dramatic shutdown of thermohaline circulation occurred 8,200 years ago as a large lake in Canada flooded the North Atlantic, resulting in much cooler temperatures in Europe. 
  • Now let’s examine the temperature history of the earth based upon these proxies.  Most recently, the earth was up to 1° C cooler than today, during what has been called the “Little Ice Age”. Preceding this period was the “Medieval warm period” during which time temperatures were up to 1° C warmer than today.  These periods of modest temperature changes occur at ~1,500 year intervals,  affecting mostly Northern Europe and the North Atlantic.  These temperature changes are largely the result of changes in what is called the thermohaline circulation.  In this model, cold water in the North Atlantic sinks and flows south through deep currents.  Warm water from the south flows north, moderating the climate of Europe and Eastern North America.  A dramatic shutdown of thermohaline circulation occurred 8,200 years ago as a large lake in Canada flooded the North Atlantic, resulting in much cooler temperatures in Europe. 
  • Now let’s examine the temperature history of the earth based upon these proxies.  Most recently, the earth was up to 1° C cooler than today, during what has been called the “Little Ice Age”. Preceding this period was the “Medieval warm period” during which time temperatures were up to 1° C warmer than today.  These periods of modest temperature changes occur at ~1,500 year intervals,  affecting mostly Northern Europe and the North Atlantic.  These temperature changes are largely the result of changes in what is called the thermohaline circulation.  In this model, cold water in the North Atlantic sinks and flows south through deep currents.  Warm water from the south flows north, moderating the climate of Europe and Eastern North America.  A dramatic shutdown of thermohaline circulation occurred 8,200 years ago as a large lake in Canada flooded the North Atlantic, resulting in much cooler temperatures in Europe. 
  • Now let’s examine the temperature history of the earth based upon these proxies.  Most recently, the earth was up to 1° C cooler than today, during what has been called the “Little Ice Age”. Preceding this period was the “Medieval warm period” during which time temperatures were up to 1° C warmer than today.  These periods of modest temperature changes occur at ~1,500 year intervals,  affecting mostly Northern Europe and the North Atlantic.  These temperature changes are largely the result of changes in what is called the thermohaline circulation.  In this model, cold water in the North Atlantic sinks and flows south through deep currents.  Warm water from the south flows north, moderating the climate of Europe and Eastern North America.  A dramatic shutdown of thermohaline circulation occurred 8,200 years ago as a large lake in Canada flooded the North Atlantic, resulting in much cooler temperatures in Europe. 
  • Now let’s examine the temperature history of the earth based upon these proxies.  Most recently, the earth was up to 1° C cooler than today, during what has been called the “Little Ice Age”. Preceding this period was the “Medieval warm period” during which time temperatures were up to 1° C warmer than today.  These periods of modest temperature changes occur at ~1,500 year intervals,  affecting mostly Northern Europe and the North Atlantic.  These temperature changes are largely the result of changes in what is called the thermohaline circulation.  In this model, cold water in the North Atlantic sinks and flows south through deep currents.  Warm water from the south flows north, moderating the climate of Europe and Eastern North America.  A dramatic shutdown of thermohaline circulation occurred 8,200 years ago as a large lake in Canada flooded the North Atlantic, resulting in much cooler temperatures in Europe. 
  • Now let’s examine the temperature history of the earth based upon these proxies.  Most recently, the earth was up to 1° C cooler than today, during what has been called the “Little Ice Age”. Preceding this period was the “Medieval warm period” during which time temperatures were up to 1° C warmer than today.  These periods of modest temperature changes occur at ~1,500 year intervals,  affecting mostly Northern Europe and the North Atlantic.  These temperature changes are largely the result of changes in what is called the thermohaline circulation.  In this model, cold water in the North Atlantic sinks and flows south through deep currents.  Warm water from the south flows north, moderating the climate of Europe and Eastern North America.  A dramatic shutdown of thermohaline circulation occurred 8,200 years ago as a large lake in Canada flooded the North Atlantic, resulting in much cooler temperatures in Europe. 
  • Now let’s examine the temperature history of the earth based upon these proxies.  Most recently, the earth was up to 1° C cooler than today, during what has been called the “Little Ice Age”. Preceding this period was the “Medieval warm period” during which time temperatures were up to 1° C warmer than today.  These periods of modest temperature changes occur at ~1,500 year intervals,  affecting mostly Northern Europe and the North Atlantic.  These temperature changes are largely the result of changes in what is called the thermohaline circulation.  In this model, cold water in the North Atlantic sinks and flows south through deep currents.  Warm water from the south flows north, moderating the climate of Europe and Eastern North America.  A dramatic shutdown of thermohaline circulation occurred 8,200 years ago as a large lake in Canada flooded the North Atlantic, resulting in much cooler temperatures in Europe. 
  • Now let’s examine the temperature history of the earth based upon these proxies.  Most recently, the earth was up to 1° C cooler than today, during what has been called the “Little Ice Age”. Preceding this period was the “Medieval warm period” during which time temperatures were up to 1° C warmer than today.  These periods of modest temperature changes occur at ~1,500 year intervals,  affecting mostly Northern Europe and the North Atlantic.  These temperature changes are largely the result of changes in what is called the thermohaline circulation.  In this model, cold water in the North Atlantic sinks and flows south through deep currents.  Warm water from the south flows north, moderating the climate of Europe and Eastern North America.  A dramatic shutdown of thermohaline circulation occurred 8,200 years ago as a large lake in Canada flooded the North Atlantic, resulting in much cooler temperatures in Europe. 
  • Now let’s examine the temperature history of the earth based upon these proxies.  Most recently, the earth was up to 1° C cooler than today, during what has been called the “Little Ice Age”. Preceding this period was the “Medieval warm period” during which time temperatures were up to 1° C warmer than today.  These periods of modest temperature changes occur at ~1,500 year intervals,  affecting mostly Northern Europe and the North Atlantic.  These temperature changes are largely the result of changes in what is called the thermohaline circulation.  In this model, cold water in the North Atlantic sinks and flows south through deep currents.  Warm water from the south flows north, moderating the climate of Europe and Eastern North America.  A dramatic shutdown of thermohaline circulation occurred 8,200 years ago as a large lake in Canada flooded the North Atlantic, resulting in much cooler temperatures in Europe. 
  • In fact, ocean currents are extremely important in determining the climate of the world’s continents.  This model shows the major ocean currents, with orange representing warm surface currents and blue representing cold deep currents.  The light circles represent areas where heat is release into the atmosphere. 
  • In fact, ocean currents are extremely important in determining the climate of the world’s continents.  This model shows the major ocean currents, with orange representing warm surface currents and blue representing cold deep currents.  The light circles represent areas where heat is release into the atmosphere. 
  • In fact, ocean currents are extremely important in determining the climate of the world’s continents.  This model shows the major ocean currents, with orange representing warm surface currents and blue representing cold deep currents.  The light circles represent areas where heat is release into the atmosphere. 
  • In fact, ocean currents are extremely important in determining the climate of the world’s continents.  This model shows the major ocean currents, with orange representing warm surface currents and blue representing cold deep currents.  The light circles represent areas where heat is release into the atmosphere. 
  • In fact, ocean currents are extremely important in determining the climate of the world’s continents.  This model shows the major ocean currents, with orange representing warm surface currents and blue representing cold deep currents.  The light circles represent areas where heat is release into the atmosphere. 
  • In fact, ocean currents are extremely important in determining the climate of the world’s continents.  This model shows the major ocean currents, with orange representing warm surface currents and blue representing cold deep currents.  The light circles represent areas where heat is release into the atmosphere. 
  • In fact, ocean currents are extremely important in determining the climate of the world’s continents.  This model shows the major ocean currents, with orange representing warm surface currents and blue representing cold deep currents.  The light circles represent areas where heat is release into the atmosphere. 
  • In fact, ocean currents are extremely important in determining the climate of the world’s continents.  This model shows the major ocean currents, with orange representing warm surface currents and blue representing cold deep currents.  The light circles represent areas where heat is release into the atmosphere. 
  • In fact, ocean currents are extremely important in determining the climate of the world’s continents.  This model shows the major ocean currents, with orange representing warm surface currents and blue representing cold deep currents.  The light circles represent areas where heat is release into the atmosphere. 
  • In fact, ocean currents are extremely important in determining the climate of the world’s continents.  This model shows the major ocean currents, with orange representing warm surface currents and blue representing cold deep currents.  The light circles represent areas where heat is release into the atmosphere. 
  • In fact, ocean currents are extremely important in determining the climate of the world’s continents.  This model shows the major ocean currents, with orange representing warm surface currents and blue representing cold deep currents.  The light circles represent areas where heat is release into the atmosphere. 
  • In fact, ocean currents are extremely important in determining the climate of the world’s continents.  This model shows the major ocean currents, with orange representing warm surface currents and blue representing cold deep currents.  The light circles represent areas where heat is release into the atmosphere. 
  • In fact, ocean currents are extremely important in determining the climate of the world’s continents.  This model shows the major ocean currents, with orange representing warm surface currents and blue representing cold deep currents.  The light circles represent areas where heat is release into the atmosphere. 
  • In fact, ocean currents are extremely important in determining the climate of the world’s continents.  This model shows the major ocean currents, with orange representing warm surface currents and blue representing cold deep currents.  The light circles represent areas where heat is release into the atmosphere. 
  • In fact, ocean currents are extremely important in determining the climate of the world’s continents.  This model shows the major ocean currents, with orange representing warm surface currents and blue representing cold deep currents.  The light circles represent areas where heat is release into the atmosphere. 
  • In fact, ocean currents are extremely important in determining the climate of the world’s continents.  This model shows the major ocean currents, with orange representing warm surface currents and blue representing cold deep currents.  The light circles represent areas where heat is release into the atmosphere. 
  • In fact, ocean currents are extremely important in determining the climate of the world’s continents.  This model shows the major ocean currents, with orange representing warm surface currents and blue representing cold deep currents.  The light circles represent areas where heat is release into the atmosphere. 
  • In fact, ocean currents are extremely important in determining the climate of the world’s continents.  This model shows the major ocean currents, with orange representing warm surface currents and blue representing cold deep currents.  The light circles represent areas where heat is release into the atmosphere. 
  • In fact, ocean currents are extremely important in determining the climate of the world’s continents.  This model shows the major ocean currents, with orange representing warm surface currents and blue representing cold deep currents.  The light circles represent areas where heat is release into the atmosphere. 
  • In fact, ocean currents are extremely important in determining the climate of the world’s continents.  This model shows the major ocean currents, with orange representing warm surface currents and blue representing cold deep currents.  The light circles represent areas where heat is release into the atmosphere. 
  • In fact, ocean currents are extremely important in determining the climate of the world’s continents.  This model shows the major ocean currents, with orange representing warm surface currents and blue representing cold deep currents.  The light circles represent areas where heat is release into the atmosphere. 
  • In fact, ocean currents are extremely important in determining the climate of the world’s continents.  This model shows the major ocean currents, with orange representing warm surface currents and blue representing cold deep currents.  The light circles represent areas where heat is release into the atmosphere. 
  • In fact, ocean currents are extremely important in determining the climate of the world’s continents.  This model shows the major ocean currents, with orange representing warm surface currents and blue representing cold deep currents.  The light circles represent areas where heat is release into the atmosphere. 
  • In fact, ocean currents are extremely important in determining the climate of the world’s continents.  This model shows the major ocean currents, with orange representing warm surface currents and blue representing cold deep currents.  The light circles represent areas where heat is release into the atmosphere. 
  • In fact, ocean currents are extremely important in determining the climate of the world’s continents.  This model shows the major ocean currents, with orange representing warm surface currents and blue representing cold deep currents.  The light circles represent areas where heat is release into the atmosphere. 
  • In fact, ocean currents are extremely important in determining the climate of the world’s continents.  This model shows the major ocean currents, with orange representing warm surface currents and blue representing cold deep currents.  The light circles represent areas where heat is release into the atmosphere. 
  • In fact, ocean currents are extremely important in determining the climate of the world’s continents.  This model shows the major ocean currents, with orange representing warm surface currents and blue representing cold deep currents.  The light circles represent areas where heat is release into the atmosphere. 
  • In fact, ocean currents are extremely important in determining the climate of the world’s continents.  This model shows the major ocean currents, with orange representing warm surface currents and blue representing cold deep currents.  The light circles represent areas where heat is release into the atmosphere. 
  • In fact, ocean currents are extremely important in determining the climate of the world’s continents.  This model shows the major ocean currents, with orange representing warm surface currents and blue representing cold deep currents.  The light circles represent areas where heat is release into the atmosphere. 
  • In fact, ocean currents are extremely important in determining the climate of the world’s continents.  This model shows the major ocean currents, with orange representing warm surface currents and blue representing cold deep currents.  The light circles represent areas where heat is release into the atmosphere. 
  • In fact, ocean currents are extremely important in determining the climate of the world’s continents.  This model shows the major ocean currents, with orange representing warm surface currents and blue representing cold deep currents.  The light circles represent areas where heat is release into the atmosphere. 
  • In fact, ocean currents are extremely important in determining the climate of the world’s continents.  This model shows the major ocean currents, with orange representing warm surface currents and blue representing cold deep currents.  The light circles represent areas where heat is release into the atmosphere. 
  • In fact, ocean currents are extremely important in determining the climate of the world’s continents.  This model shows the major ocean currents, with orange representing warm surface currents and blue representing cold deep currents.  The light circles represent areas where heat is release into the atmosphere. 
  • In fact, ocean currents are extremely important in determining the climate of the world’s continents.  This model shows the major ocean currents, with orange representing warm surface currents and blue representing cold deep currents.  The light circles represent areas where heat is release into the atmosphere. 
  • In fact, ocean currents are extremely important in determining the climate of the world’s continents.  This model shows the major ocean currents, with orange representing warm surface currents and blue representing cold deep currents.  The light circles represent areas where heat is release into the atmosphere. 
  • In fact, ocean currents are extremely important in determining the climate of the world’s continents.  This model shows the major ocean currents, with orange representing warm surface currents and blue representing cold deep currents.  The light circles represent areas where heat is release into the atmosphere. 
  • In fact, ocean currents are extremely important in determining the climate of the world’s continents.  This model shows the major ocean currents, with orange representing warm surface currents and blue representing cold deep currents.  The light circles represent areas where heat is release into the atmosphere. 
  • In fact, ocean currents are extremely important in determining the climate of the world’s continents.  This model shows the major ocean currents, with orange representing warm surface currents and blue representing cold deep currents.  The light circles represent areas where heat is release into the atmosphere. 
  • In fact, ocean currents are extremely important in determining the climate of the world’s continents.  This model shows the major ocean currents, with orange representing warm surface currents and blue representing cold deep currents.  The light circles represent areas where heat is release into the atmosphere. 
  • 
    For the past 3 million years, the earth has been experiencing ~100,000 year long cycles of glaciation followed by ~10,000 year long interglacial periods 
    These climate periods are largely the result of cycles in the earth’s orbit – precession, obliquity, and eccentricity 
  • 
    For the past 3 million years, the earth has been experiencing ~100,000 year long cycles of glaciation followed by ~10,000 year long interglacial periods 
    These climate periods are largely the result of cycles in the earth’s orbit – precession, obliquity, and eccentricity 
  •  Precession is the wobble of the earth’s tilt in relation to the seasons.  Right now, the earth is farthest to the Sun during northern hemisphere’s summer and nearest during northern hemisphere’s winter. However, in another 20,000 years, the earth will be reversed with the  earth closest to the Sun during northern hemisphere’s summer and farthest during northern hemisphere’s winter. 
  •  Precession is the wobble of the earth’s tilt in relation to the seasons.  Right now, the earth is farthest to the Sun during northern hemisphere’s summer and nearest during northern hemisphere’s winter. However, in another 20,000 years, the earth will be reversed with the  earth closest to the Sun during northern hemisphere’s summer and farthest during northern hemisphere’s winter. 
  •  Precession is the wobble of the earth’s tilt in relation to the seasons.  Right now, the earth is farthest to the Sun during northern hemisphere’s summer and nearest during northern hemisphere’s winter. However, in another 20,000 years, the earth will be reversed with the  earth closest to the Sun during northern hemisphere’s summer and farthest during northern hemisphere’s winter. 
  •  Precession is the wobble of the earth’s tilt in relation to the seasons.  Right now, the earth is farthest to the Sun during northern hemisphere’s summer and nearest during northern hemisphere’s winter. However, in another 20,000 years, the earth will be reversed with the  earth closest to the Sun during northern hemisphere’s summer and farthest during northern hemisphere’s winter. 
  •  Precession is the wobble of the earth’s tilt in relation to the seasons.  Right now, the earth is farthest to the Sun during northern hemisphere’s summer and nearest during northern hemisphere’s winter. However, in another 20,000 years, the earth will be reversed with the  earth closest to the Sun during northern hemisphere’s summer and farthest during northern hemisphere’s winter. 
  •  Precession is the wobble of the earth’s tilt in relation to the seasons.  Right now, the earth is farthest to the Sun during northern hemisphere’s summer and nearest during northern hemisphere’s winter. However, in another 20,000 years, the earth will be reversed with the  earth closest to the Sun during northern hemisphere’s summer and farthest during northern hemisphere’s winter. 
  •  Precession is the wobble of the earth’s tilt in relation to the seasons.  Right now, the earth is farthest to the Sun during northern hemisphere’s summer and nearest during northern hemisphere’s winter. However, in another 20,000 years, the earth will be reversed with the  earth closest to the Sun during northern hemisphere’s summer and farthest during northern hemisphere’s winter. 
  •  Precession is the wobble of the earth’s tilt in relation to the seasons.  Right now, the earth is farthest to the Sun during northern hemisphere’s summer and nearest during northern hemisphere’s winter. However, in another 20,000 years, the earth will be reversed with the  earth closest to the Sun during northern hemisphere’s summer and farthest during northern hemisphere’s winter. 
  •  Precession is the wobble of the earth’s tilt in relation to the seasons.  Right now, the earth is farthest to the Sun during northern hemisphere’s summer and nearest during northern hemisphere’s winter. However, in another 20,000 years, the earth will be reversed with the  earth closest to the Sun during northern hemisphere’s summer and farthest during northern hemisphere’s winter. 
  •  Precession is the wobble of the earth’s tilt in relation to the seasons.  Right now, the earth is farthest to the Sun during northern hemisphere’s summer and nearest during northern hemisphere’s winter. However, in another 20,000 years, the earth will be reversed with the  earth closest to the Sun during northern hemisphere’s summer and farthest during northern hemisphere’s winter. 
  •  Precession is the wobble of the earth’s tilt in relation to the seasons.  Right now, the earth is farthest to the Sun during northern hemisphere’s summer and nearest during northern hemisphere’s winter. However, in another 20,000 years, the earth will be reversed with the  earth closest to the Sun during northern hemisphere’s summer and farthest during northern hemisphere’s winter. 
  •  Precession is the wobble of the earth’s tilt in relation to the seasons.  Right now, the earth is farthest to the Sun during northern hemisphere’s summer and nearest during northern hemisphere’s winter. However, in another 20,000 years, the earth will be reversed with the  earth closest to the Sun during northern hemisphere’s summer and farthest during northern hemisphere’s winter. 
  •  Precession is the wobble of the earth’s tilt in relation to the seasons.  Right now, the earth is farthest to the Sun during northern hemisphere’s summer and nearest during northern hemisphere’s winter. However, in another 20,000 years, the earth will be reversed with the  earth closest to the Sun during northern hemisphere’s summer and farthest during northern hemisphere’s winter. 
  •  Precession is the wobble of the earth’s tilt in relation to the seasons.  Right now, the earth is farthest to the Sun during northern hemisphere’s summer and nearest during northern hemisphere’s winter. However, in another 20,000 years, the earth will be reversed with the  earth closest to the Sun during northern hemisphere’s summer and farthest during northern hemisphere’s winter. 
  •  Precession is the wobble of the earth’s tilt in relation to the seasons.  Right now, the earth is farthest to the Sun during northern hemisphere’s summer and nearest during northern hemisphere’s winter. However, in another 20,000 years, the earth will be reversed with the  earth closest to the Sun during northern hemisphere’s summer and farthest during northern hemisphere’s winter. 
  •  Precession is the wobble of the earth’s tilt in relation to the seasons.  Right now, the earth is farthest to the Sun during northern hemisphere’s summer and nearest during northern hemisphere’s winter. However, in another 20,000 years, the earth will be reversed with the  earth closest to the Sun during northern hemisphere’s summer and farthest during northern hemisphere’s winter. 
  •  Precession is the wobble of the earth’s tilt in relation to the seasons.  Right now, the earth is farthest to the Sun during northern hemisphere’s summer and nearest during northern hemisphere’s winter. However, in another 20,000 years, the earth will be reversed with the  earth closest to the Sun during northern hemisphere’s summer and farthest during northern hemisphere’s winter. 
  •  Precession is the wobble of the earth’s tilt in relation to the seasons.  Right now, the earth is farthest to the Sun during northern hemisphere’s summer and nearest during northern hemisphere’s winter. However, in another 20,000 years, the earth will be reversed with the  earth closest to the Sun during northern hemisphere’s summer and farthest during northern hemisphere’s winter. 
  •  Precession is the wobble of the earth’s tilt in relation to the seasons.  Right now, the earth is farthest to the Sun during northern hemisphere’s summer and nearest during northern hemisphere’s winter. However, in another 20,000 years, the earth will be reversed with the  earth closest to the Sun during northern hemisphere’s summer and farthest during northern hemisphere’s winter. 
  •  Precession is the wobble of the earth’s tilt in relation to the seasons.  Right now, the earth is farthest to the Sun during northern hemisphere’s summer and nearest during northern hemisphere’s winter. However, in another 20,000 years, the earth will be reversed with the  earth closest to the Sun during northern hemisphere’s summer and farthest during northern hemisphere’s winter. 
  •  Precession is the wobble of the earth’s tilt in relation to the seasons.  Right now, the earth is farthest to the Sun during northern hemisphere’s summer and nearest during northern hemisphere’s winter. However, in another 20,000 years, the earth will be reversed with the  earth closest to the Sun during northern hemisphere’s summer and farthest during northern hemisphere’s winter. 
  •  Precession is the wobble of the earth’s tilt in relation to the seasons.  Right now, the earth is farthest to the Sun during northern hemisphere’s summer and nearest during northern hemisphere’s winter. However, in another 20,000 years, the earth will be reversed with the  earth closest to the Sun during northern hemisphere’s summer and farthest during northern hemisphere’s winter. 
  •  Precession is the wobble of the earth’s tilt in relation to the seasons.  Right now, the earth is farthest to the Sun during northern hemisphere’s summer and nearest during northern hemisphere’s winter. However, in another 20,000 years, the earth will be reversed with the  earth closest to the Sun during northern hemisphere’s summer and farthest during northern hemisphere’s winter. 
  •  Precession is the wobble of the earth’s tilt in relation to the seasons.  Right now, the earth is farthest to the Sun during northern hemisphere’s summer and nearest during northern hemisphere’s winter. However, in another 20,000 years, the earth will be reversed with the  earth closest to the Sun during northern hemisphere’s summer and farthest during northern hemisphere’s winter. 
  •  Precession is the wobble of the earth’s tilt in relation to the seasons.  Right now, the earth is farthest to the Sun during northern hemisphere’s summer and nearest during northern hemisphere’s winter. However, in another 20,000 years, the earth will be reversed with the  earth closest to the Sun during northern hemisphere’s summer and farthest during northern hemisphere’s winter. 
  •  Precession is the wobble of the earth’s tilt in relation to the seasons.  Right now, the earth is farthest to the Sun during northern hemisphere’s summer and nearest during northern hemisphere’s winter. However, in another 20,000 years, the earth will be reversed with the  earth closest to the Sun during northern hemisphere’s summer and farthest during northern hemisphere’s winter. 
  •  Precession is the wobble of the earth’s tilt in relation to the seasons.  Right now, the earth is farthest to the Sun during northern hemisphere’s summer and nearest during northern hemisphere’s winter. However, in another 20,000 years, the earth will be reversed with the  earth closest to the Sun during northern hemisphere’s summer and farthest during northern hemisphere’s winter. 
  •  Precession is the wobble of the earth’s tilt in relation to the seasons.  Right now, the earth is farthest to the Sun during northern hemisphere’s summer and nearest during northern hemisphere’s winter. However, in another 20,000 years, the earth will be reversed with the  earth closest to the Sun during northern hemisphere’s summer and farthest during northern hemisphere’s winter. 
  •  Precession is the wobble of the earth’s tilt in relation to the seasons.  Right now, the earth is farthest to the Sun during northern hemisphere’s summer and nearest during northern hemisphere’s winter. However, in another 20,000 years, the earth will be reversed with the  earth closest to the Sun during northern hemisphere’s summer and farthest during northern hemisphere’s winter. 
  •  Precession is the wobble of the earth’s tilt in relation to the seasons.  Right now, the earth is farthest to the Sun during northern hemisphere’s summer and nearest during northern hemisphere’s winter. However, in another 20,000 years, the earth will be reversed with the  earth closest to the Sun during northern hemisphere’s summer and farthest during northern hemisphere’s winter. 
  •  Precession is the wobble of the earth’s tilt in relation to the seasons.  Right now, the earth is farthest to the Sun during northern hemisphere’s summer and nearest during northern hemisphere’s winter. However, in another 20,000 years, the earth will be reversed with the  earth closest to the Sun during northern hemisphere’s summer and farthest during northern hemisphere’s winter. 
  •  Precession is the wobble of the earth’s tilt in relation to the seasons.  Right now, the earth is farthest to the Sun during northern hemisphere’s summer and nearest during northern hemisphere’s winter. However, in another 20,000 years, the earth will be reversed with the  earth closest to the Sun during northern hemisphere’s summer and farthest during northern hemisphere’s winter. 
  •  Precession is the wobble of the earth’s tilt in relation to the seasons.  Right now, the earth is farthest to the Sun during northern hemisphere’s summer and nearest during northern hemisphere’s winter. However, in another 20,000 years, the earth will be reversed with the  earth closest to the Sun during northern hemisphere’s summer and farthest during northern hemisphere’s winter. 
  •  Precession is the wobble of the earth’s tilt in relation to the seasons.  Right now, the earth is farthest to the Sun during northern hemisphere’s summer and nearest during northern hemisphere’s winter. However, in another 20,000 years, the earth will be reversed with the  earth closest to the Sun during northern hemisphere’s summer and farthest during northern hemisphere’s winter. 
  • The second orbital parameter is obliquity or tilt. The earth’s tilt goes from a  minimum of 22.5° to a  maximum of 24.5°. The current tilt is 23.5°. 
  • The second orbital parameter is obliquity or tilt. The earth’s tilt goes from a  minimum of 22.5° to a  maximum of 24.5°. The current tilt is 23.5°. 
  • The second orbital parameter is obliquity or tilt. The earth’s tilt goes from a  minimum of 22.5° to a  maximum of 24.5°. The current tilt is 23.5°. 
  • The third orbital parameter is eccentricity, which is a measure of the elliptical nature of the earth’s orbit.  The maximum eccentricity is 0.061 and  the minimum eccentricity is 0.005. You should note that these drawings are not to scale.  The maximum eccentricity of the earth’s orbit drawn to scale looks like this! 
  • The third orbital parameter is eccentricity, which is a measure of the elliptical nature of the earth’s orbit.  The maximum eccentricity is 0.061 and  the minimum eccentricity is 0.005. You should note that these drawings are not to scale.  The maximum eccentricity of the earth’s orbit drawn to scale looks like this! 
  • The third orbital parameter is eccentricity, which is a measure of the elliptical nature of the earth’s orbit.  The maximum eccentricity is 0.061 and  the minimum eccentricity is 0.005. You should note that these drawings are not to scale.  The maximum eccentricity of the earth’s orbit drawn to scale looks like this! 
  • The third orbital parameter is eccentricity, which is a measure of the elliptical nature of the earth’s orbit.  The maximum eccentricity is 0.061 and  the minimum eccentricity is 0.005. You should note that these drawings are not to scale.  The maximum eccentricity of the earth’s orbit drawn to scale looks like this! 
  • The third orbital parameter is eccentricity, which is a measure of the elliptical nature of the earth’s orbit.  The maximum eccentricity is 0.061 and  the minimum eccentricity is 0.005. You should note that these drawings are not to scale.  The maximum eccentricity of the earth’s orbit drawn to scale looks like this! 
  • The third orbital parameter is eccentricity, which is a measure of the elliptical nature of the earth’s orbit.  The maximum eccentricity is 0.061 and  the minimum eccentricity is 0.005. You should note that these drawings are not to scale.  The maximum eccentricity of the earth’s orbit drawn to scale looks like this! 
  • The third orbital parameter is eccentricity, which is a measure of the elliptical nature of the earth’s orbit.  The maximum eccentricity is 0.061 and  the minimum eccentricity is 0.005. You should note that these drawings are not to scale.  The maximum eccentricity of the earth’s orbit drawn to scale looks like this! 
  • The third orbital parameter is eccentricity, which is a measure of the elliptical nature of the earth’s orbit.  The maximum eccentricity is 0.061 and  the minimum eccentricity is 0.005. You should note that these drawings are not to scale.  The maximum eccentricity of the earth’s orbit drawn to scale looks like this! 
  • The third orbital parameter is eccentricity, which is a measure of the elliptical nature of the earth’s orbit.  The maximum eccentricity is 0.061 and  the minimum eccentricity is 0.005. You should note that these drawings are not to scale.  The maximum eccentricity of the earth’s orbit drawn to scale looks like this! 
  • The third orbital parameter is eccentricity, which is a measure of the elliptical nature of the earth’s orbit.  The maximum eccentricity is 0.061 and  the minimum eccentricity is 0.005. You should note that these drawings are not to scale.  The maximum eccentricity of the earth’s orbit drawn to scale looks like this! 
  • The third orbital parameter is eccentricity, which is a measure of the elliptical nature of the earth’s orbit.  The maximum eccentricity is 0.061 and  the minimum eccentricity is 0.005. You should note that these drawings are not to scale.  The maximum eccentricity of the earth’s orbit drawn to scale looks like this! 
  • The third orbital parameter is eccentricity, which is a measure of the elliptical nature of the earth’s orbit.  The maximum eccentricity is 0.061 and  the minimum eccentricity is 0.005. You should note that these drawings are not to scale.  The maximum eccentricity of the earth’s orbit drawn to scale looks like this! 
  • The third orbital parameter is eccentricity, which is a measure of the elliptical nature of the earth’s orbit.  The maximum eccentricity is 0.061 and  the minimum eccentricity is 0.005. You should note that these drawings are not to scale.  The maximum eccentricity of the earth’s orbit drawn to scale looks like this! 
  • The third orbital parameter is eccentricity, which is a measure of the elliptical nature of the earth’s orbit.  The maximum eccentricity is 0.061 and  the minimum eccentricity is 0.005. You should note that these drawings are not to scale.  The maximum eccentricity of the earth’s orbit drawn to scale looks like this! 
  • The third orbital parameter is eccentricity, which is a measure of the elliptical nature of the earth’s orbit.  The maximum eccentricity is 0.061 and  the minimum eccentricity is 0.005. You should note that these drawings are not to scale.  The maximum eccentricity of the earth’s orbit drawn to scale looks like this! 
  • The third orbital parameter is eccentricity, which is a measure of the elliptical nature of the earth’s orbit.  The maximum eccentricity is 0.061 and  the minimum eccentricity is 0.005. You should note that these drawings are not to scale.  The maximum eccentricity of the earth’s orbit drawn to scale looks like this! 
  • So how do these orbital variations play out over time?  Precession cycles over a period of ~22 ky.  Obliquity cycles every 41 ky. And  eccentricity cycles every 100 ky.  The bottom curve represents the earth’s temperature over this same period of time. As can be seen, the cycles of glaciation closely match the earth’s cycles of eccentricity. 
  • So how do these orbital variations play out over time?  Precession cycles over a period of ~22 ky.  Obliquity cycles every 41 ky. And  eccentricity cycles every 100 ky.  The bottom curve represents the earth’s temperature over this same period of time. As can be seen, the cycles of glaciation closely match the earth’s cycles of eccentricity. 
  • So how do these orbital variations play out over time?  Precession cycles over a period of ~22 ky.  Obliquity cycles every 41 ky. And  eccentricity cycles every 100 ky.  The bottom curve represents the earth’s temperature over this same period of time. As can be seen, the cycles of glaciation closely match the earth’s cycles of eccentricity. 
  • So how do these orbital variations play out over time?  Precession cycles over a period of ~22 ky.  Obliquity cycles every 41 ky. And  eccentricity cycles every 100 ky.  The bottom curve represents the earth’s temperature over this same period of time. As can be seen, the cycles of glaciation closely match the earth’s cycles of eccentricity. 
  • So how do these orbital variations play out over time?  Precession cycles over a period of ~22 ky.  Obliquity cycles every 41 ky. And  eccentricity cycles every 100 ky.  The bottom curve represents the earth’s temperature over this same period of time. As can be seen, the cycles of glaciation closely match the earth’s cycles of eccentricity. 
  • So how do these orbital variations play out over time?  Precession cycles over a period of ~22 ky.  Obliquity cycles every 41 ky. And  eccentricity cycles every 100 ky.  The bottom curve represents the earth’s temperature over this same period of time. As can be seen, the cycles of glaciation closely match the earth’s cycles of eccentricity. 
  • So how do these orbital variations play out over time?  Precession cycles over a period of ~22 ky.  Obliquity cycles every 41 ky. And  eccentricity cycles every 100 ky.  The bottom curve represents the earth’s temperature over this same period of time. As can be seen, the cycles of glaciation closely match the earth’s cycles of eccentricity. 
  • So how do these orbital variations play out over time?  Precession cycles over a period of ~22 ky.  Obliquity cycles every 41 ky. And  eccentricity cycles every 100 ky.  The bottom curve represents the earth’s temperature over this same period of time. As can be seen, the cycles of glaciation closely match the earth’s cycles of eccentricity. 
  • So how do these orbital variations play out over time?  Precession cycles over a period of ~22 ky.  Obliquity cycles every 41 ky. And  eccentricity cycles every 100 ky.  The bottom curve represents the earth’s temperature over this same period of time. As can be seen, the cycles of glaciation closely match the earth’s cycles of eccentricity. 
  • So how do these orbital variations play out over time?  Precession cycles over a period of ~22 ky.  Obliquity cycles every 41 ky. And  eccentricity cycles every 100 ky.  The bottom curve represents the earth’s temperature over this same period of time. As can be seen, the cycles of glaciation closely match the earth’s cycles of eccentricity. 
  • So how do these orbital variations play out over time?  Precession cycles over a period of ~22 ky.  Obliquity cycles every 41 ky. And  eccentricity cycles every 100 ky.  The bottom curve represents the earth’s temperature over this same period of time. As can be seen, the cycles of glaciation closely match the earth’s cycles of eccentricity. 
  • So how do these orbital variations play out over time?  Precession cycles over a period of ~22 ky.  Obliquity cycles every 41 ky. And  eccentricity cycles every 100 ky.  The bottom curve represents the earth’s temperature over this same period of time. As can be seen, the cycles of glaciation closely match the earth’s cycles of eccentricity. 
  • So how do these orbital variations play out over time?  Precession cycles over a period of ~22 ky.  Obliquity cycles every 41 ky. And  eccentricity cycles every 100 ky.  The bottom curve represents the earth’s temperature over this same period of time. As can be seen, the cycles of glaciation closely match the earth’s cycles of eccentricity. 
  • So how do these orbital variations play out over time?  Precession cycles over a period of ~22 ky.  Obliquity cycles every 41 ky. And  eccentricity cycles every 100 ky.  The bottom curve represents the earth’s temperature over this same period of time. As can be seen, the cycles of glaciation closely match the earth’s cycles of eccentricity. 
  • So how do these orbital variations play out over time?  Precession cycles over a period of ~22 ky.  Obliquity cycles every 41 ky. And  eccentricity cycles every 100 ky.  The bottom curve represents the earth’s temperature over this same period of time. As can be seen, the cycles of glaciation closely match the earth’s cycles of eccentricity. 
  • The last ice age began to thaw 15,000 years ago, but was interrupted by the “Younger Dryas” event 12,900 years ago. 
  • The last ice age began to thaw 15,000 years ago, but was interrupted by the “Younger Dryas” event 12,900 years ago. 
  •  This graph shows temperatures and snow accumulation in Greenland for the last 20 ky.  The last ice age began to thaw  15 kya, but was interrupted by a  period of cooling, leading to the  Younger Dryas Event.  At 12,900 ya there was a period of rapid warming leading into our current interglacial period.  This period has been characterized by ~1,500 year periods of warming and cooling, with the  last warm period being known as the Medieval warm period and the  last cool period being known as the “Little Ice Age”. 
  •  This graph shows temperatures and snow accumulation in Greenland for the last 20 ky.  The last ice age began to thaw  15 kya, but was interrupted by a  period of cooling, leading to the  Younger Dryas Event.  At 12,900 ya there was a period of rapid warming leading into our current interglacial period.  This period has been characterized by ~1,500 year periods of warming and cooling, with the  last warm period being known as the Medieval warm period and the  last cool period being known as the “Little Ice Age”. 
  •  This graph shows temperatures and snow accumulation in Greenland for the last 20 ky.  The last ice age began to thaw  15 kya, but was interrupted by a  period of cooling, leading to the  Younger Dryas Event.  At 12,900 ya there was a period of rapid warming leading into our current interglacial period.  This period has been characterized by ~1,500 year periods of warming and cooling, with the  last warm period being known as the Medieval warm period and the  last cool period being known as the “Little Ice Age”. 
  •  This graph shows temperatures and snow accumulation in Greenland for the last 20 ky.  The last ice age began to thaw  15 kya, but was interrupted by a  period of cooling, leading to the  Younger Dryas Event.  At 12,900 ya there was a period of rapid warming leading into our current interglacial period.  This period has been characterized by ~1,500 year periods of warming and cooling, with the  last warm period being known as the Medieval warm period and the  last cool period being known as the “Little Ice Age”. 
  •  This graph shows temperatures and snow accumulation in Greenland for the last 20 ky.  The last ice age began to thaw  15 kya, but was interrupted by a  period of cooling, leading to the  Younger Dryas Event.  At 12,900 ya there was a period of rapid warming leading into our current interglacial period.  This period has been characterized by ~1,500 year periods of warming and cooling, with the  last warm period being known as the Medieval warm period and the  last cool period being known as the “Little Ice Age”. 
  •  This graph shows temperatures and snow accumulation in Greenland for the last 20 ky.  The last ice age began to thaw  15 kya, but was interrupted by a  period of cooling, leading to the  Younger Dryas Event.  At 12,900 ya there was a period of rapid warming leading into our current interglacial period.  This period has been characterized by ~1,500 year periods of warming and cooling, with the  last warm period being known as the Medieval warm period and the  last cool period being known as the “Little Ice Age”. 
  •  This graph shows temperatures and snow accumulation in Greenland for the last 20 ky.  The last ice age began to thaw  15 kya, but was interrupted by a  period of cooling, leading to the  Younger Dryas Event.  At 12,900 ya there was a period of rapid warming leading into our current interglacial period.  This period has been characterized by ~1,500 year periods of warming and cooling, with the  last warm period being known as the Medieval warm period and the  last cool period being known as the “Little Ice Age”. 
  •  This graph shows temperatures and snow accumulation in Greenland for the last 20 ky.  The last ice age began to thaw  15 kya, but was interrupted by a  period of cooling, leading to the  Younger Dryas Event.  At 12,900 ya there was a period of rapid warming leading into our current interglacial period.  This period has been characterized by ~1,500 year periods of warming and cooling, with the  last warm period being known as the Medieval warm period and the  last cool period being known as the “Little Ice Age”. 
  •  This graph shows temperatures and snow accumulation in Greenland for the last 20 ky.  The last ice age began to thaw  15 kya, but was interrupted by a  period of cooling, leading to the  Younger Dryas Event.  At 12,900 ya there was a period of rapid warming leading into our current interglacial period.  This period has been characterized by ~1,500 year periods of warming and cooling, with the  last warm period being known as the Medieval warm period and the  last cool period being known as the “Little Ice Age”. 
  •  This graph shows temperatures and snow accumulation in Greenland for the last 20 ky.  The last ice age began to thaw  15 kya, but was interrupted by a  period of cooling, leading to the  Younger Dryas Event.  At 12,900 ya there was a period of rapid warming leading into our current interglacial period.  This period has been characterized by ~1,500 year periods of warming and cooling, with the  last warm period being known as the Medieval warm period and the  last cool period being known as the “Little Ice Age”. 
  •  This graph shows temperatures and snow accumulation in Greenland for the last 20 ky.  The last ice age began to thaw  15 kya, but was interrupted by a  period of cooling, leading to the  Younger Dryas Event.  At 12,900 ya there was a period of rapid warming leading into our current interglacial period.  This period has been characterized by ~1,500 year periods of warming and cooling, with the  last warm period being known as the Medieval warm period and the  last cool period being known as the “Little Ice Age”. 
  •  This graph shows temperatures and snow accumulation in Greenland for the last 20 ky.  The last ice age began to thaw  15 kya, but was interrupted by a  period of cooling, leading to the  Younger Dryas Event.  At 12,900 ya there was a period of rapid warming leading into our current interglacial period.  This period has been characterized by ~1,500 year periods of warming and cooling, with the  last warm period being known as the Medieval warm period and the  last cool period being known as the “Little Ice Age”. 
  •  This graph shows temperatures and snow accumulation in Greenland for the last 20 ky.  The last ice age began to thaw  15 kya, but was interrupted by a  period of cooling, leading to the  Younger Dryas Event.  At 12,900 ya there was a period of rapid warming leading into our current interglacial period.  This period has been characterized by ~1,500 year periods of warming and cooling, with the  last warm period being known as the Medieval warm period and the  last cool period being known as the “Little Ice Age”. 
  •  This graph shows temperatures and snow accumulation in Greenland for the last 20 ky.  The last ice age began to thaw  15 kya, but was interrupted by a  period of cooling, leading to the  Younger Dryas Event.  At 12,900 ya there was a period of rapid warming leading into our current interglacial period.  This period has been characterized by ~1,500 year periods of warming and cooling, with the  last warm period being known as the Medieval warm period and the  last cool period being known as the “Little Ice Age”. 
  •  This graph shows temperatures and snow accumulation in Greenland for the last 20 ky.  The last ice age began to thaw  15 kya, but was interrupted by a  period of cooling, leading to the  Younger Dryas Event.  At 12,900 ya there was a period of rapid warming leading into our current interglacial period.  This period has been characterized by ~1,500 year periods of warming and cooling, with the  last warm period being known as the Medieval warm period and the  last cool period being known as the “Little Ice Age”. 
  •  This graph shows temperatures and snow accumulation in Greenland for the last 20 ky.  The last ice age began to thaw  15 kya, but was interrupted by a  period of cooling, leading to the  Younger Dryas Event.  At 12,900 ya there was a period of rapid warming leading into our current interglacial period.  This period has been characterized by ~1,500 year periods of warming and cooling, with the  last warm period being known as the Medieval warm period and the  last cool period being known as the “Little Ice Age”. 
  •  This graph shows temperatures and snow accumulation in Greenland for the last 20 ky.  The last ice age began to thaw  15 kya, but was interrupted by a  period of cooling, leading to the  Younger Dryas Event.  At 12,900 ya there was a period of rapid warming leading into our current interglacial period.  This period has been characterized by ~1,500 year periods of warming and cooling, with the  last warm period being known as the Medieval warm period and the  last cool period being known as the “Little Ice Age”. 
  •  This graph shows temperatures and snow accumulation in Greenland for the last 20 ky.  The last ice age began to thaw  15 kya, but was interrupted by a  period of cooling, leading to the  Younger Dryas Event.  At 12,900 ya there was a period of rapid warming leading into our current interglacial period.  This period has been characterized by ~1,500 year periods of warming and cooling, with the  last warm period being known as the Medieval warm period and the  last cool period being known as the “Little Ice Age”. 
  •  This graph shows temperatures and snow accumulation in Greenland for the last 20 ky.  The last ice age began to thaw  15 kya, but was interrupted by a  period of cooling, leading to the  Younger Dryas Event.  At 12,900 ya there was a period of rapid warming leading into our current interglacial period.  This period has been characterized by ~1,500 year periods of warming and cooling, with the  last warm period being known as the Medieval warm period and the  last cool period being known as the “Little Ice Age”. 
  •  This graph shows temperatures and snow accumulation in Greenland for the last 20 ky.  The last ice age began to thaw  15 kya, but was interrupted by a  period of cooling, leading to the  Younger Dryas Event.  At 12,900 ya there was a period of rapid warming leading into our current interglacial period.  This period has been characterized by ~1,500 year periods of warming and cooling, with the  last warm period being known as the Medieval warm period and the  last cool period being known as the “Little Ice Age”. 
  • The Younger Dryas event was not restricted to  Greenland, but can also be seen in proxy records from  China, shown here in blue. This data shows that it was a worldwide phenomenon. 
  • The Younger Dryas event was not restricted to  Greenland, but can also be seen in proxy records from  China, shown here in blue. This data shows that it was a worldwide phenomenon. 
  • During the
    Middle Pliocene (from 3.15 to 2.85 million ya) 
    temperatures were an average of 2°C higher than today, 
    but up to 20°C higher at high latitudes, 
    and only 1°C higher at the Equator. 
    In addition, sea levels were 100 ft higher. 
    The warmer climate of this era most likely resulted from 
    carbon dioxide levels that were 100 ppm higher than today, 
    and increased thermohaline circulation 
  • During the
    Middle Pliocene (from 3.15 to 2.85 million ya) 
    temperatures were an average of 2°C higher than today, 
    but up to 20°C higher at high latitudes, 
    and only 1°C higher at the Equator. 
    In addition, sea levels were 100 ft higher. 
    The warmer climate of this era most likely resulted from 
    carbon dioxide levels that were 100 ppm higher than today, 
    and increased thermohaline circulation 
  • During the
    Middle Pliocene (from 3.15 to 2.85 million ya) 
    temperatures were an average of 2°C higher than today, 
    but up to 20°C higher at high latitudes, 
    and only 1°C higher at the Equator. 
    In addition, sea levels were 100 ft higher. 
    The warmer climate of this era most likely resulted from 
    carbon dioxide levels that were 100 ppm higher than today, 
    and increased thermohaline circulation 
  • During the
    Middle Pliocene (from 3.15 to 2.85 million ya) 
    temperatures were an average of 2°C higher than today, 
    but up to 20°C higher at high latitudes, 
    and only 1°C higher at the Equator. 
    In addition, sea levels were 100 ft higher. 
    The warmer climate of this era most likely resulted from 
    carbon dioxide levels that were 100 ppm higher than today, 
    and increased thermohaline circulation 
  • During the
    Middle Pliocene (from 3.15 to 2.85 million ya) 
    temperatures were an average of 2°C higher than today, 
    but up to 20°C higher at high latitudes, 
    and only 1°C higher at the Equator. 
    In addition, sea levels were 100 ft higher. 
    The warmer climate of this era most likely resulted from 
    carbon dioxide levels that were 100 ppm higher than today, 
    and increased thermohaline circulation 
  • During the
    Middle Pliocene (from 3.15 to 2.85 million ya) 
    temperatures were an average of 2°C higher than today, 
    but up to 20°C higher at high latitudes, 
    and only 1°C higher at the Equator. 
    In addition, sea levels were 100 ft higher. 
    The warmer climate of this era most likely resulted from 
    carbon dioxide levels that were 100 ppm higher than today, 
    and increased thermohaline circulation 
  • During the
    Middle Pliocene (from 3.15 to 2.85 million ya) 
    temperatures were an average of 2°C higher than today, 
    but up to 20°C higher at high latitudes, 
    and only 1°C higher at the Equator. 
    In addition, sea levels were 100 ft higher. 
    The warmer climate of this era most likely resulted from 
    carbon dioxide levels that were 100 ppm higher than today, 
    and increased thermohaline circulation 
  • During the
    Middle Pliocene (from 3.15 to 2.85 million ya) 
    temperatures were an average of 2°C higher than today, 
    but up to 20°C higher at high latitudes, 
    and only 1°C higher at the Equator. 
    In addition, sea levels were 100 ft higher. 
    The warmer climate of this era most likely resulted from 
    carbon dioxide levels that were 100 ppm higher than today, 
    and increased thermohaline circulation 
  • Cooler temperatures were present during the 
    Eocene period (about 41 million years ago) 
    The opening of the Drake Passage (between South America and Antarctica) 
    Led to in increased ocean current exchange 
    Resulting in strong global cooling 
    And the first permanent glaciation of Antarctica ~34 million years ago 
  • Cooler temperatures were present during the 
    Eocene period (about 41 million years ago) 
    The opening of the Drake Passage (between South America and Antarctica) 
    Led to in increased ocean current exchange 
    Resulting in strong global cooling 
    And the first permanent glaciation of Antarctica ~34 million years ago 
  • Cooler temperatures were present during the 
    Eocene period (about 41 million years ago) 
    The opening of the Drake Passage (between South America and Antarctica) 
    Led to in increased ocean current exchange 
    Resulting in strong global cooling 
    And the first permanent glaciation of Antarctica ~34 million years ago 
  • Cooler temperatures were present during the 
    Eocene period (about 41 million years ago) 
    The opening of the Drake Passage (between South America and Antarctica) 
    Led to in increased ocean current exchange 
    Resulting in strong global cooling 
    And the first permanent glaciation of Antarctica ~34 million years ago 
  • Cooler temperatures were present during the 
    Eocene period (about 41 million years ago) 
    The opening of the Drake Passage (between South America and Antarctica) 
    Led to in increased ocean current exchange 
    Resulting in strong global cooling 
    And the first permanent glaciation of Antarctica ~34 million years ago 
  • During the 
    Paleocene Thermal Maximum (about 55 mya), 
    sea surface temperatures rose between 5 and 8°C. 
    This warming was probably caused by 
    increased volcanism 
    and a rapid release of methane from the oceans 
  • During the 
    Paleocene Thermal Maximum (about 55 mya), 
    sea surface temperatures rose between 5 and 8°C. 
    This warming was probably caused by 
    increased volcanism 
    and a rapid release of methane from the oceans 
  • During the 
    Paleocene Thermal Maximum (about 55 mya), 
    sea surface temperatures rose between 5 and 8°C. 
    This warming was probably caused by 
    increased volcanism 
    and a rapid release of methane from the oceans 
  • During the 
    Paleocene Thermal Maximum (about 55 mya), 
    sea surface temperatures rose between 5 and 8°C. 
    This warming was probably caused by 
    increased volcanism 
    and a rapid release of methane from the oceans 
  • During the 
    Paleocene Thermal Maximum (about 55 mya), 
    sea surface temperatures rose between 5 and 8°C. 
    This warming was probably caused by 
    increased volcanism 
    and a rapid release of methane from the oceans 
  • During the 
    Mid-Cretaceous period (about 120-90 mya) 
    Temperatures were much warmer than today and 
    Breadfruit trees grew as far north as Greenland 
    This period was much warmer due to 
    different ocean currents, because of the arrangement of continents 
    and higher CO2 levels, which were at least 2 to 4 times higher than today, up to 1200 ppm. 
  • During the 
    Mid-Cretaceous period (about 120-90 mya) 
    Temperatures were much warmer than today and 
    Breadfruit trees grew as far north as Greenland 
    This period was much warmer due to 
    different ocean currents, because of the arrangement of continents 
    and higher CO2 levels, which were at least 2 to 4 times higher than today, up to 1200 ppm. 
  • During the 
    Mid-Cretaceous period (about 120-90 mya) 
    Temperatures were much warmer than today and 
    Breadfruit trees grew as far north as Greenland 
    This period was much warmer due to 
    different ocean currents, because of the arrangement of continents 
    and higher CO2 levels, which were at least 2 to 4 times higher than today, up to 1200 ppm. 
  • During the 
    Mid-Cretaceous period (about 120-90 mya) 
    Temperatures were much warmer than today and 
    Breadfruit trees grew as far north as Greenland 
    This period was much warmer due to 
    different ocean currents, because of the arrangement of continents 
    and higher CO2 levels, which were at least 2 to 4 times higher than today, up to 1200 ppm. 
  • During the 
    Mid-Cretaceous period (about 120-90 mya) 
    Temperatures were much warmer than today and 
    Breadfruit trees grew as far north as Greenland 
    This period was much warmer due to 
    different ocean currents, because of the arrangement of continents 
    and higher CO2 levels, which were at least 2 to 4 times higher than today, up to 1200 ppm. 
  • During the 
    Mid-Cretaceous period (about 120-90 mya) 
    Temperatures were much warmer than today and 
    Breadfruit trees grew as far north as Greenland 
    This period was much warmer due to 
    different ocean currents, because of the arrangement of continents 
    and higher CO2 levels, which were at least 2 to 4 times higher than today, up to 1200 ppm. 
  • This is a plot of carbon dioxide levels in the atmosphere over the last 450 million years estimated using different proxies. The data shows that, in the past carbon dioxide levels have been up to 10 times higher than they are today. During those times, there were no continental glaciers present on earth.
  • 
  • In 1998 and 1999, Michael Mann et al. published studies detailing his  proxy reconstruction of global temperatures for the last 1,000 years. The graph is basically flat,  other than the rapid increase of temperatures during the 20th century. The study received wide acclaim, especially after publication by the IPCC (Intergovernmental Panel on Climate Change) and is  now referred to as the “Hockey Stick Graph”.  The curve in pink represents actual temperatures measured over the last 120+ years. 
  • In 1998 and 1999, Michael Mann et al. published studies detailing his  proxy reconstruction of global temperatures for the last 1,000 years. The graph is basically flat,  other than the rapid increase of temperatures during the 20th century. The study received wide acclaim, especially after publication by the IPCC (Intergovernmental Panel on Climate Change) and is  now referred to as the “Hockey Stick Graph”.  The curve in pink represents actual temperatures measured over the last 120+ years. 
  • In 1998 and 1999, Michael Mann et al. published studies detailing his  proxy reconstruction of global temperatures for the last 1,000 years. The graph is basically flat,  other than the rapid increase of temperatures during the 20th century. The study received wide acclaim, especially after publication by the IPCC (Intergovernmental Panel on Climate Change) and is  now referred to as the “Hockey Stick Graph”.  The curve in pink represents actual temperatures measured over the last 120+ years. 
  • In 1998 and 1999, Michael Mann et al. published studies detailing his  proxy reconstruction of global temperatures for the last 1,000 years. The graph is basically flat,  other than the rapid increase of temperatures during the 20th century. The study received wide acclaim, especially after publication by the IPCC (Intergovernmental Panel on Climate Change) and is  now referred to as the “Hockey Stick Graph”.  The curve in pink represents actual temperatures measured over the last 120+ years. 
  • In 1998 and 1999, Michael Mann et al. published studies detailing his  proxy reconstruction of global temperatures for the last 1,000 years. The graph is basically flat,  other than the rapid increase of temperatures during the 20th century. The study received wide acclaim, especially after publication by the IPCC (Intergovernmental Panel on Climate Change) and is  now referred to as the “Hockey Stick Graph”.  The curve in pink represents actual temperatures measured over the last 120+ years. 
  • In 1998 and 1999, Michael Mann et al. published studies detailing his  proxy reconstruction of global temperatures for the last 1,000 years. The graph is basically flat,  other than the rapid increase of temperatures during the 20th century. The study received wide acclaim, especially after publication by the IPCC (Intergovernmental Panel on Climate Change) and is  now referred to as the “Hockey Stick Graph”.  The curve in pink represents actual temperatures measured over the last 120+ years. 
  • However, the problem with the graphs is that tree ring data from 1960 on does not match the instrument readings of temperature  So, we can see a large divergence in the Jones study  the Briffa study  and the Mann study. Since tree ring proxies underestimate actual temperatures after 1960, one must ask if they also underestimate the Medieval warm period temperatures. Here we see the actual proxy records,  which look more like a baseball bat than a hockey stick. 
  • However, the problem with the graphs is that tree ring data from 1960 on does not match the instrument readings of temperature  So, we can see a large divergence in the Jones study  the Briffa study  and the Mann study. Since tree ring proxies underestimate actual temperatures after 1960, one must ask if they also underestimate the Medieval warm period temperatures. Here we see the actual proxy records,  which look more like a baseball bat than a hockey stick. 
  • However, the problem with the graphs is that tree ring data from 1960 on does not match the instrument readings of temperature  So, we can see a large divergence in the Jones study  the Briffa study  and the Mann study. Since tree ring proxies underestimate actual temperatures after 1960, one must ask if they also underestimate the Medieval warm period temperatures. Here we see the actual proxy records,  which look more like a baseball bat than a hockey stick. 
  • However, the problem with the graphs is that tree ring data from 1960 on does not match the instrument readings of temperature  So, we can see a large divergence in the Jones study  the Briffa study  and the Mann study. Since tree ring proxies underestimate actual temperatures after 1960, one must ask if they also underestimate the Medieval warm period temperatures. Here we see the actual proxy records,  which look more like a baseball bat than a hockey stick. 
  • However, the problem with the graphs is that tree ring data from 1960 on does not match the instrument readings of temperature  So, we can see a large divergence in the Jones study  the Briffa study  and the Mann study. Since tree ring proxies underestimate actual temperatures after 1960, one must ask if they also underestimate the Medieval warm period temperatures. Here we see the actual proxy records,  which look more like a baseball bat than a hockey stick. 
  • However, the problem with the graphs is that tree ring data from 1960 on does not match the instrument readings of temperature  So, we can see a large divergence in the Jones study  the Briffa study  and the Mann study. Since tree ring proxies underestimate actual temperatures after 1960, one must ask if they also underestimate the Medieval warm period temperatures. Here we see the actual proxy records,  which look more like a baseball bat than a hockey stick. 
  • However, the problem with the graphs is that tree ring data from 1960 on does not match the instrument readings of temperature  So, we can see a large divergence in the Jones study  the Briffa study  and the Mann study. Since tree ring proxies underestimate actual temperatures after 1960, one must ask if they also underestimate the Medieval warm period temperatures. Here we see the actual proxy records,  which look more like a baseball bat than a hockey stick. 
  • However, the problem with the graphs is that tree ring data from 1960 on does not match the instrument readings of temperature  So, we can see a large divergence in the Jones study  the Briffa study  and the Mann study. Since tree ring proxies underestimate actual temperatures after 1960, one must ask if they also underestimate the Medieval warm period temperatures. Here we see the actual proxy records,  which look more like a baseball bat than a hockey stick. 
  • However, the problem with the graphs is that tree ring data from 1960 on does not match the instrument readings of temperature  So, we can see a large divergence in the Jones study  the Briffa study  and the Mann study. Since tree ring proxies underestimate actual temperatures after 1960, one must ask if they also underestimate the Medieval warm period temperatures. Here we see the actual proxy records,  which look more like a baseball bat than a hockey stick. 
  • However, the problem with the graphs is that tree ring data from 1960 on does not match the instrument readings of temperature  So, we can see a large divergence in the Jones study  the Briffa study  and the Mann study. Since tree ring proxies underestimate actual temperatures after 1960, one must ask if they also underestimate the Medieval warm period temperatures. Here we see the actual proxy records,  which look more like a baseball bat than a hockey stick. 
  • However, the problem with the graphs is that tree ring data from 1960 on does not match the instrument readings of temperature  So, we can see a large divergence in the Jones study  the Briffa study  and the Mann study. Since tree ring proxies underestimate actual temperatures after 1960, one must ask if they also underestimate the Medieval warm period temperatures. Here we see the actual proxy records,  which look more like a baseball bat than a hockey stick. 
  • However, the problem with the graphs is that tree ring data from 1960 on does not match the instrument readings of temperature  So, we can see a large divergence in the Jones study  the Briffa study  and the Mann study. Since tree ring proxies underestimate actual temperatures after 1960, one must ask if they also underestimate the Medieval warm period temperatures. Here we see the actual proxy records,  which look more like a baseball bat than a hockey stick. 
  • However, the problem with the graphs is that tree ring data from 1960 on does not match the instrument readings of temperature  So, we can see a large divergence in the Jones study  the Briffa study  and the Mann study. Since tree ring proxies underestimate actual temperatures after 1960, one must ask if they also underestimate the Medieval warm period temperatures. Here we see the actual proxy records,  which look more like a baseball bat than a hockey stick. 
  • However, the problem with the graphs is that tree ring data from 1960 on does not match the instrument readings of temperature  So, we can see a large divergence in the Jones study  the Briffa study  and the Mann study. Since tree ring proxies underestimate actual temperatures after 1960, one must ask if they also underestimate the Medieval warm period temperatures. Here we see the actual proxy records,  which look more like a baseball bat than a hockey stick. 
  • However, the problem with the graphs is that tree ring data from 1960 on does not match the instrument readings of temperature  So, we can see a large divergence in the Jones study  the Briffa study  and the Mann study. Since tree ring proxies underestimate actual temperatures after 1960, one must ask if they also underestimate the Medieval warm period temperatures. Here we see the actual proxy records,  which look more like a baseball bat than a hockey stick. 
  • However, the problem with the graphs is that tree ring data from 1960 on does not match the instrument readings of temperature  So, we can see a large divergence in the Jones study  the Briffa study  and the Mann study. Since tree ring proxies underestimate actual temperatures after 1960, one must ask if they also underestimate the Medieval warm period temperatures. Here we see the actual proxy records,  which look more like a baseball bat than a hockey stick. 
  • However, the problem with the graphs is that tree ring data from 1960 on does not match the instrument readings of temperature  So, we can see a large divergence in the Jones study  the Briffa study  and the Mann study. Since tree ring proxies underestimate actual temperatures after 1960, one must ask if they also underestimate the Medieval warm period temperatures. Here we see the actual proxy records,  which look more like a baseball bat than a hockey stick. 
  • However, the problem with the graphs is that tree ring data from 1960 on does not match the instrument readings of temperature  So, we can see a large divergence in the Jones study  the Briffa study  and the Mann study. Since tree ring proxies underestimate actual temperatures after 1960, one must ask if they also underestimate the Medieval warm period temperatures. Here we see the actual proxy records,  which look more like a baseball bat than a hockey stick. 
  •  Although  temperature increases the width of tree rings,  rainfall, and to a lesser extent  carbon dioxide, through a “fertilization effect” also increase the width of tree rings. So, the idea that tree rings are always an accurate representation of past temperatures is not always true. In other words, trees do not always make good thermometers. 
  •  Although  temperature increases the width of tree rings,  rainfall, and to a lesser extent  carbon dioxide, through a “fertilization effect” also increase the width of tree rings. So, the idea that tree rings are always an accurate representation of past temperatures is not always true. In other words, trees do not always make good thermometers. 
  •  Although  temperature increases the width of tree rings,  rainfall, and to a lesser extent  carbon dioxide, through a “fertilization effect” also increase the width of tree rings. So, the idea that tree rings are always an accurate representation of past temperatures is not always true. In other words, trees do not always make good thermometers. 
  •  A number of studies were published after the Mann study.  In 2002 Esper et al. published a study covering the same period of time, but with much higher variations of temperature over time.  So, although the ups and downs are roughly in the same place, the magnitudes of those ups and downs are vastly different. 
  •  A number of studies were published after the Mann study.  In 2002 Esper et al. published a study covering the same period of time, but with much higher variations of temperature over time.  So, although the ups and downs are roughly in the same place, the magnitudes of those ups and downs are vastly different. 
  •  A number of studies were published after the Mann study.  In 2002 Esper et al. published a study covering the same period of time, but with much higher variations of temperature over time.  So, although the ups and downs are roughly in the same place, the magnitudes of those ups and downs are vastly different. 
  •  A number of studies were published after the Mann study.  In 2002 Esper et al. published a study covering the same period of time, but with much higher variations of temperature over time.  So, although the ups and downs are roughly in the same place, the magnitudes of those ups and downs are vastly different. 
  •  A number of studies were published after the Mann study.  In 2002 Esper et al. published a study covering the same period of time, but with much higher variations of temperature over time.  So, although the ups and downs are roughly in the same place, the magnitudes of those ups and downs are vastly different. 
  •  A number of studies were published after the Mann study.  In 2002 Esper et al. published a study covering the same period of time, but with much higher variations of temperature over time.  So, although the ups and downs are roughly in the same place, the magnitudes of those ups and downs are vastly different. 
  •  A number of studies were published after the Mann study.  In 2002 Esper et al. published a study covering the same period of time, but with much higher variations of temperature over time.  So, although the ups and downs are roughly in the same place, the magnitudes of those ups and downs are vastly different. 
  • Again, the 1999 Mann study is shown in green.  Another study, by Moberg et al., using different proxy measures found higher magnitude differences in temperatures.  Here the results of Esper et al. are shown on the same scale. Several other studies have been published that fall between the extremes of these three studies.  Mann added multiple proxy data to his analysis in 2008, which showed higher variation than the 1999 study. So, some of these data suggest that the  Medieval Warm Period was as warm or warmer than today’s temperatures. 
  • Again, the 1999 Mann study is shown in green.  Another study, by Moberg et al., using different proxy measures found higher magnitude differences in temperatures.  Here the results of Esper et al. are shown on the same scale. Several other studies have been published that fall between the extremes of these three studies.  Mann added multiple proxy data to his analysis in 2008, which showed higher variation than the 1999 study. So, some of these data suggest that the  Medieval Warm Period was as warm or warmer than today’s temperatures. 
  • Again, the 1999 Mann study is shown in green.  Another study, by Moberg et al., using different proxy measures found higher magnitude differences in temperatures.  Here the results of Esper et al. are shown on the same scale. Several other studies have been published that fall between the extremes of these three studies.  Mann added multiple proxy data to his analysis in 2008, which showed higher variation than the 1999 study. So, some of these data suggest that the  Medieval Warm Period was as warm or warmer than today’s temperatures. 
  • Again, the 1999 Mann study is shown in green.  Another study, by Moberg et al., using different proxy measures found higher magnitude differences in temperatures.  Here the results of Esper et al. are shown on the same scale. Several other studies have been published that fall between the extremes of these three studies.  Mann added multiple proxy data to his analysis in 2008, which showed higher variation than the 1999 study. So, some of these data suggest that the  Medieval Warm Period was as warm or warmer than today’s temperatures. 
  • Again, the 1999 Mann study is shown in green.  Another study, by Moberg et al., using different proxy measures found higher magnitude differences in temperatures.  Here the results of Esper et al. are shown on the same scale. Several other studies have been published that fall between the extremes of these three studies.  Mann added multiple proxy data to his analysis in 2008, which showed higher variation than the 1999 study. So, some of these data suggest that the  Medieval Warm Period was as warm or warmer than today’s temperatures. 
  • Again, the 1999 Mann study is shown in green.  Another study, by Moberg et al., using different proxy measures found higher magnitude differences in temperatures.  Here the results of Esper et al. are shown on the same scale. Several other studies have been published that fall between the extremes of these three studies.  Mann added multiple proxy data to his analysis in 2008, which showed higher variation than the 1999 study. So, some of these data suggest that the  Medieval Warm Period was as warm or warmer than today’s temperatures. 
  • Again, the 1999 Mann study is shown in green.  Another study, by Moberg et al., using different proxy measures found higher magnitude differences in temperatures.  Here the results of Esper et al. are shown on the same scale. Several other studies have been published that fall between the extremes of these three studies.  Mann added multiple proxy data to his analysis in 2008, which showed higher variation than the 1999 study. So, some of these data suggest that the  Medieval Warm Period was as warm or warmer than today’s temperatures. 
  • In June, 2006, the U.S. National Academy of Sciences weighed in on the question of the Mann study.  They put a “high level of confidence” in the last 400 years of proxy results,  but only a 2:1 chance of being right for the first 600 years of data. 
  • In June, 2006, the U.S. National Academy of Sciences weighed in on the question of the Mann study.  They put a “high level of confidence” in the last 400 years of proxy results,  but only a 2:1 chance of being right for the first 600 years of data. 
  • Satellite temperature measurements of the lower and upper atmosphere have been carried out since 1980.  Temperatures of the troposphere show gradually increasing temperatures (although not as high as would be predicted),  and decreasing temperatures in the stratosphere, which would be expected under global warming models. 
  • Satellite temperature measurements of the lower and upper atmosphere have been carried out since 1980.  Temperatures of the troposphere show gradually increasing temperatures (although not as high as would be predicted),  and decreasing temperatures in the stratosphere, which would be expected under global warming models. 
  • Satellite temperature measurements of the lower and upper atmosphere have been carried out since 1980.  Temperatures of the troposphere show gradually increasing temperatures (although not as high as would be predicted),  and decreasing temperatures in the stratosphere, which would be expected under global warming models. 
  • Satellite temperature measurements of the lower and upper atmosphere have been carried out since 1980.  Temperatures of the troposphere show gradually increasing temperatures (although not as high as would be predicted),  and decreasing temperatures in the stratosphere, which would be expected under global warming models. 
  • Is there a correlation between carbon dioxide levels and temperatures? If we compare  carbon dioxide measurements from Antarctica with  sea surface temperatures from the tropical Pacific, we find that there is a high coincidence of carbon dioxide levels and temperatures in the past. 
  • Is there a correlation between carbon dioxide levels and temperatures? If we compare  carbon dioxide measurements from Antarctica with  sea surface temperatures from the tropical Pacific, we find that there is a high coincidence of carbon dioxide levels and temperatures in the past. 
  • 
  • If we examine global warming from the perspective of the two hemispheres, we find that  temperatures in the northern hemisphere have increased much more than  temperatures in the southern hemisphere. In a similar fashion,  temperatures over land masses have increased much more than  temperatures over the oceans. This is because the oceans tend to moderate temperature changes. So, since two thirds of the earth’s land mass is in the northern hemisphere, we would expect global warming to have its largest impact there. 
  • If we examine global warming from the perspective of the two hemispheres, we find that  temperatures in the northern hemisphere have increased much more than  temperatures in the southern hemisphere. In a similar fashion,  temperatures over land masses have increased much more than  temperatures over the oceans. This is because the oceans tend to moderate temperature changes. So, since two thirds of the earth’s land mass is in the northern hemisphere, we would expect global warming to have its largest impact there. 
  • If we examine global warming from the perspective of the two hemispheres, we find that  temperatures in the northern hemisphere have increased much more than  temperatures in the southern hemisphere. In a similar fashion,  temperatures over land masses have increased much more than  temperatures over the oceans. This is because the oceans tend to moderate temperature changes. So, since two thirds of the earth’s land mass is in the northern hemisphere, we would expect global warming to have its largest impact there. 
  • If we examine global warming from the perspective of the two hemispheres, we find that  temperatures in the northern hemisphere have increased much more than  temperatures in the southern hemisphere. In a similar fashion,  temperatures over land masses have increased much more than  temperatures over the oceans. This is because the oceans tend to moderate temperature changes. So, since two thirds of the earth’s land mass is in the northern hemisphere, we would expect global warming to have its largest impact there. 
  • If we examine global warming from the perspective of the two hemispheres, we find that  temperatures in the northern hemisphere have increased much more than  temperatures in the southern hemisphere. In a similar fashion,  temperatures over land masses have increased much more than  temperatures over the oceans. This is because the oceans tend to moderate temperature changes. So, since two thirds of the earth’s land mass is in the northern hemisphere, we would expect global warming to have its largest impact there. 
  • If we examine global warming from the perspective of the two hemispheres, we find that  temperatures in the northern hemisphere have increased much more than  temperatures in the southern hemisphere. In a similar fashion,  temperatures over land masses have increased much more than  temperatures over the oceans. This is because the oceans tend to moderate temperature changes. So, since two thirds of the earth’s land mass is in the northern hemisphere, we would expect global warming to have its largest impact there. 
  • If we examine global warming from the perspective of the two hemispheres, we find that  temperatures in the northern hemisphere have increased much more than  temperatures in the southern hemisphere. In a similar fashion,  temperatures over land masses have increased much more than  temperatures over the oceans. This is because the oceans tend to moderate temperature changes. So, since two thirds of the earth’s land mass is in the northern hemisphere, we would expect global warming to have its largest impact there. 
  • If we examine global warming from the perspective of the two hemispheres, we find that  temperatures in the northern hemisphere have increased much more than  temperatures in the southern hemisphere. In a similar fashion,  temperatures over land masses have increased much more than  temperatures over the oceans. This is because the oceans tend to moderate temperature changes. So, since two thirds of the earth’s land mass is in the northern hemisphere, we would expect global warming to have its largest impact there. 
  • If we examine global warming from the perspective of the two hemispheres, we find that  temperatures in the northern hemisphere have increased much more than  temperatures in the southern hemisphere. In a similar fashion,  temperatures over land masses have increased much more than  temperatures over the oceans. This is because the oceans tend to moderate temperature changes. So, since two thirds of the earth’s land mass is in the northern hemisphere, we would expect global warming to have its largest impact there. 
  • If we examine global warming from the perspective of the two hemispheres, we find that  temperatures in the northern hemisphere have increased much more than  temperatures in the southern hemisphere. In a similar fashion,  temperatures over land masses have increased much more than  temperatures over the oceans. This is because the oceans tend to moderate temperature changes. So, since two thirds of the earth’s land mass is in the northern hemisphere, we would expect global warming to have its largest impact there. 
  • If we examine global warming from the perspective of the two hemispheres, we find that  temperatures in the northern hemisphere have increased much more than  temperatures in the southern hemisphere. In a similar fashion,  temperatures over land masses have increased much more than  temperatures over the oceans. This is because the oceans tend to moderate temperature changes. So, since two thirds of the earth’s land mass is in the northern hemisphere, we would expect global warming to have its largest impact there. 
  • If we examine global warming from the perspective of the two hemispheres, we find that  temperatures in the northern hemisphere have increased much more than  temperatures in the southern hemisphere. In a similar fashion,  temperatures over land masses have increased much more than  temperatures over the oceans. This is because the oceans tend to moderate temperature changes. So, since two thirds of the earth’s land mass is in the northern hemisphere, we would expect global warming to have its largest impact there. 
  • Hence we see reason for the temperature changes seen in this graph. 
  • With these temperature increases, one main question is whether the ice sheets of Antarctica and Greenland are melting.    
  • With these temperature increases, one main question is whether the ice sheets of Antarctica and Greenland are melting.    
  • With these temperature increases, one main question is whether the ice sheets of Antarctica and Greenland are melting.    
  • With these temperature increases, one main question is whether the ice sheets of Antarctica and Greenland are melting.    
  • With these temperature increases, one main question is whether the ice sheets of Antarctica and Greenland are melting.    
  • Mount Kilimanjaro is the poster child of the global warming movement, since most of the glacier has disappeared over the last 30 years. However experts agree that the shrinking of the Mount Kilimanjaro glacier is more the result of deforestation of the surrounding area than changes due to global warming.
  • Mount Kilimanjaro is the poster child of the global warming movement, since most of the glacier has disappeared over the last 30 years. However experts agree that the shrinking of the Mount Kilimanjaro glacier is more the result of deforestation of the surrounding area than changes due to global warming.
  • These are the result of the GRACE study,  which show decreasing ice mass in Antarctica from 2002 to 2005. 
  • These are the result of the GRACE study,  which show decreasing ice mass in Antarctica from 2002 to 2005. 
  • Are sea levels rising? 
    The present measured rate is 1.8 mm/yr, which is equivalent to 7.4 in/century 
    Another study indicates that this rate is accelerating at 13 thousandths of a mm per year per year 
    If this acceleration continues, this could result in a 12 inch sea level rise in this century 
    Scenarios claiming a 1 meter or more rise in sea levels are unrealistic. 
  • Are sea levels rising? 
    The present measured rate is 1.8 mm/yr, which is equivalent to 7.4 in/century 
    Another study indicates that this rate is accelerating at 13 thousandths of a mm per year per year 
    If this acceleration continues, this could result in a 12 inch sea level rise in this century 
    Scenarios claiming a 1 meter or more rise in sea levels are unrealistic. 
  • Are sea levels rising? 
    The present measured rate is 1.8 mm/yr, which is equivalent to 7.4 in/century 
    Another study indicates that this rate is accelerating at 13 thousandths of a mm per year per year 
    If this acceleration continues, this could result in a 12 inch sea level rise in this century 
    Scenarios claiming a 1 meter or more rise in sea levels are unrealistic. 
  • Are sea levels rising? 
    The present measured rate is 1.8 mm/yr, which is equivalent to 7.4 in/century 
    Another study indicates that this rate is accelerating at 13 thousandths of a mm per year per year 
    If this acceleration continues, this could result in a 12 inch sea level rise in this century 
    Scenarios claiming a 1 meter or more rise in sea levels are unrealistic. 
  • Measurement of sea levels have been carried out for three European ports over the last few hundred years. The results can be seen for a  port in the Netherlands,  one in France,  and one in Poland.  When the sea level is compared to recorded temperatures over this period of time, the correlation is quite good. 
  • Measurement of sea levels have been carried out for three European ports over the last few hundred years. The results can be seen for a  port in the Netherlands,  one in France,  and one in Poland.  When the sea level is compared to recorded temperatures over this period of time, the correlation is quite good. 
  • Measurement of sea levels have been carried out for three European ports over the last few hundred years. The results can be seen for a  port in the Netherlands,  one in France,  and one in Poland.  When the sea level is compared to recorded temperatures over this period of time, the correlation is quite good. 
  • Measurement of sea levels have been carried out for three European ports over the last few hundred years. The results can be seen for a  port in the Netherlands,  one in France,  and one in Poland.  When the sea level is compared to recorded temperatures over this period of time, the correlation is quite good. 
  • Measurement of sea levels have been carried out for three European ports over the last few hundred years. The results can be seen for a  port in the Netherlands,  one in France,  and one in Poland.  When the sea level is compared to recorded temperatures over this period of time, the correlation is quite good. 
  • Measurement of sea levels have been carried out for three European ports over the last few hundred years. The results can be seen for a  port in the Netherlands,  one in France,  and one in Poland.  When the sea level is compared to recorded temperatures over this period of time, the correlation is quite good. 
  • This graph shows  sea levels of the Red Sea over the last 450,000 years. If we overlay  sea surface temperatures, we can see a direct correlation between sea levels and temperature. In fact, some of the rise in sea levels is due to the expansion of water at higher temperatures, and not solely due to the melting of ice. 
  • This graph shows  sea levels of the Red Sea over the last 450,000 years. If we overlay  sea surface temperatures, we can see a direct correlation between sea levels and temperature. In fact, some of the rise in sea levels is due to the expansion of water at higher temperatures, and not solely due to the melting of ice. 
  • The year 2005 was marked by a number of destructive hurricanes. What this just an unusual year or a trend that has resulted from climate change? 
    Two studies showed the total number of hurricanes has not changed 
    However, the intensity of hurricanes has increased (more category 4 and 5 hurricanes and cyclones) 
    This increase in intensity is probably due to higher sea surface temperatures, which provide more energy to the storms. 
    However, it is difficult to know if this trend will continue. 
  • The year 2005 was marked by a number of destructive hurricanes. What this just an unusual year or a trend that has resulted from climate change? 
    Two studies showed the total number of hurricanes has not changed 
    However, the intensity of hurricanes has increased (more category 4 and 5 hurricanes and cyclones) 
    This increase in intensity is probably due to higher sea surface temperatures, which provide more energy to the storms. 
    However, it is difficult to know if this trend will continue. 
  • The year 2005 was marked by a number of destructive hurricanes. What this just an unusual year or a trend that has resulted from climate change? 
    Two studies showed the total number of hurricanes has not changed 
    However, the intensity of hurricanes has increased (more category 4 and 5 hurricanes and cyclones) 
    This increase in intensity is probably due to higher sea surface temperatures, which provide more energy to the storms. 
    However, it is difficult to know if this trend will continue. 
  • The year 2005 was marked by a number of destructive hurricanes. What this just an unusual year or a trend that has resulted from climate change? 
    Two studies showed the total number of hurricanes has not changed 
    However, the intensity of hurricanes has increased (more category 4 and 5 hurricanes and cyclones) 
    This increase in intensity is probably due to higher sea surface temperatures, which provide more energy to the storms. 
    However, it is difficult to know if this trend will continue. 
  • The year 2005 was marked by a number of destructive hurricanes. What this just an unusual year or a trend that has resulted from climate change? 
    Two studies showed the total number of hurricanes has not changed 
    However, the intensity of hurricanes has increased (more category 4 and 5 hurricanes and cyclones) 
    This increase in intensity is probably due to higher sea surface temperatures, which provide more energy to the storms. 
    However, it is difficult to know if this trend will continue. 
  • The year 2005 was marked by a number of destructive hurricanes. What this just an unusual year or a trend that has resulted from climate change? 
    Two studies showed the total number of hurricanes has not changed 
    However, the intensity of hurricanes has increased (more category 4 and 5 hurricanes and cyclones) 
    This increase in intensity is probably due to higher sea surface temperatures, which provide more energy to the storms. 
    However, it is difficult to know if this trend will continue. 
  • The year 2005 was marked by a number of destructive hurricanes. What this just an unusual year or a trend that has resulted from climate change? 
    Two studies showed the total number of hurricanes has not changed 
    However, the intensity of hurricanes has increased (more category 4 and 5 hurricanes and cyclones) 
    This increase in intensity is probably due to higher sea surface temperatures, which provide more energy to the storms. 
    However, it is difficult to know if this trend will continue. 
  • The year 2005 was marked by a number of destructive hurricanes. What this just an unusual year or a trend that has resulted from climate change? 
    Two studies showed the total number of hurricanes has not changed 
    However, the intensity of hurricanes has increased (more category 4 and 5 hurricanes and cyclones) 
    This increase in intensity is probably due to higher sea surface temperatures, which provide more energy to the storms. 
    However, it is difficult to know if this trend will continue. 
  • The year 2005 was marked by a number of destructive hurricanes. What this just an unusual year or a trend that has resulted from climate change? 
    Two studies showed the total number of hurricanes has not changed 
    However, the intensity of hurricanes has increased (more category 4 and 5 hurricanes and cyclones) 
    This increase in intensity is probably due to higher sea surface temperatures, which provide more energy to the storms. 
    However, it is difficult to know if this trend will continue. 
  • The year 2005 was marked by a number of destructive hurricanes. What this just an unusual year or a trend that has resulted from climate change? 
    Two studies showed the total number of hurricanes has not changed 
    However, the intensity of hurricanes has increased (more category 4 and 5 hurricanes and cyclones) 
    This increase in intensity is probably due to higher sea surface temperatures, which provide more energy to the storms. 
    However, it is difficult to know if this trend will continue. 
  • The year 2005 was marked by a number of destructive hurricanes. What this just an unusual year or a trend that has resulted from climate change? 
    Two studies showed the total number of hurricanes has not changed 
    However, the intensity of hurricanes has increased (more category 4 and 5 hurricanes and cyclones) 
    This increase in intensity is probably due to higher sea surface temperatures, which provide more energy to the storms. 
    However, it is difficult to know if this trend will continue. 
  • The year 2005 was marked by a number of destructive hurricanes. What this just an unusual year or a trend that has resulted from climate change? 
    Two studies showed the total number of hurricanes has not changed 
    However, the intensity of hurricanes has increased (more category 4 and 5 hurricanes and cyclones) 
    This increase in intensity is probably due to higher sea surface temperatures, which provide more energy to the storms. 
    However, it is difficult to know if this trend will continue. 
  • The year 2005 was marked by a number of destructive hurricanes. What this just an unusual year or a trend that has resulted from climate change? 
    Two studies showed the total number of hurricanes has not changed 
    However, the intensity of hurricanes has increased (more category 4 and 5 hurricanes and cyclones) 
    This increase in intensity is probably due to higher sea surface temperatures, which provide more energy to the storms. 
    However, it is difficult to know if this trend will continue. 
  • The year 2005 was marked by a number of destructive hurricanes. What this just an unusual year or a trend that has resulted from climate change? 
    Two studies showed the total number of hurricanes has not changed 
    However, the intensity of hurricanes has increased (more category 4 and 5 hurricanes and cyclones) 
    This increase in intensity is probably due to higher sea surface temperatures, which provide more energy to the storms. 
    However, it is difficult to know if this trend will continue. 
  • How much will temperatures increase in the future? 
    Some models propose up to 9°C increase this century 
    Two studies put the minimum at 1.5°C and maximum at 4.5°C or 6.2°C 
    Another study puts the minimum at 2.5°C 
  • How much will temperatures increase in the future? 
    Some models propose up to 9°C increase this century 
    Two studies put the minimum at 1.5°C and maximum at 4.5°C or 6.2°C 
    Another study puts the minimum at 2.5°C 
  • How much will temperatures increase in the future? 
    Some models propose up to 9°C increase this century 
    Two studies put the minimum at 1.5°C and maximum at 4.5°C or 6.2°C 
    Another study puts the minimum at 2.5°C 
  • Some species of wildlife could be greatly affected by global warming 
    For example, polar bears 
    require pack ice in order to hunt and live. 
    If all pack ice disappears, they might eventually go extinct in the wild. 
    Sea turtles 
    breed on the same islands as they are born on. 
    They could go extinct on some islands as beaches are flooded before new beaches are produced. 
    Other species may go extinct as rainfall patterns change throughout the world. 
  • Some species of wildlife could be greatly affected by global warming 
    For example, polar bears 
    require pack ice in order to hunt and live. 
    If all pack ice disappears, they might eventually go extinct in the wild. 
    Sea turtles 
    breed on the same islands as they are born on. 
    They could go extinct on some islands as beaches are flooded before new beaches are produced. 
    Other species may go extinct as rainfall patterns change throughout the world. 
  • Some species of wildlife could be greatly affected by global warming 
    For example, polar bears 
    require pack ice in order to hunt and live. 
    If all pack ice disappears, they might eventually go extinct in the wild. 
    Sea turtles 
    breed on the same islands as they are born on. 
    They could go extinct on some islands as beaches are flooded before new beaches are produced. 
    Other species may go extinct as rainfall patterns change throughout the world. 
  • Some species of wildlife could be greatly affected by global warming 
    For example, polar bears 
    require pack ice in order to hunt and live. 
    If all pack ice disappears, they might eventually go extinct in the wild. 
    Sea turtles 
    breed on the same islands as they are born on. 
    They could go extinct on some islands as beaches are flooded before new beaches are produced. 
    Other species may go extinct as rainfall patterns change throughout the world. 
  • Some species of wildlife could be greatly affected by global warming 
    For example, polar bears 
    require pack ice in order to hunt and live. 
    If all pack ice disappears, they might eventually go extinct in the wild. 
    Sea turtles 
    breed on the same islands as they are born on. 
    They could go extinct on some islands as beaches are flooded before new beaches are produced. 
    Other species may go extinct as rainfall patterns change throughout the world. 
  • Some species of wildlife could be greatly affected by global warming 
    For example, polar bears 
    require pack ice in order to hunt and live. 
    If all pack ice disappears, they might eventually go extinct in the wild. 
    Sea turtles 
    breed on the same islands as they are born on. 
    They could go extinct on some islands as beaches are flooded before new beaches are produced. 
    Other species may go extinct as rainfall patterns change throughout the world. 
  • Some species of wildlife could be greatly affected by global warming 
    For example, polar bears 
    require pack ice in order to hunt and live. 
    If all pack ice disappears, they might eventually go extinct in the wild. 
    Sea turtles 
    breed on the same islands as they are born on. 
    They could go extinct on some islands as beaches are flooded before new beaches are produced. 
    Other species may go extinct as rainfall patterns change throughout the world. 
  • Some species of wildlife could be greatly affected by global warming 
    For example, polar bears 
    require pack ice in order to hunt and live. 
    If all pack ice disappears, they might eventually go extinct in the wild. 
    Sea turtles 
    breed on the same islands as they are born on. 
    They could go extinct on some islands as beaches are flooded before new beaches are produced. 
    Other species may go extinct as rainfall patterns change throughout the world. 
  • Some species of wildlife could be greatly affected by global warming 
    For example, polar bears 
    require pack ice in order to hunt and live. 
    If all pack ice disappears, they might eventually go extinct in the wild. 
    Sea turtles 
    breed on the same islands as they are born on. 
    They could go extinct on some islands as beaches are flooded before new beaches are produced. 
    Other species may go extinct as rainfall patterns change throughout the world. 
  • Some species of wildlife could be greatly affected by global warming 
    For example, polar bears 
    require pack ice in order to hunt and live. 
    If all pack ice disappears, they might eventually go extinct in the wild. 
    Sea turtles 
    breed on the same islands as they are born on. 
    They could go extinct on some islands as beaches are flooded before new beaches are produced. 
    Other species may go extinct as rainfall patterns change throughout the world. 
  • Some species of wildlife could be greatly affected by global warming 
    For example, polar bears 
    require pack ice in order to hunt and live. 
    If all pack ice disappears, they might eventually go extinct in the wild. 
    Sea turtles 
    breed on the same islands as they are born on. 
    They could go extinct on some islands as beaches are flooded before new beaches are produced. 
    Other species may go extinct as rainfall patterns change throughout the world. 
  • Global warming will affect peoples throughout the world. For example, 
    Fewer deaths will result from cold weather, but more deaths will result from heat waves 
    Initially, decreased thermohaline circulation will result in 
    cooler temperatures in North Atlantic. 
    The CO2 fertilization effect will increase crop yields by up to 30% 
    Precipitation changes will result in 
    droughts and famine in some areas and 
    expanded arable land in Canada, Soviet Union 
  • Global warming will affect peoples throughout the world. For example, 
    Fewer deaths will result from cold weather, but more deaths will result from heat waves 
    Initially, decreased thermohaline circulation will result in 
    cooler temperatures in North Atlantic. 
    The CO2 fertilization effect will increase crop yields by up to 30% 
    Precipitation changes will result in 
    droughts and famine in some areas and 
    expanded arable land in Canada, Soviet Union 
  • Global warming will affect peoples throughout the world. For example, 
    Fewer deaths will result from cold weather, but more deaths will result from heat waves 
    Initially, decreased thermohaline circulation will result in 
    cooler temperatures in North Atlantic. 
    The CO2 fertilization effect will increase crop yields by up to 30% 
    Precipitation changes will result in 
    droughts and famine in some areas and 
    expanded arable land in Canada, Soviet Union 
  • Global warming will affect peoples throughout the world. For example, 
    Fewer deaths will result from cold weather, but more deaths will result from heat waves 
    Initially, decreased thermohaline circulation will result in 
    cooler temperatures in North Atlantic. 
    The CO2 fertilization effect will increase crop yields by up to 30% 
    Precipitation changes will result in 
    droughts and famine in some areas and 
    expanded arable land in Canada, Soviet Union 
  • This map represents possible changes in worldwide precipitation as a result of global warming.  Some areas (primarily in the northern latitudes) will experience increased precipitation, whereas  other areas will experience decreased precipitation. 
  • This map represents possible changes in worldwide precipitation as a result of global warming.  Some areas (primarily in the northern latitudes) will experience increased precipitation, whereas  other areas will experience decreased precipitation. 
  • This map represents possible changes in worldwide precipitation as a result of global warming.  Some areas (primarily in the northern latitudes) will experience increased precipitation, whereas  other areas will experience decreased precipitation. 
  • This map represents possible changes in worldwide precipitation as a result of global warming.  Some areas (primarily in the northern latitudes) will experience increased precipitation, whereas  other areas will experience decreased precipitation. 
  • This map represents possible changes in worldwide precipitation as a result of global warming.  Some areas (primarily in the northern latitudes) will experience increased precipitation, whereas  other areas will experience decreased precipitation. 
  • This map represents possible changes in worldwide precipitation as a result of global warming.  Some areas (primarily in the northern latitudes) will experience increased precipitation, whereas  other areas will experience decreased precipitation. 
  • This map represents possible changes in worldwide precipitation as a result of global warming.  Some areas (primarily in the northern latitudes) will experience increased precipitation, whereas  other areas will experience decreased precipitation. 
  • This map represents possible changes in worldwide precipitation as a result of global warming.  Some areas (primarily in the northern latitudes) will experience increased precipitation, whereas  other areas will experience decreased precipitation. 
  • This map represents possible changes in worldwide precipitation as a result of global warming.  Some areas (primarily in the northern latitudes) will experience increased precipitation, whereas  other areas will experience decreased precipitation. 
  • This map represents possible changes in worldwide precipitation as a result of global warming.  Some areas (primarily in the northern latitudes) will experience increased precipitation, whereas  other areas will experience decreased precipitation. 
  • This map represents possible changes in worldwide precipitation as a result of global warming.  Some areas (primarily in the northern latitudes) will experience increased precipitation, whereas  other areas will experience decreased precipitation. 
  • This map represents possible changes in worldwide precipitation as a result of global warming.  Some areas (primarily in the northern latitudes) will experience increased precipitation, whereas  other areas will experience decreased precipitation. 
  • This map represents possible changes in worldwide precipitation as a result of global warming.  Some areas (primarily in the northern latitudes) will experience increased precipitation, whereas  other areas will experience decreased precipitation. 
  • This map represents possible changes in worldwide precipitation as a result of global warming.  Some areas (primarily in the northern latitudes) will experience increased precipitation, whereas  other areas will experience decreased precipitation. 
  • This map represents possible changes in worldwide precipitation as a result of global warming.  Some areas (primarily in the northern latitudes) will experience increased precipitation, whereas  other areas will experience decreased precipitation. 
  • This map represents possible changes in worldwide precipitation as a result of global warming.  Some areas (primarily in the northern latitudes) will experience increased precipitation, whereas  other areas will experience decreased precipitation. 
  • This map represents possible changes in worldwide precipitation as a result of global warming.  Some areas (primarily in the northern latitudes) will experience increased precipitation, whereas  other areas will experience decreased precipitation. 
  • Africa's drought troubles began well before greenhouse gases increased to any appreciable degree. The inhabitants of Northern Africa have systematically cut down trees for firewood for thousands of years. The result has been that transpiration has decreased, decreasing rainfall and expanding the Sahara Desert. Similar deforestation is now occurring over much of Africa. The result is that the deserts of North, South and East Africa are expanding, leading to drought. Coupled with global warming induced changes in precipitation, it is likely that the peoples of much of Africa will be suffering from drought and starvation in the coming decades.
  • Africa's drought troubles began well before greenhouse gases increased to any appreciable degree. The inhabitants of Northern Africa have systematically cut down trees for firewood for thousands of years. The result has been that transpiration has decreased, decreasing rainfall and expanding the Sahara Desert. Similar deforestation is now occurring over much of Africa. The result is that the deserts of North, South and East Africa are expanding, leading to drought. Coupled with global warming induced changes in precipitation, it is likely that the peoples of much of Africa will be suffering from drought and starvation in the coming decades.
  • Africa's drought troubles began well before greenhouse gases increased to any appreciable degree. The inhabitants of Northern Africa have systematically cut down trees for firewood for thousands of years. The result has been that transpiration has decreased, decreasing rainfall and expanding the Sahara Desert. Similar deforestation is now occurring over much of Africa. The result is that the deserts of North, South and East Africa are expanding, leading to drought. Coupled with global warming induced changes in precipitation, it is likely that the peoples of much of Africa will be suffering from drought and starvation in the coming decades.
  • Africa's drought troubles began well before greenhouse gases increased to any appreciable degree. The inhabitants of Northern Africa have systematically cut down trees for firewood for thousands of years. The result has been that transpiration has decreased, decreasing rainfall and expanding the Sahara Desert. Similar deforestation is now occurring over much of Africa. The result is that the deserts of North, South and East Africa are expanding, leading to drought. Coupled with global warming induced changes in precipitation, it is likely that the peoples of much of Africa will be suffering from drought and starvation in the coming decades.
  • Africa's drought troubles began well before greenhouse gases increased to any appreciable degree. The inhabitants of Northern Africa have systematically cut down trees for firewood for thousands of years. The result has been that transpiration has decreased, decreasing rainfall and expanding the Sahara Desert. Similar deforestation is now occurring over much of Africa. The result is that the deserts of North, South and East Africa are expanding, leading to drought. Coupled with global warming induced changes in precipitation, it is likely that the peoples of much of Africa will be suffering from drought and starvation in the coming decades.
  • Africa's drought troubles began well before greenhouse gases increased to any appreciable degree. The inhabitants of Northern Africa have systematically cut down trees for firewood for thousands of years. The result has been that transpiration has decreased, decreasing rainfall and expanding the Sahara Desert. Similar deforestation is now occurring over much of Africa. The result is that the deserts of North, South and East Africa are expanding, leading to drought. Coupled with global warming induced changes in precipitation, it is likely that the peoples of much of Africa will be suffering from drought and starvation in the coming decades.
  • Africa's drought troubles began well before greenhouse gases increased to any appreciable degree. The inhabitants of Northern Africa have systematically cut down trees for firewood for thousands of years. The result has been that transpiration has decreased, decreasing rainfall and expanding the Sahara Desert. Similar deforestation is now occurring over much of Africa. The result is that the deserts of North, South and East Africa are expanding, leading to drought. Coupled with global warming induced changes in precipitation, it is likely that the peoples of much of Africa will be suffering from drought and starvation in the coming decades.
  • Africa's drought troubles began well before greenhouse gases increased to any appreciable degree. The inhabitants of Northern Africa have systematically cut down trees for firewood for thousands of years. The result has been that transpiration has decreased, decreasing rainfall and expanding the Sahara Desert. Similar deforestation is now occurring over much of Africa. The result is that the deserts of North, South and East Africa are expanding, leading to drought. Coupled with global warming induced changes in precipitation, it is likely that the peoples of much of Africa will be suffering from drought and starvation in the coming decades.
  • Depending upon the scenario,  the cost to stabilize carbon dioxide concentrations will be expensive (from 200 times the U.S. annual budget) to very expensive (up to 900 times the U.S. annual budget). 
  • 
  • Methods of mitigating global warming include 
    Conservation 
    Reduce energy needs, such as electrical usage, petroleum usage, reduced packaging 
    Recycling, which uses less energy to produce products compared to 
    Another way to reduce carbon emissions is to use alternate energy sources, such as 
    Nuclear 
    Wind 
    Geothermal 
    Hydroelectric 
    Solar 
    Fusion? 
  • Methods of mitigating global warming include 
    Conservation 
    Reduce energy needs, such as electrical usage, petroleum usage, reduced packaging 
    Recycling, which uses less energy to produce products compared to 
    Another way to reduce carbon emissions is to use alternate energy sources, such as 
    Nuclear 
    Wind 
    Geothermal 
    Hydroelectric 
    Solar 
    Fusion? 
  • Methods of mitigating global warming include 
    Conservation 
    Reduce energy needs, such as electrical usage, petroleum usage, reduced packaging 
    Recycling, which uses less energy to produce products compared to 
    Another way to reduce carbon emissions is to use alternate energy sources, such as 
    Nuclear 
    Wind 
    Geothermal 
    Hydroelectric 
    Solar 
    Fusion? 
  • Methods of mitigating global warming include 
    Conservation 
    Reduce energy needs, such as electrical usage, petroleum usage, reduced packaging 
    Recycling, which uses less energy to produce products compared to 
    Another way to reduce carbon emissions is to use alternate energy sources, such as 
    Nuclear 
    Wind 
    Geothermal 
    Hydroelectric 
    Solar 
    Fusion? 
  • Methods of mitigating global warming include 
    Conservation 
    Reduce energy needs, such as electrical usage, petroleum usage, reduced packaging 
    Recycling, which uses less energy to produce products compared to 
    Another way to reduce carbon emissions is to use alternate energy sources, such as 
    Nuclear 
    Wind 
    Geothermal 
    Hydroelectric 
    Solar 
    Fusion? 
  • Methods of mitigating global warming include 
    Conservation 
    Reduce energy needs, such as electrical usage, petroleum usage, reduced packaging 
    Recycling, which uses less energy to produce products compared to 
    Another way to reduce carbon emissions is to use alternate energy sources, such as 
    Nuclear 
    Wind 
    Geothermal 
    Hydroelectric 
    Solar 
    Fusion? 
  • Methods of mitigating global warming include 
    Conservation 
    Reduce energy needs, such as electrical usage, petroleum usage, reduced packaging 
    Recycling, which uses less energy to produce products compared to 
    Another way to reduce carbon emissions is to use alternate energy sources, such as 
    Nuclear 
    Wind 
    Geothermal 
    Hydroelectric 
    Solar 
    Fusion? 
  • Methods of mitigating global warming include 
    Conservation 
    Reduce energy needs, such as electrical usage, petroleum usage, reduced packaging 
    Recycling, which uses less energy to produce products compared to 
    Another way to reduce carbon emissions is to use alternate energy sources, such as 
    Nuclear 
    Wind 
    Geothermal 
    Hydroelectric 
    Solar 
    Fusion? 
  • Methods of mitigating global warming include 
    Conservation 
    Reduce energy needs, such as electrical usage, petroleum usage, reduced packaging 
    Recycling, which uses less energy to produce products compared to 
    Another way to reduce carbon emissions is to use alternate energy sources, such as 
    Nuclear 
    Wind 
    Geothermal 
    Hydroelectric 
    Solar 
    Fusion? 
  • Methods of mitigating global warming include 
    Conservation 
    Reduce energy needs, such as electrical usage, petroleum usage, reduced packaging 
    Recycling, which uses less energy to produce products compared to 
    Another way to reduce carbon emissions is to use alternate energy sources, such as 
    Nuclear 
    Wind 
    Geothermal 
    Hydroelectric 
    Solar 
    Fusion? 
  • Methods of mitigating global warming include 
    Conservation 
    Reduce energy needs, such as electrical usage, petroleum usage, reduced packaging 
    Recycling, which uses less energy to produce products compared to 
    Another way to reduce carbon emissions is to use alternate energy sources, such as 
    Nuclear 
    Wind 
    Geothermal 
    Hydroelectric 
    Solar 
    Fusion? 
  • Methods of mitigating global warming include 
    Conservation 
    Reduce energy needs, such as electrical usage, petroleum usage, reduced packaging 
    Recycling, which uses less energy to produce products compared to 
    Another way to reduce carbon emissions is to use alternate energy sources, such as 
    Nuclear 
    Wind 
    Geothermal 
    Hydroelectric 
    Solar 
    Fusion? 
  • Methods of mitigating global warming include 
    Conservation 
    Reduce energy needs, such as electrical usage, petroleum usage, reduced packaging 
    Recycling, which uses less energy to produce products compared to 
    Another way to reduce carbon emissions is to use alternate energy sources, such as 
    Nuclear 
    Wind 
    Geothermal 
    Hydroelectric 
    Solar 
    Fusion? 
  • Methods of mitigating global warming include 
    Conservation 
    Reduce energy needs, such as electrical usage, petroleum usage, reduced packaging 
    Recycling, which uses less energy to produce products compared to 
    Another way to reduce carbon emissions is to use alternate energy sources, such as 
    Nuclear 
    Wind 
    Geothermal 
    Hydroelectric 
    Solar 
    Fusion? 
  • Methods of mitigating global warming include 
    Conservation 
    Reduce energy needs, such as electrical usage, petroleum usage, reduced packaging 
    Recycling, which uses less energy to produce products compared to 
    Another way to reduce carbon emissions is to use alternate energy sources, such as 
    Nuclear 
    Wind 
    Geothermal 
    Hydroelectric 
    Solar 
    Fusion? 
  • Methods of mitigating global warming include 
    Conservation 
    Reduce energy needs, such as electrical usage, petroleum usage, reduced packaging 
    Recycling, which uses less energy to produce products compared to 
    Another way to reduce carbon emissions is to use alternate energy sources, such as 
    Nuclear 
    Wind 
    Geothermal 
    Hydroelectric 
    Solar 
    Fusion? 
  • Methods of mitigating global warming include 
    Conservation 
    Reduce energy needs, such as electrical usage, petroleum usage, reduced packaging 
    Recycling, which uses less energy to produce products compared to 
    Another way to reduce carbon emissions is to use alternate energy sources, such as 
    Nuclear 
    Wind 
    Geothermal 
    Hydroelectric 
    Solar 
    Fusion? 
  • Methods of mitigating global warming include 
    Conservation 
    Reduce energy needs, such as electrical usage, petroleum usage, reduced packaging 
    Recycling, which uses less energy to produce products compared to 
    Another way to reduce carbon emissions is to use alternate energy sources, such as 
    Nuclear 
    Wind 
    Geothermal 
    Hydroelectric 
    Solar 
    Fusion? 
  • Methods of mitigating global warming include 
    Conservation 
    Reduce energy needs, such as electrical usage, petroleum usage, reduced packaging 
    Recycling, which uses less energy to produce products compared to 
    Another way to reduce carbon emissions is to use alternate energy sources, such as 
    Nuclear 
    Wind 
    Geothermal 
    Hydroelectric 
    Solar 
    Fusion? 
  • Methods of mitigating global warming include 
    Conservation 
    Reduce energy needs, such as electrical usage, petroleum usage, reduced packaging 
    Recycling, which uses less energy to produce products compared to 
    Another way to reduce carbon emissions is to use alternate energy sources, such as 
    Nuclear 
    Wind 
    Geothermal 
    Hydroelectric 
    Solar 
    Fusion? 
  • Methods of mitigating global warming include 
    Conservation 
    Reduce energy needs, such as electrical usage, petroleum usage, reduced packaging 
    Recycling, which uses less energy to produce products compared to 
    Another way to reduce carbon emissions is to use alternate energy sources, such as 
    Nuclear 
    Wind 
    Geothermal 
    Hydroelectric 
    Solar 
    Fusion? 
  • Methods of mitigating global warming include 
    Conservation 
    Reduce energy needs, such as electrical usage, petroleum usage, reduced packaging 
    Recycling, which uses less energy to produce products compared to 
    Another way to reduce carbon emissions is to use alternate energy sources, such as 
    Nuclear 
    Wind 
    Geothermal 
    Hydroelectric 
    Solar 
    Fusion? 
  • Another promising way to reduce global warming is to store carbon dioxide underground.  Carbon dioxide can be pumped into depleted oil and gas reservoirs.  In addition, carbon dioxide can be pumped into existing oil and gas deposits to enhance recovery. Another method is to pump carbon dioxide into deep saline formations  both offshore  and onshore.  Carbon dioxide can also be used to enhance methane recovery from coal beds. 
  • Another promising way to reduce global warming is to store carbon dioxide underground.  Carbon dioxide can be pumped into depleted oil and gas reservoirs.  In addition, carbon dioxide can be pumped into existing oil and gas deposits to enhance recovery. Another method is to pump carbon dioxide into deep saline formations  both offshore  and onshore.  Carbon dioxide can also be used to enhance methane recovery from coal beds. 
  • Another promising way to reduce global warming is to store carbon dioxide underground.  Carbon dioxide can be pumped into depleted oil and gas reservoirs.  In addition, carbon dioxide can be pumped into existing oil and gas deposits to enhance recovery. Another method is to pump carbon dioxide into deep saline formations  both offshore  and onshore.  Carbon dioxide can also be used to enhance methane recovery from coal beds. 
  • Another promising way to reduce global warming is to store carbon dioxide underground.  Carbon dioxide can be pumped into depleted oil and gas reservoirs.  In addition, carbon dioxide can be pumped into existing oil and gas deposits to enhance recovery. Another method is to pump carbon dioxide into deep saline formations  both offshore  and onshore.  Carbon dioxide can also be used to enhance methane recovery from coal beds. 
  • Another promising way to reduce global warming is to store carbon dioxide underground.  Carbon dioxide can be pumped into depleted oil and gas reservoirs.  In addition, carbon dioxide can be pumped into existing oil and gas deposits to enhance recovery. Another method is to pump carbon dioxide into deep saline formations  both offshore  and onshore.  Carbon dioxide can also be used to enhance methane recovery from coal beds. 
  • Another promising way to reduce global warming is to store carbon dioxide underground.  Carbon dioxide can be pumped into depleted oil and gas reservoirs.  In addition, carbon dioxide can be pumped into existing oil and gas deposits to enhance recovery. Another method is to pump carbon dioxide into deep saline formations  both offshore  and onshore.  Carbon dioxide can also be used to enhance methane recovery from coal beds. 
  • Another promising way to reduce global warming is to store carbon dioxide underground.  Carbon dioxide can be pumped into depleted oil and gas reservoirs.  In addition, carbon dioxide can be pumped into existing oil and gas deposits to enhance recovery. Another method is to pump carbon dioxide into deep saline formations  both offshore  and onshore.  Carbon dioxide can also be used to enhance methane recovery from coal beds. 
  • Another promising way to reduce global warming is to store carbon dioxide underground.  Carbon dioxide can be pumped into depleted oil and gas reservoirs.  In addition, carbon dioxide can be pumped into existing oil and gas deposits to enhance recovery. Another method is to pump carbon dioxide into deep saline formations  both offshore  and onshore.  Carbon dioxide can also be used to enhance methane recovery from coal beds. 
  • Another promising way to reduce global warming is to store carbon dioxide underground.  Carbon dioxide can be pumped into depleted oil and gas reservoirs.  In addition, carbon dioxide can be pumped into existing oil and gas deposits to enhance recovery. Another method is to pump carbon dioxide into deep saline formations  both offshore  and onshore.  Carbon dioxide can also be used to enhance methane recovery from coal beds. 
  • Another promising way to reduce global warming is to store carbon dioxide underground.  Carbon dioxide can be pumped into depleted oil and gas reservoirs.  In addition, carbon dioxide can be pumped into existing oil and gas deposits to enhance recovery. Another method is to pump carbon dioxide into deep saline formations  both offshore  and onshore.  Carbon dioxide can also be used to enhance methane recovery from coal beds. 
  • Another promising way to reduce global warming is to store carbon dioxide underground.  Carbon dioxide can be pumped into depleted oil and gas reservoirs.  In addition, carbon dioxide can be pumped into existing oil and gas deposits to enhance recovery. Another method is to pump carbon dioxide into deep saline formations  both offshore  and onshore.  Carbon dioxide can also be used to enhance methane recovery from coal beds. 
  • Another promising way to reduce global warming is to store carbon dioxide underground.  Carbon dioxide can be pumped into depleted oil and gas reservoirs.  In addition, carbon dioxide can be pumped into existing oil and gas deposits to enhance recovery. Another method is to pump carbon dioxide into deep saline formations  both offshore  and onshore.  Carbon dioxide can also be used to enhance methane recovery from coal beds. 
  • Another promising way to reduce global warming is to store carbon dioxide underground.  Carbon dioxide can be pumped into depleted oil and gas reservoirs.  In addition, carbon dioxide can be pumped into existing oil and gas deposits to enhance recovery. Another method is to pump carbon dioxide into deep saline formations  both offshore  and onshore.  Carbon dioxide can also be used to enhance methane recovery from coal beds. 
  • Another promising way to reduce global warming is to store carbon dioxide underground.  Carbon dioxide can be pumped into depleted oil and gas reservoirs.  In addition, carbon dioxide can be pumped into existing oil and gas deposits to enhance recovery. Another method is to pump carbon dioxide into deep saline formations  both offshore  and onshore.  Carbon dioxide can also be used to enhance methane recovery from coal beds. 
  • Another promising way to reduce global warming is to store carbon dioxide underground.  Carbon dioxide can be pumped into depleted oil and gas reservoirs.  In addition, carbon dioxide can be pumped into existing oil and gas deposits to enhance recovery. Another method is to pump carbon dioxide into deep saline formations  both offshore  and onshore.  Carbon dioxide can also be used to enhance methane recovery from coal beds. 
  • Another promising way to reduce global warming is to store carbon dioxide underground.  Carbon dioxide can be pumped into depleted oil and gas reservoirs.  In addition, carbon dioxide can be pumped into existing oil and gas deposits to enhance recovery. Another method is to pump carbon dioxide into deep saline formations  both offshore  and onshore.  Carbon dioxide can also be used to enhance methane recovery from coal beds. 
  • Another promising way to reduce global warming is to store carbon dioxide underground.  Carbon dioxide can be pumped into depleted oil and gas reservoirs.  In addition, carbon dioxide can be pumped into existing oil and gas deposits to enhance recovery. Another method is to pump carbon dioxide into deep saline formations  both offshore  and onshore.  Carbon dioxide can also be used to enhance methane recovery from coal beds. 
  • Another promising way to reduce global warming is to store carbon dioxide underground.  Carbon dioxide can be pumped into depleted oil and gas reservoirs.  In addition, carbon dioxide can be pumped into existing oil and gas deposits to enhance recovery. Another method is to pump carbon dioxide into deep saline formations  both offshore  and onshore.  Carbon dioxide can also be used to enhance methane recovery from coal beds. 
  • Another promising way to reduce global warming is to store carbon dioxide underground.  Carbon dioxide can be pumped into depleted oil and gas reservoirs.  In addition, carbon dioxide can be pumped into existing oil and gas deposits to enhance recovery. Another method is to pump carbon dioxide into deep saline formations  both offshore  and onshore.  Carbon dioxide can also be used to enhance methane recovery from coal beds. 
  • Another promising way to reduce global warming is to store carbon dioxide underground.  Carbon dioxide can be pumped into depleted oil and gas reservoirs.  In addition, carbon dioxide can be pumped into existing oil and gas deposits to enhance recovery. Another method is to pump carbon dioxide into deep saline formations  both offshore  and onshore.  Carbon dioxide can also be used to enhance methane recovery from coal beds. 
  • Another promising way to reduce global warming is to store carbon dioxide underground.  Carbon dioxide can be pumped into depleted oil and gas reservoirs.  In addition, carbon dioxide can be pumped into existing oil and gas deposits to enhance recovery. Another method is to pump carbon dioxide into deep saline formations  both offshore  and onshore.  Carbon dioxide can also be used to enhance methane recovery from coal beds. 
  • Another promising way to reduce global warming is to store carbon dioxide underground.  Carbon dioxide can be pumped into depleted oil and gas reservoirs.  In addition, carbon dioxide can be pumped into existing oil and gas deposits to enhance recovery. Another method is to pump carbon dioxide into deep saline formations  both offshore  and onshore.  Carbon dioxide can also be used to enhance methane recovery from coal beds. 
  • Another promising way to reduce global warming is to store carbon dioxide underground.  Carbon dioxide can be pumped into depleted oil and gas reservoirs.  In addition, carbon dioxide can be pumped into existing oil and gas deposits to enhance recovery. Another method is to pump carbon dioxide into deep saline formations  both offshore  and onshore.  Carbon dioxide can also be used to enhance methane recovery from coal beds. 
  • Another promising way to reduce global warming is to store carbon dioxide underground.  Carbon dioxide can be pumped into depleted oil and gas reservoirs.  In addition, carbon dioxide can be pumped into existing oil and gas deposits to enhance recovery. Another method is to pump carbon dioxide into deep saline formations  both offshore  and onshore.  Carbon dioxide can also be used to enhance methane recovery from coal beds. 
  • Another promising way to reduce global warming is to store carbon dioxide underground.  Carbon dioxide can be pumped into depleted oil and gas reservoirs.  In addition, carbon dioxide can be pumped into existing oil and gas deposits to enhance recovery. Another method is to pump carbon dioxide into deep saline formations  both offshore  and onshore.  Carbon dioxide can also be used to enhance methane recovery from coal beds. 
  • Another promising way to reduce global warming is to store carbon dioxide underground.  Carbon dioxide can be pumped into depleted oil and gas reservoirs.  In addition, carbon dioxide can be pumped into existing oil and gas deposits to enhance recovery. Another method is to pump carbon dioxide into deep saline formations  both offshore  and onshore.  Carbon dioxide can also be used to enhance methane recovery from coal beds. 
  • Another promising way to reduce global warming is to store carbon dioxide underground.  Carbon dioxide can be pumped into depleted oil and gas reservoirs.  In addition, carbon dioxide can be pumped into existing oil and gas deposits to enhance recovery. Another method is to pump carbon dioxide into deep saline formations  both offshore  and onshore.  Carbon dioxide can also be used to enhance methane recovery from coal beds. 
  • Another promising way to reduce global warming is to store carbon dioxide underground.  Carbon dioxide can be pumped into depleted oil and gas reservoirs.  In addition, carbon dioxide can be pumped into existing oil and gas deposits to enhance recovery. Another method is to pump carbon dioxide into deep saline formations  both offshore  and onshore.  Carbon dioxide can also be used to enhance methane recovery from coal beds. 
  • Another promising way to reduce global warming is to store carbon dioxide underground.  Carbon dioxide can be pumped into depleted oil and gas reservoirs.  In addition, carbon dioxide can be pumped into existing oil and gas deposits to enhance recovery. Another method is to pump carbon dioxide into deep saline formations  both offshore  and onshore.  Carbon dioxide can also be used to enhance methane recovery from coal beds. 
  • Another promising way to reduce global warming is to store carbon dioxide underground.  Carbon dioxide can be pumped into depleted oil and gas reservoirs.  In addition, carbon dioxide can be pumped into existing oil and gas deposits to enhance recovery. Another method is to pump carbon dioxide into deep saline formations  both offshore  and onshore.  Carbon dioxide can also be used to enhance methane recovery from coal beds. 
  • Another promising way to reduce global warming is to store carbon dioxide underground.  Carbon dioxide can be pumped into depleted oil and gas reservoirs.  In addition, carbon dioxide can be pumped into existing oil and gas deposits to enhance recovery. Another method is to pump carbon dioxide into deep saline formations  both offshore  and onshore.  Carbon dioxide can also be used to enhance methane recovery from coal beds. 
  • Another promising way to reduce global warming is to store carbon dioxide underground.  Carbon dioxide can be pumped into depleted oil and gas reservoirs.  In addition, carbon dioxide can be pumped into existing oil and gas deposits to enhance recovery. Another method is to pump carbon dioxide into deep saline formations  both offshore  and onshore.  Carbon dioxide can also be used to enhance methane recovery from coal beds. 
  • Another promising way to reduce global warming is to store carbon dioxide underground.  Carbon dioxide can be pumped into depleted oil and gas reservoirs.  In addition, carbon dioxide can be pumped into existing oil and gas deposits to enhance recovery. Another method is to pump carbon dioxide into deep saline formations  both offshore  and onshore.  Carbon dioxide can also be used to enhance methane recovery from coal beds. 
  • Another promising way to reduce global warming is to store carbon dioxide underground.  Carbon dioxide can be pumped into depleted oil and gas reservoirs.  In addition, carbon dioxide can be pumped into existing oil and gas deposits to enhance recovery. Another method is to pump carbon dioxide into deep saline formations  both offshore  and onshore.  Carbon dioxide can also be used to enhance methane recovery from coal beds. 
  • Another promising way to reduce global warming is to store carbon dioxide underground.  Carbon dioxide can be pumped into depleted oil and gas reservoirs.  In addition, carbon dioxide can be pumped into existing oil and gas deposits to enhance recovery. Another method is to pump carbon dioxide into deep saline formations  both offshore  and onshore.  Carbon dioxide can also be used to enhance methane recovery from coal beds. 
  • Another promising way to reduce global warming is to store carbon dioxide underground.  Carbon dioxide can be pumped into depleted oil and gas reservoirs.  In addition, carbon dioxide can be pumped into existing oil and gas deposits to enhance recovery. Another method is to pump carbon dioxide into deep saline formations  both offshore  and onshore.  Carbon dioxide can also be used to enhance methane recovery from coal beds. 
  • Another promising way to reduce global warming is to store carbon dioxide underground.  Carbon dioxide can be pumped into depleted oil and gas reservoirs.  In addition, carbon dioxide can be pumped into existing oil and gas deposits to enhance recovery. Another method is to pump carbon dioxide into deep saline formations  both offshore  and onshore.  Carbon dioxide can also be used to enhance methane recovery from coal beds. 
  • Another promising way to reduce global warming is to store carbon dioxide underground.  Carbon dioxide can be pumped into depleted oil and gas reservoirs.  In addition, carbon dioxide can be pumped into existing oil and gas deposits to enhance recovery. Another method is to pump carbon dioxide into deep saline formations  both offshore  and onshore.  Carbon dioxide can also be used to enhance methane recovery from coal beds. 
  • Another promising way to reduce global warming is to store carbon dioxide underground.  Carbon dioxide can be pumped into depleted oil and gas reservoirs.  In addition, carbon dioxide can be pumped into existing oil and gas deposits to enhance recovery. Another method is to pump carbon dioxide into deep saline formations  both offshore  and onshore.  Carbon dioxide can also be used to enhance methane recovery from coal beds. 
  • Another promising way to reduce global warming is to store carbon dioxide underground.  Carbon dioxide can be pumped into depleted oil and gas reservoirs.  In addition, carbon dioxide can be pumped into existing oil and gas deposits to enhance recovery. Another method is to pump carbon dioxide into deep saline formations  both offshore  and onshore.  Carbon dioxide can also be used to enhance methane recovery from coal beds. 
  • Another promising way to reduce global warming is to store carbon dioxide underground.  Carbon dioxide can be pumped into depleted oil and gas reservoirs.  In addition, carbon dioxide can be pumped into existing oil and gas deposits to enhance recovery. Another method is to pump carbon dioxide into deep saline formations  both offshore  and onshore.  Carbon dioxide can also be used to enhance methane recovery from coal beds. 
  • Another promising way to reduce global warming is to store carbon dioxide underground.  Carbon dioxide can be pumped into depleted oil and gas reservoirs.  In addition, carbon dioxide can be pumped into existing oil and gas deposits to enhance recovery. Another method is to pump carbon dioxide into deep saline formations  both offshore  and onshore.  Carbon dioxide can also be used to enhance methane recovery from coal beds. 
  • Another promising way to reduce global warming is to store carbon dioxide underground.  Carbon dioxide can be pumped into depleted oil and gas reservoirs.  In addition, carbon dioxide can be pumped into existing oil and gas deposits to enhance recovery. Another method is to pump carbon dioxide into deep saline formations  both offshore  and onshore.  Carbon dioxide can also be used to enhance methane recovery from coal beds. 
  • Another promising way to reduce global warming is to store carbon dioxide underground.  Carbon dioxide can be pumped into depleted oil and gas reservoirs.  In addition, carbon dioxide can be pumped into existing oil and gas deposits to enhance recovery. Another method is to pump carbon dioxide into deep saline formations  both offshore  and onshore.  Carbon dioxide can also be used to enhance methane recovery from coal beds. 
  • Another promising way to reduce global warming is to store carbon dioxide underground.  Carbon dioxide can be pumped into depleted oil and gas reservoirs.  In addition, carbon dioxide can be pumped into existing oil and gas deposits to enhance recovery. Another method is to pump carbon dioxide into deep saline formations  both offshore  and onshore.  Carbon dioxide can also be used to enhance methane recovery from coal beds. 
  • Another promising way to reduce global warming is to store carbon dioxide underground.  Carbon dioxide can be pumped into depleted oil and gas reservoirs.  In addition, carbon dioxide can be pumped into existing oil and gas deposits to enhance recovery. Another method is to pump carbon dioxide into deep saline formations  both offshore  and onshore.  Carbon dioxide can also be used to enhance methane recovery from coal beds. 
  • Another promising way to reduce global warming is to store carbon dioxide underground.  Carbon dioxide can be pumped into depleted oil and gas reservoirs.  In addition, carbon dioxide can be pumped into existing oil and gas deposits to enhance recovery. Another method is to pump carbon dioxide into deep saline formations  both offshore  and onshore.  Carbon dioxide can also be used to enhance methane recovery from coal beds. 
  • Another promising way to reduce global warming is to store carbon dioxide underground.  Carbon dioxide can be pumped into depleted oil and gas reservoirs.  In addition, carbon dioxide can be pumped into existing oil and gas deposits to enhance recovery. Another method is to pump carbon dioxide into deep saline formations  both offshore  and onshore.  Carbon dioxide can also be used to enhance methane recovery from coal beds. 
  • Another promising way to reduce global warming is to store carbon dioxide underground.  Carbon dioxide can be pumped into depleted oil and gas reservoirs.  In addition, carbon dioxide can be pumped into existing oil and gas deposits to enhance recovery. Another method is to pump carbon dioxide into deep saline formations  both offshore  and onshore.  Carbon dioxide can also be used to enhance methane recovery from coal beds. 
  • I would like to take a few minutes to go over some common global warming myths. 
  •  Here we have our usual global surface temperatures.  The orange curve represents solar irradiance – the amount of energy received from the Sun. As you can see, the Sun goes through cycles about every ten years. When the Sun’s output is lowest, temperatures tend to level out.    So, it’s not surprising that temperatures have been flat for several years as we have been in a very deep solar trough.  The concerning thing is that temperatures continue to increase even as solar output has been recently declining. If the leveling of temperatures is due to reduced solar output, we should expect temperatures to go up considerably as the Sun comes out of its solar minimum. It’s like Hugh says, “Wait a few years and see where the evidence leads.” 
  •  Here we have our usual global surface temperatures.  The orange curve represents solar irradiance – the amount of energy received from the Sun. As you can see, the Sun goes through cycles about every ten years. When the Sun’s output is lowest, temperatures tend to level out.    So, it’s not surprising that temperatures have been flat for several years as we have been in a very deep solar trough.  The concerning thing is that temperatures continue to increase even as solar output has been recently declining. If the leveling of temperatures is due to reduced solar output, we should expect temperatures to go up considerably as the Sun comes out of its solar minimum. It’s like Hugh says, “Wait a few years and see where the evidence leads.” 
  •  Here we have our usual global surface temperatures.  The orange curve represents solar irradiance – the amount of energy received from the Sun. As you can see, the Sun goes through cycles about every ten years. When the Sun’s output is lowest, temperatures tend to level out.    So, it’s not surprising that temperatures have been flat for several years as we have been in a very deep solar trough.  The concerning thing is that temperatures continue to increase even as solar output has been recently declining. If the leveling of temperatures is due to reduced solar output, we should expect temperatures to go up considerably as the Sun comes out of its solar minimum. It’s like Hugh says, “Wait a few years and see where the evidence leads.” 
  •  Here we have our usual global surface temperatures.  The orange curve represents solar irradiance – the amount of energy received from the Sun. As you can see, the Sun goes through cycles about every ten years. When the Sun’s output is lowest, temperatures tend to level out.    So, it’s not surprising that temperatures have been flat for several years as we have been in a very deep solar trough.  The concerning thing is that temperatures continue to increase even as solar output has been recently declining. If the leveling of temperatures is due to reduced solar output, we should expect temperatures to go up considerably as the Sun comes out of its solar minimum. It’s like Hugh says, “Wait a few years and see where the evidence leads.” 
  •  Here we have our usual global surface temperatures.  The orange curve represents solar irradiance – the amount of energy received from the Sun. As you can see, the Sun goes through cycles about every ten years. When the Sun’s output is lowest, temperatures tend to level out.    So, it’s not surprising that temperatures have been flat for several years as we have been in a very deep solar trough.  The concerning thing is that temperatures continue to increase even as solar output has been recently declining. If the leveling of temperatures is due to reduced solar output, we should expect temperatures to go up considerably as the Sun comes out of its solar minimum. It’s like Hugh says, “Wait a few years and see where the evidence leads.” 
  •  Here we have our usual global surface temperatures.  The orange curve represents solar irradiance – the amount of energy received from the Sun. As you can see, the Sun goes through cycles about every ten years. When the Sun’s output is lowest, temperatures tend to level out.    So, it’s not surprising that temperatures have been flat for several years as we have been in a very deep solar trough.  The concerning thing is that temperatures continue to increase even as solar output has been recently declining. If the leveling of temperatures is due to reduced solar output, we should expect temperatures to go up considerably as the Sun comes out of its solar minimum. It’s like Hugh says, “Wait a few years and see where the evidence leads.” 
  •  Here we have our usual global surface temperatures.  The orange curve represents solar irradiance – the amount of energy received from the Sun. As you can see, the Sun goes through cycles about every ten years. When the Sun’s output is lowest, temperatures tend to level out.    So, it’s not surprising that temperatures have been flat for several years as we have been in a very deep solar trough.  The concerning thing is that temperatures continue to increase even as solar output has been recently declining. If the leveling of temperatures is due to reduced solar output, we should expect temperatures to go up considerably as the Sun comes out of its solar minimum. It’s like Hugh says, “Wait a few years and see where the evidence leads.” 
  •  Here we have our usual global surface temperatures.  The orange curve represents solar irradiance – the amount of energy received from the Sun. As you can see, the Sun goes through cycles about every ten years. When the Sun’s output is lowest, temperatures tend to level out.    So, it’s not surprising that temperatures have been flat for several years as we have been in a very deep solar trough.  The concerning thing is that temperatures continue to increase even as solar output has been recently declining. If the leveling of temperatures is due to reduced solar output, we should expect temperatures to go up considerably as the Sun comes out of its solar minimum. It’s like Hugh says, “Wait a few years and see where the evidence leads.” 
  •  Here we have our usual global surface temperatures.  The orange curve represents solar irradiance – the amount of energy received from the Sun. As you can see, the Sun goes through cycles about every ten years. When the Sun’s output is lowest, temperatures tend to level out.    So, it’s not surprising that temperatures have been flat for several years as we have been in a very deep solar trough.  The concerning thing is that temperatures continue to increase even as solar output has been recently declining. If the leveling of temperatures is due to reduced solar output, we should expect temperatures to go up considerably as the Sun comes out of its solar minimum. It’s like Hugh says, “Wait a few years and see where the evidence leads.” 
  •  Here we have our usual global surface temperatures.  The orange curve represents solar irradiance – the amount of energy received from the Sun. As you can see, the Sun goes through cycles about every ten years. When the Sun’s output is lowest, temperatures tend to level out.    So, it’s not surprising that temperatures have been flat for several years as we have been in a very deep solar trough.  The concerning thing is that temperatures continue to increase even as solar output has been recently declining. If the leveling of temperatures is due to reduced solar output, we should expect temperatures to go up considerably as the Sun comes out of its solar minimum. It’s like Hugh says, “Wait a few years and see where the evidence leads.” 
  •  Here we have our usual global surface temperatures.  The orange curve represents solar irradiance – the amount of energy received from the Sun. As you can see, the Sun goes through cycles about every ten years. When the Sun’s output is lowest, temperatures tend to level out.    So, it’s not surprising that temperatures have been flat for several years as we have been in a very deep solar trough.  The concerning thing is that temperatures continue to increase even as solar output has been recently declining. If the leveling of temperatures is due to reduced solar output, we should expect temperatures to go up considerably as the Sun comes out of its solar minimum. It’s like Hugh says, “Wait a few years and see where the evidence leads.” 
  •  Here we have our usual global surface temperatures.  The orange curve represents solar irradiance – the amount of energy received from the Sun. As you can see, the Sun goes through cycles about every ten years. When the Sun’s output is lowest, temperatures tend to level out.    So, it’s not surprising that temperatures have been flat for several years as we have been in a very deep solar trough.  The concerning thing is that temperatures continue to increase even as solar output has been recently declining. If the leveling of temperatures is due to reduced solar output, we should expect temperatures to go up considerably as the Sun comes out of its solar minimum. It’s like Hugh says, “Wait a few years and see where the evidence leads.” 
  •  Here we have our usual global surface temperatures.  The orange curve represents solar irradiance – the amount of energy received from the Sun. As you can see, the Sun goes through cycles about every ten years. When the Sun’s output is lowest, temperatures tend to level out.    So, it’s not surprising that temperatures have been flat for several years as we have been in a very deep solar trough.  The concerning thing is that temperatures continue to increase even as solar output has been recently declining. If the leveling of temperatures is due to reduced solar output, we should expect temperatures to go up considerably as the Sun comes out of its solar minimum. It’s like Hugh says, “Wait a few years and see where the evidence leads.” 
  •  Here we have our usual global surface temperatures.  The orange curve represents solar irradiance – the amount of energy received from the Sun. As you can see, the Sun goes through cycles about every ten years. When the Sun’s output is lowest, temperatures tend to level out.    So, it’s not surprising that temperatures have been flat for several years as we have been in a very deep solar trough.  The concerning thing is that temperatures continue to increase even as solar output has been recently declining. If the leveling of temperatures is due to reduced solar output, we should expect temperatures to go up considerably as the Sun comes out of its solar minimum. It’s like Hugh says, “Wait a few years and see where the evidence leads.” 
  •  Here we have our usual global surface temperatures.  The orange curve represents solar irradiance – the amount of energy received from the Sun. As you can see, the Sun goes through cycles about every ten years. When the Sun’s output is lowest, temperatures tend to level out.    So, it’s not surprising that temperatures have been flat for several years as we have been in a very deep solar trough.  The concerning thing is that temperatures continue to increase even as solar output has been recently declining. If the leveling of temperatures is due to reduced solar output, we should expect temperatures to go up considerably as the Sun comes out of its solar minimum. It’s like Hugh says, “Wait a few years and see where the evidence leads.” 
  • Another myth is that volcanoes emit more carbon dioxide than fossil fuel burning.  Here we see the amount of carbon from volcanoes  compared with the amount from fossil fuels. It isn’t even close!. 
  • Another myth is that volcanoes emit more carbon dioxide than fossil fuel burning.  Here we see the amount of carbon from volcanoes  compared with the amount from fossil fuels. It isn’t even close!. 
  • Another myth is that global warming is caused by sunspots.  Here we have our usual global temperature plot,  which we can compare to sunspot activity  We can see that there is no correlation between the two curves. 
  • Another myth is that global warming is caused by sunspots.  Here we have our usual global temperature plot,  which we can compare to sunspot activity  We can see that there is no correlation between the two curves. 
  • Another myth is that global warming is caused by sunspots.  Here we have our usual global temperature plot,  which we can compare to sunspot activity  We can see that there is no correlation between the two curves. 
  • Another myth is that global warming is caused by sunspots.  Here we have our usual global temperature plot,  which we can compare to sunspot activity  We can see that there is no correlation between the two curves. 
  • Another myth is that global warming is caused by sunspots.  Here we have our usual global temperature plot,  which we can compare to sunspot activity  We can see that there is no correlation between the two curves. 
  • Another myth is that global warming is caused by sunspots.  Here we have our usual global temperature plot,  which we can compare to sunspot activity  We can see that there is no correlation between the two curves. 
  • We actually have sunspot data from the 18th century. Here the temperature data from Hadley, UK  is plotted compared with the number of sunspots  Again, there isn’t any correlation. 
  • We actually have sunspot data from the 18th century. Here the temperature data from Hadley, UK  is plotted compared with the number of sunspots  Again, there isn’t any correlation. 
  • We actually have sunspot data from the 18th century. Here the temperature data from Hadley, UK  is plotted compared with the number of sunspots  Again, there isn’t any correlation. 
  • We actually have sunspot data from the 18th century. Here the temperature data from Hadley, UK  is plotted compared with the number of sunspots  Again, there isn’t any correlation. 
  • We actually have sunspot data from the 18th century. Here the temperature data from Hadley, UK  is plotted compared with the number of sunspots  Again, there isn’t any correlation. 
  • We actually have sunspot data from the 18th century. Here the temperature data from Hadley, UK  is plotted compared with the number of sunspots  Again, there isn’t any correlation. 
  • Another myth is that global warming is caused by gamma cosmic rays Here is a plot of global temperatures over the last 60 years  When plotted against Gamma Cosmic Rays,  one can see that there is no correlation. 
  • Another myth is that global warming is caused by gamma cosmic rays Here is a plot of global temperatures over the last 60 years  When plotted against Gamma Cosmic Rays,  one can see that there is no correlation. 
  • Another myth is that global warming is caused by gamma cosmic rays Here is a plot of global temperatures over the last 60 years  When plotted against Gamma Cosmic Rays,  one can see that there is no correlation. 
  • Another myth is that global warming is caused by gamma cosmic rays Here is a plot of global temperatures over the last 60 years  When plotted against Gamma Cosmic Rays,  one can see that there is no correlation. 
  • Another myth is that global warming is caused by gamma cosmic rays Here is a plot of global temperatures over the last 60 years  When plotted against Gamma Cosmic Rays,  one can see that there is no correlation. 
  • Skeptics say there is no correlation between carbon dioxide levels and temperatures. However, if we compare  carbon dioxide with  sea surface temperatures for the last five glacial cycles, we find that there is a high coincidence of carbon dioxide levels and temperatures in the past. In addition,  there is a high correlation between carbon dioxide and sea levels
  • Skeptics say there is no correlation between carbon dioxide levels and temperatures. However, if we compare  carbon dioxide with  sea surface temperatures for the last five glacial cycles, we find that there is a high coincidence of carbon dioxide levels and temperatures in the past. In addition,  there is a high correlation between carbon dioxide and sea levels
  • Skeptics say there is no correlation between carbon dioxide levels and temperatures. However, if we compare  carbon dioxide with  sea surface temperatures for the last five glacial cycles, we find that there is a high coincidence of carbon dioxide levels and temperatures in the past. In addition,  there is a high correlation between carbon dioxide and sea levels
  • Skeptics say there is no correlation between carbon dioxide levels and temperatures. However, if we compare  carbon dioxide with  sea surface temperatures for the last five glacial cycles, we find that there is a high coincidence of carbon dioxide levels and temperatures in the past. In addition,  there is a high correlation between carbon dioxide and sea levels
  • Skeptics say there is no correlation between carbon dioxide levels and temperatures. However, if we compare  carbon dioxide with  sea surface temperatures for the last five glacial cycles, we find that there is a high coincidence of carbon dioxide levels and temperatures in the past. In addition,  there is a high correlation between carbon dioxide and sea levels
  • Skeptics say there is no correlation between carbon dioxide levels and temperatures. However, if we compare  carbon dioxide with  sea surface temperatures for the last five glacial cycles, we find that there is a high coincidence of carbon dioxide levels and temperatures in the past. In addition,  there is a high correlation between carbon dioxide and sea levels
  • Is global warming due to heat island effects? Heat island effects occur when a temperature station gets surrounded by buildings and streets, artificially raising the temperature readings. Here we see a plot of global temperature changes (higher in red and lower in blue) for 2009 compared with 1951-1980  What we notice here is that nearly all of the dramatic temperature increases have occurred in the far northern latitudes, where we would be hard pressed to find numerous cities where heat island effects would be expected to be found. 
  • Mount Kilimanjaro is the poster child of the global warming movement,  since most of the glacier has disappeared  over the last 30 years. However experts agree that the shrinking of the Mount Kilimanjaro glacier is more the result of deforestation of the surrounding area rather than changes due to global warming, since temperatures in the area have not appreciably climbed in recent years. 
  • Mount Kilimanjaro is the poster child of the global warming movement,  since most of the glacier has disappeared  over the last 30 years. However experts agree that the shrinking of the Mount Kilimanjaro glacier is more the result of deforestation of the surrounding area rather than changes due to global warming, since temperatures in the area have not appreciably climbed in recent years. 
  • Is global warming truly global? If we examine global warming from the perspective of the two hemispheres, we find that  temperatures in the northern hemisphere have increased much more than  temperatures in the southern hemisphere. In a similar fashion,  temperatures over land masses have increased much more than  temperatures over the oceans. This is because the oceans tend to moderate temperature changes. So, since two thirds of the earth’s land mass is in the northern hemisphere, we would expect global warming to have its largest impact there. 
  • Is global warming truly global? If we examine global warming from the perspective of the two hemispheres, we find that  temperatures in the northern hemisphere have increased much more than  temperatures in the southern hemisphere. In a similar fashion,  temperatures over land masses have increased much more than  temperatures over the oceans. This is because the oceans tend to moderate temperature changes. So, since two thirds of the earth’s land mass is in the northern hemisphere, we would expect global warming to have its largest impact there. 
  • Is global warming truly global? If we examine global warming from the perspective of the two hemispheres, we find that  temperatures in the northern hemisphere have increased much more than  temperatures in the southern hemisphere. In a similar fashion,  temperatures over land masses have increased much more than  temperatures over the oceans. This is because the oceans tend to moderate temperature changes. So, since two thirds of the earth’s land mass is in the northern hemisphere, we would expect global warming to have its largest impact there. 
  • Is global warming truly global? If we examine global warming from the perspective of the two hemispheres, we find that  temperatures in the northern hemisphere have increased much more than  temperatures in the southern hemisphere. In a similar fashion,  temperatures over land masses have increased much more than  temperatures over the oceans. This is because the oceans tend to moderate temperature changes. So, since two thirds of the earth’s land mass is in the northern hemisphere, we would expect global warming to have its largest impact there. 
  • Is global warming truly global? If we examine global warming from the perspective of the two hemispheres, we find that  temperatures in the northern hemisphere have increased much more than  temperatures in the southern hemisphere. In a similar fashion,  temperatures over land masses have increased much more than  temperatures over the oceans. This is because the oceans tend to moderate temperature changes. So, since two thirds of the earth’s land mass is in the northern hemisphere, we would expect global warming to have its largest impact there. 
  • Is global warming truly global? If we examine global warming from the perspective of the two hemispheres, we find that  temperatures in the northern hemisphere have increased much more than  temperatures in the southern hemisphere. In a similar fashion,  temperatures over land masses have increased much more than  temperatures over the oceans. This is because the oceans tend to moderate temperature changes. So, since two thirds of the earth’s land mass is in the northern hemisphere, we would expect global warming to have its largest impact there. 
  • Is global warming truly global? If we examine global warming from the perspective of the two hemispheres, we find that  temperatures in the northern hemisphere have increased much more than  temperatures in the southern hemisphere. In a similar fashion,  temperatures over land masses have increased much more than  temperatures over the oceans. This is because the oceans tend to moderate temperature changes. So, since two thirds of the earth’s land mass is in the northern hemisphere, we would expect global warming to have its largest impact there. 
  • Is global warming truly global? If we examine global warming from the perspective of the two hemispheres, we find that  temperatures in the northern hemisphere have increased much more than  temperatures in the southern hemisphere. In a similar fashion,  temperatures over land masses have increased much more than  temperatures over the oceans. This is because the oceans tend to moderate temperature changes. So, since two thirds of the earth’s land mass is in the northern hemisphere, we would expect global warming to have its largest impact there. 
  • Is global warming truly global? If we examine global warming from the perspective of the two hemispheres, we find that  temperatures in the northern hemisphere have increased much more than  temperatures in the southern hemisphere. In a similar fashion,  temperatures over land masses have increased much more than  temperatures over the oceans. This is because the oceans tend to moderate temperature changes. So, since two thirds of the earth’s land mass is in the northern hemisphere, we would expect global warming to have its largest impact there. 
  • Is global warming truly global? If we examine global warming from the perspective of the two hemispheres, we find that  temperatures in the northern hemisphere have increased much more than  temperatures in the southern hemisphere. In a similar fashion,  temperatures over land masses have increased much more than  temperatures over the oceans. This is because the oceans tend to moderate temperature changes. So, since two thirds of the earth’s land mass is in the northern hemisphere, we would expect global warming to have its largest impact there. 
  • Is global warming truly global? If we examine global warming from the perspective of the two hemispheres, we find that  temperatures in the northern hemisphere have increased much more than  temperatures in the southern hemisphere. In a similar fashion,  temperatures over land masses have increased much more than  temperatures over the oceans. This is because the oceans tend to moderate temperature changes. So, since two thirds of the earth’s land mass is in the northern hemisphere, we would expect global warming to have its largest impact there. 
  • Is global warming truly global? If we examine global warming from the perspective of the two hemispheres, we find that  temperatures in the northern hemisphere have increased much more than  temperatures in the southern hemisphere. In a similar fashion,  temperatures over land masses have increased much more than  temperatures over the oceans. This is because the oceans tend to moderate temperature changes. So, since two thirds of the earth’s land mass is in the northern hemisphere, we would expect global warming to have its largest impact there. 
  • Is global warming truly global? If we examine global warming from the perspective of the two hemispheres, we find that  temperatures in the northern hemisphere have increased much more than  temperatures in the southern hemisphere. In a similar fashion,  temperatures over land masses have increased much more than  temperatures over the oceans. This is because the oceans tend to moderate temperature changes. So, since two thirds of the earth’s land mass is in the northern hemisphere, we would expect global warming to have its largest impact there. 
  • Are sea levels going to rise 5 to 6 feet this century? 
    The present measured rate is 1.8 mm/yr, which is equivalent to 7.4 in/century 
    Another study indicates that this rate is accelerating at 13 thousandths of a mm per year per year 
    If this acceleration continues, this could result in a 12 inch sea level rise in this century 
    Scenarios claiming a 1 meter or more rise in sea levels are unrealistic.  The California State Lands Commission recently claimed that sea levels could rise 55 inches this century, inundating ports in the state. And you wonder why we have a budget crisis.
  • Are sea levels going to rise 5 to 6 feet this century? 
    The present measured rate is 1.8 mm/yr, which is equivalent to 7.4 in/century 
    Another study indicates that this rate is accelerating at 13 thousandths of a mm per year per year 
    If this acceleration continues, this could result in a 12 inch sea level rise in this century 
    Scenarios claiming a 1 meter or more rise in sea levels are unrealistic.  The California State Lands Commission recently claimed that sea levels could rise 55 inches this century, inundating ports in the state. And you wonder why we have a budget crisis.
  • Are sea levels going to rise 5 to 6 feet this century? 
    The present measured rate is 1.8 mm/yr, which is equivalent to 7.4 in/century 
    Another study indicates that this rate is accelerating at 13 thousandths of a mm per year per year 
    If this acceleration continues, this could result in a 12 inch sea level rise in this century 
    Scenarios claiming a 1 meter or more rise in sea levels are unrealistic.  The California State Lands Commission recently claimed that sea levels could rise 55 inches this century, inundating ports in the state. And you wonder why we have a budget crisis.
  • Are sea levels going to rise 5 to 6 feet this century? 
    The present measured rate is 1.8 mm/yr, which is equivalent to 7.4 in/century 
    Another study indicates that this rate is accelerating at 13 thousandths of a mm per year per year 
    If this acceleration continues, this could result in a 12 inch sea level rise in this century 
    Scenarios claiming a 1 meter or more rise in sea levels are unrealistic.  The California State Lands Commission recently claimed that sea levels could rise 55 inches this century, inundating ports in the state. And you wonder why we have a budget crisis.
  • Are sea levels going to rise 5 to 6 feet this century? 
    The present measured rate is 1.8 mm/yr, which is equivalent to 7.4 in/century 
    Another study indicates that this rate is accelerating at 13 thousandths of a mm per year per year 
    If this acceleration continues, this could result in a 12 inch sea level rise in this century 
    Scenarios claiming a 1 meter or more rise in sea levels are unrealistic.  The California State Lands Commission recently claimed that sea levels could rise 55 inches this century, inundating ports in the state. And you wonder why we have a budget crisis.
  • Measurement of sea levels have been carried out for three European ports over the last few hundred years. The results can be seen for a  port in the Netherlands,  one in France,  and one in Poland.  When the sea level is compared to recorded temperatures over this period of time, the correlation is quite good. However, we are talking about only a 7 inch rise in sea levels over the last century. 
  • Measurement of sea levels have been carried out for three European ports over the last few hundred years. The results can be seen for a  port in the Netherlands,  one in France,  and one in Poland.  When the sea level is compared to recorded temperatures over this period of time, the correlation is quite good. However, we are talking about only a 7 inch rise in sea levels over the last century. 
  • Measurement of sea levels have been carried out for three European ports over the last few hundred years. The results can be seen for a  port in the Netherlands,  one in France,  and one in Poland.  When the sea level is compared to recorded temperatures over this period of time, the correlation is quite good. However, we are talking about only a 7 inch rise in sea levels over the last century. 
  • Measurement of sea levels have been carried out for three European ports over the last few hundred years. The results can be seen for a  port in the Netherlands,  one in France,  and one in Poland.  When the sea level is compared to recorded temperatures over this period of time, the correlation is quite good. However, we are talking about only a 7 inch rise in sea levels over the last century. 
  • Measurement of sea levels have been carried out for three European ports over the last few hundred years. The results can be seen for a  port in the Netherlands,  one in France,  and one in Poland.  When the sea level is compared to recorded temperatures over this period of time, the correlation is quite good. However, we are talking about only a 7 inch rise in sea levels over the last century. 
  • Measurement of sea levels have been carried out for three European ports over the last few hundred years. The results can be seen for a  port in the Netherlands,  one in France,  and one in Poland.  When the sea level is compared to recorded temperatures over this period of time, the correlation is quite good. However, we are talking about only a 7 inch rise in sea levels over the last century. 
  • How much will temperatures increase in the future? 
    Some models propose up to 9°C increase this century 
    Two studies put the minimum at 1.5°C and maximum at 4.5°C or 6.2°C 
    Another study puts the minimum at 2.5°C What about previously predicted increases? 
  • How much will temperatures increase in the future? 
    Some models propose up to 9°C increase this century 
    Two studies put the minimum at 1.5°C and maximum at 4.5°C or 6.2°C 
    Another study puts the minimum at 2.5°C What about previously predicted increases? 
  • How much will temperatures increase in the future? 
    Some models propose up to 9°C increase this century 
    Two studies put the minimum at 1.5°C and maximum at 4.5°C or 6.2°C 
    Another study puts the minimum at 2.5°C What about previously predicted increases? 
  •  In 1988 Jim Hansen published a study that modeled global temperatures as a function of carbon emissions. The graph, shown here,  and cleaned up from the original journal scan, shows Hansen’s computer models for temperature as a function of carbon emissions.  The white solid line indicates observed temperatures through 1988, when the study was published.  The orange dotted line is a computer model of temperatures assuming carbon emissions continued to be produced exponentially  The blue dashed line assumed carbon emissions would be moderately curtailed,  And the yellow dotted line assumed carbon emissions would be drastically curtailed. What does the actual data look like?  It almost exactly follows the drastic reduction projection, even though carbon emiisions have basically gone unchecked since 1988. So, past predictions have tended to overestimate the increase in global temperatures. 
  •  In 1988 Jim Hansen published a study that modeled global temperatures as a function of carbon emissions. The graph, shown here,  and cleaned up from the original journal scan, shows Hansen’s computer models for temperature as a function of carbon emissions.  The white solid line indicates observed temperatures through 1988, when the study was published.  The orange dotted line is a computer model of temperatures assuming carbon emissions continued to be produced exponentially  The blue dashed line assumed carbon emissions would be moderately curtailed,  And the yellow dotted line assumed carbon emissions would be drastically curtailed. What does the actual data look like?  It almost exactly follows the drastic reduction projection, even though carbon emiisions have basically gone unchecked since 1988. So, past predictions have tended to overestimate the increase in global temperatures. 
  •  In 1988 Jim Hansen published a study that modeled global temperatures as a function of carbon emissions. The graph, shown here,  and cleaned up from the original journal scan, shows Hansen’s computer models for temperature as a function of carbon emissions.  The white solid line indicates observed temperatures through 1988, when the study was published.  The orange dotted line is a computer model of temperatures assuming carbon emissions continued to be produced exponentially  The blue dashed line assumed carbon emissions would be moderately curtailed,  And the yellow dotted line assumed carbon emissions would be drastically curtailed. What does the actual data look like?  It almost exactly follows the drastic reduction projection, even though carbon emiisions have basically gone unchecked since 1988. So, past predictions have tended to overestimate the increase in global temperatures. 
  •  In 1988 Jim Hansen published a study that modeled global temperatures as a function of carbon emissions. The graph, shown here,  and cleaned up from the original journal scan, shows Hansen’s computer models for temperature as a function of carbon emissions.  The white solid line indicates observed temperatures through 1988, when the study was published.  The orange dotted line is a computer model of temperatures assuming carbon emissions continued to be produced exponentially  The blue dashed line assumed carbon emissions would be moderately curtailed,  And the yellow dotted line assumed carbon emissions would be drastically curtailed. What does the actual data look like?  It almost exactly follows the drastic reduction projection, even though carbon emiisions have basically gone unchecked since 1988. So, past predictions have tended to overestimate the increase in global temperatures. 
  •  In 1988 Jim Hansen published a study that modeled global temperatures as a function of carbon emissions. The graph, shown here,  and cleaned up from the original journal scan, shows Hansen’s computer models for temperature as a function of carbon emissions.  The white solid line indicates observed temperatures through 1988, when the study was published.  The orange dotted line is a computer model of temperatures assuming carbon emissions continued to be produced exponentially  The blue dashed line assumed carbon emissions would be moderately curtailed,  And the yellow dotted line assumed carbon emissions would be drastically curtailed. What does the actual data look like?  It almost exactly follows the drastic reduction projection, even though carbon emiisions have basically gone unchecked since 1988. So, past predictions have tended to overestimate the increase in global temperatures. 
  •  In 1988 Jim Hansen published a study that modeled global temperatures as a function of carbon emissions. The graph, shown here,  and cleaned up from the original journal scan, shows Hansen’s computer models for temperature as a function of carbon emissions.  The white solid line indicates observed temperatures through 1988, when the study was published.  The orange dotted line is a computer model of temperatures assuming carbon emissions continued to be produced exponentially  The blue dashed line assumed carbon emissions would be moderately curtailed,  And the yellow dotted line assumed carbon emissions would be drastically curtailed. What does the actual data look like?  It almost exactly follows the drastic reduction projection, even though carbon emiisions have basically gone unchecked since 1988. So, past predictions have tended to overestimate the increase in global temperatures. 
  •  In 1988 Jim Hansen published a study that modeled global temperatures as a function of carbon emissions. The graph, shown here,  and cleaned up from the original journal scan, shows Hansen’s computer models for temperature as a function of carbon emissions.  The white solid line indicates observed temperatures through 1988, when the study was published.  The orange dotted line is a computer model of temperatures assuming carbon emissions continued to be produced exponentially  The blue dashed line assumed carbon emissions would be moderately curtailed,  And the yellow dotted line assumed carbon emissions would be drastically curtailed. What does the actual data look like?  It almost exactly follows the drastic reduction projection, even though carbon emiisions have basically gone unchecked since 1988. So, past predictions have tended to overestimate the increase in global temperatures. 
  •  In 1988 Jim Hansen published a study that modeled global temperatures as a function of carbon emissions. The graph, shown here,  and cleaned up from the original journal scan, shows Hansen’s computer models for temperature as a function of carbon emissions.  The white solid line indicates observed temperatures through 1988, when the study was published.  The orange dotted line is a computer model of temperatures assuming carbon emissions continued to be produced exponentially  The blue dashed line assumed carbon emissions would be moderately curtailed,  And the yellow dotted line assumed carbon emissions would be drastically curtailed. What does the actual data look like?  It almost exactly follows the drastic reduction projection, even though carbon emiisions have basically gone unchecked since 1988. So, past predictions have tended to overestimate the increase in global temperatures. 
  •  In 1988 Jim Hansen published a study that modeled global temperatures as a function of carbon emissions. The graph, shown here,  and cleaned up from the original journal scan, shows Hansen’s computer models for temperature as a function of carbon emissions.  The white solid line indicates observed temperatures through 1988, when the study was published.  The orange dotted line is a computer model of temperatures assuming carbon emissions continued to be produced exponentially  The blue dashed line assumed carbon emissions would be moderately curtailed,  And the yellow dotted line assumed carbon emissions would be drastically curtailed. What does the actual data look like?  It almost exactly follows the drastic reduction projection, even though carbon emiisions have basically gone unchecked since 1988. So, past predictions have tended to overestimate the increase in global temperatures. 
  •  In 1988 Jim Hansen published a study that modeled global temperatures as a function of carbon emissions. The graph, shown here,  and cleaned up from the original journal scan, shows Hansen’s computer models for temperature as a function of carbon emissions.  The white solid line indicates observed temperatures through 1988, when the study was published.  The orange dotted line is a computer model of temperatures assuming carbon emissions continued to be produced exponentially  The blue dashed line assumed carbon emissions would be moderately curtailed,  And the yellow dotted line assumed carbon emissions would be drastically curtailed. What does the actual data look like?  It almost exactly follows the drastic reduction projection, even though carbon emiisions have basically gone unchecked since 1988. So, past predictions have tended to overestimate the increase in global temperatures. 
  •  In 1988 Jim Hansen published a study that modeled global temperatures as a function of carbon emissions. The graph, shown here,  and cleaned up from the original journal scan, shows Hansen’s computer models for temperature as a function of carbon emissions.  The white solid line indicates observed temperatures through 1988, when the study was published.  The orange dotted line is a computer model of temperatures assuming carbon emissions continued to be produced exponentially  The blue dashed line assumed carbon emissions would be moderately curtailed,  And the yellow dotted line assumed carbon emissions would be drastically curtailed. What does the actual data look like?  It almost exactly follows the drastic reduction projection, even though carbon emiisions have basically gone unchecked since 1988. So, past predictions have tended to overestimate the increase in global temperatures. 
  •  In 1988 Jim Hansen published a study that modeled global temperatures as a function of carbon emissions. The graph, shown here,  and cleaned up from the original journal scan, shows Hansen’s computer models for temperature as a function of carbon emissions.  The white solid line indicates observed temperatures through 1988, when the study was published.  The orange dotted line is a computer model of temperatures assuming carbon emissions continued to be produced exponentially  The blue dashed line assumed carbon emissions would be moderately curtailed,  And the yellow dotted line assumed carbon emissions would be drastically curtailed. What does the actual data look like?  It almost exactly follows the drastic reduction projection, even though carbon emiisions have basically gone unchecked since 1988. So, past predictions have tended to overestimate the increase in global temperatures. 
  •  In 1988 Jim Hansen published a study that modeled global temperatures as a function of carbon emissions. The graph, shown here,  and cleaned up from the original journal scan, shows Hansen’s computer models for temperature as a function of carbon emissions.  The white solid line indicates observed temperatures through 1988, when the study was published.  The orange dotted line is a computer model of temperatures assuming carbon emissions continued to be produced exponentially  The blue dashed line assumed carbon emissions would be moderately curtailed,  And the yellow dotted line assumed carbon emissions would be drastically curtailed. What does the actual data look like?  It almost exactly follows the drastic reduction projection, even though carbon emiisions have basically gone unchecked since 1988. So, past predictions have tended to overestimate the increase in global temperatures. 
  •  This is our usual plot of temperature over time on a scale that extends to the end of the century.  If we extrapolate the line, we get a 2.5 degree temperature increase. However, this assumes that the rate of increase stays constant. Given the past temperature history, it seems likely that temperatures will go through periods of little or no increase, suggesting that the overall temperature increase will be less than 2.5 degrees. If there are positive feedbacks, it is possible that temperatures will move up more quickly. However, even a 2.5 degree centigrade increase is nothing to take lightly. My advice, let’s see what happens in the next ten years as the Sun goes through its solar maximum. It temperatures begin to rise again, I think we have reason to be concerned. If the last 100 year’s increases are part of some natural climate variation, temperatures should level off soon. Time will tell. 
  •  This is our usual plot of temperature over time on a scale that extends to the end of the century.  If we extrapolate the line, we get a 2.5 degree temperature increase. However, this assumes that the rate of increase stays constant. Given the past temperature history, it seems likely that temperatures will go through periods of little or no increase, suggesting that the overall temperature increase will be less than 2.5 degrees. If there are positive feedbacks, it is possible that temperatures will move up more quickly. However, even a 2.5 degree centigrade increase is nothing to take lightly. My advice, let’s see what happens in the next ten years as the Sun goes through its solar maximum. It temperatures begin to rise again, I think we have reason to be concerned. If the last 100 year’s increases are part of some natural climate variation, temperatures should level off soon. Time will tell. 
  •  This is our usual plot of temperature over time on a scale that extends to the end of the century.  If we extrapolate the line, we get a 2.5 degree temperature increase. However, this assumes that the rate of increase stays constant. Given the past temperature history, it seems likely that temperatures will go through periods of little or no increase, suggesting that the overall temperature increase will be less than 2.5 degrees. If there are positive feedbacks, it is possible that temperatures will move up more quickly. However, even a 2.5 degree centigrade increase is nothing to take lightly. My advice, let’s see what happens in the next ten years as the Sun goes through its solar maximum. It temperatures begin to rise again, I think we have reason to be concerned. If the last 100 year’s increases are part of some natural climate variation, temperatures should level off soon. Time will tell. 
  • In conclusion,
    Global warming is happening 
    Most of the warming is probably the result of human activities 
    There will be positive but mostly negative repercussions from global warming 
    The costs to mitigate global warming will be high – better spent elsewhere? 
  • In conclusion,
    Global warming is happening 
    Most of the warming is probably the result of human activities 
    There will be positive but mostly negative repercussions from global warming 
    The costs to mitigate global warming will be high – better spent elsewhere? 
  • In conclusion,
    Global warming is happening 
    Most of the warming is probably the result of human activities 
    There will be positive but mostly negative repercussions from global warming 
    The costs to mitigate global warming will be high – better spent elsewhere? 
  • In conclusion,
    Global warming is happening 
    Most of the warming is probably the result of human activities 
    There will be positive but mostly negative repercussions from global warming 
    The costs to mitigate global warming will be high – better spent elsewhere? 
  • Global Warming

    1. 1. Global Warming Will Human-Induced Climate Change Destroy the World? By Rich Deem www.GodAndScience.org Note: This slideshow is NOT meant to be printed. View in slideshow mode only because of extensive builds and animations. Go to the website for a printable copy. Requires PowerPoint 2003 or PowerPoint Viewer 2003.
    2. 2. Introduction
    3. 3. Introduction • Is the world getting warmer?
    4. 4. Introduction • Is the world getting warmer? • If so, are the actions of mankind to blame for earth’s temperature increases?
    5. 5. Introduction • Is the world getting warmer? • If so, are the actions of mankind to blame for earth’s temperature increases? • What can/should be done about these issues?
    6. 6. Introduction • Is the world getting warmer? • If so, are the actions of mankind to blame for earth’s temperature increases? • What can/should be done about these issues? • Are the potential resolutions worth the cost to implement them?
    7. 7. History of Earth’s Climate
    8. 8. History of Earth’s Climate • Earth formed ~4.6 billion years ago
    9. 9. History of Earth’s Climate • Earth formed ~4.6 billion years ago • Originally very hot
    10. 10. History of Earth’s Climate • Earth formed ~4.6 billion years ago • Originally very hot • Sun’s energy output only 70% of present
    11. 11. History of Earth’s Climate • Earth formed ~4.6 billion years ago • Originally very hot • Sun’s energy output only 70% of present • Liquid water present ~4.3 billion years ago (zircon dating)
    12. 12. History of Earth’s Climate • Earth formed ~4.6 billion years ago • Originally very hot • Sun’s energy output only 70% of present • Liquid water present ~4.3 billion years ago (zircon dating) • Much of earth’s early history erased during late heavy bombardment (~3.9 billion years ago)
    13. 13. History of Earth’s Climate
    14. 14. History of Earth’s Climate • Life appeared ~3.8 billion years ago
    15. 15. History of Earth’s Climate • Life appeared ~3.8 billion years ago • Photosynthesis began 3.5-2.5 billion years ago
    16. 16. History of Earth’s Climate • Life appeared ~3.8 billion years ago • Photosynthesis began 3.5-2.5 billion years ago  Produced oxygen and removed carbon dioxide and methane (greenhouse gases)
    17. 17. History of Earth’s Climate • Life appeared ~3.8 billion years ago • Photosynthesis began 3.5-2.5 billion years ago  Produced oxygen and removed carbon dioxide and methane (greenhouse gases)  Earth went through periods of cooling (“Snowball Earth”) and warming
    18. 18. History of Earth’s Climate • Life appeared ~3.8 billion years ago • Photosynthesis began 3.5-2.5 billion years ago  Produced oxygen and removed carbon dioxide and methane (greenhouse gases)  Earth went through periods of cooling (“Snowball Earth”) and warming • Earth began cycles of glacial and interglacial periods ~3 million years ago
    19. 19. Earth’s Temperature
    20. 20. Earth’s Temperature Sun
    21. 21. Earth’s Temperature Sun Solar Energy
    22. 22. Solar Temperature Earth’s Energy Sun
    23. 23. Earth’s Temperature Sun Solar Energy
    24. 24. Earth’s Temperature Sun Radiative Cooling
    25. 25. Earth’s Temperature Solar Sun Energy
    26. 26. Earth’s Temperature Sun
    27. 27. Earth’s Temperature Sun Solar Energy
    28. 28. Earth’s Temperature Sun
    29. 29. Greenhouse Effect
    30. 30. Sun Greenhouse Effect
    31. 31. Sun Greenhouse Effect
    32. 32. Earth’s Atmospheric Gases
    33. 33. Earth’s Atmospheric Gases Nitrogen (N2)
    34. 34. Earth’s Atmospheric Gases Nitrogen (N2) Oxygen (O2)
    35. 35. Earth’s Atmospheric Gases Nitrogen (N2) Oxygen (O2) Argon (Ar)
    36. 36. Earth’s Atmospheric Gases Nitrogen (N2) Oxygen (O2) >99% Argon (Ar)
    37. 37. Earth’s Atmospheric Gases Nitrogen (N2) Non- Oxygen (O2) Greenhouse Gases Argon (Ar)
    38. 38. Earth’s Atmospheric Gases Nitrogen (N2) Non- Oxygen (O2) Greenhouse Gases Argon (Ar) Water (H2O)
    39. 39. Earth’s Atmospheric Gases Nitrogen (N2) Non- Oxygen (O2) Greenhouse Gases Argon (Ar) Water (H2O) Carbon Dioxide (CO2)
    40. 40. Earth’s Atmospheric Gases Nitrogen (N2) Non- Oxygen (O2) Greenhouse Gases Argon (Ar) Water (H2O) Carbon Dioxide (CO2) Methane (CH4)
    41. 41. Earth’s Atmospheric Gases Nitrogen (N2) Non- Oxygen (O2) Greenhouse Gases Argon (Ar) Water (H2O) Carbon Dioxide (CO2) <1% Methane (CH4)
    42. 42. Earth’s Atmospheric Gases Nitrogen (N2) Non- Oxygen (O2) Greenhouse Gases Argon (Ar) Water (H2O) Carbon Dioxide (CO2) Greenhouse Gases Methane (CH4)
    43. 43. Sun Runaway Greenhouse Effect
    44. 44. Sun Runaway Greenhouse Effect Venus
    45. 45. Sun Runaway Greenhouse Effect • 97% carbon dioxide Venus
    46. 46. Sun Runaway Greenhouse Effect • 97% carbon dioxide • 3% nitrogen Venus
    47. 47. Sun Runaway Greenhouse Effect • 97% carbon dioxide • 3% nitrogen • Water & sulfuric acid clouds Venus
    48. 48. Sun Runaway Greenhouse Effect • 97% carbon dioxide • 3% nitrogen • Water & sulfuric acid clouds • Temperature: Venus 860°F
    49. 49. Carbon Dioxide
    50. 50. Carbon Dioxide Levels 420 370 CO2 (ppm) 320 270 220 Dome Concordia Vostok Ice Core 170 600000 400000 200000 0 Time (YBP)
    51. 51. Carbon Dioxide Levels 420 370 CO2 (ppm) 320 270 220 Dome Concordia Vostok Ice Core 170 600000 400000 200000 0 Time (YBP)
    52. 52. Carbon Dioxide Levels 420 Muana Loa Readings CO2 Levels Since 1958 CO2 (ppm) 370 370 350 CO2 (ppm) 330 320 310 40 30 20 10 0 270 220 Dome Concordia Vostok Ice Core 170 600000 400000 200000 0 Time (YBP)
    53. 53. Worldwide Carbon Emissions 8 Carbon (109 metric tons) Total 7 Liquid fuel 6 Solid fuel Gas fuel 5 4 3 2 1 0 1750 1800 1850 1900 1950 2000 Year
    54. 54. Worldwide Carbon Emissions 8 Carbon (109 metric tons) Total 7 Liquid fuel 6 Solid fuel Gas fuel 5 4 3 2 1 0 1750 1800 1850 1900 1950 2000 Year
    55. 55. Worldwide Carbon Emissions 8 Carbon (109 metric tons) Total 7 Liquid fuel 6 Solid fuel Gas fuel 5 4 3 2 1 0 1750 1800 1850 1900 1950 2000 Year
    56. 56. Worldwide Carbon Emissions 8 Carbon (109 metric tons) Total 7 Liquid fuel 6 Solid fuel Gas fuel 5 4 3 2 1 0 1750 1800 1850 1900 1950 2000 Year
    57. 57. Worldwide Carbon Emissions 8 Carbon (109 metric tons) Total 7 Liquid fuel 6 Solid fuel Gas fuel 5 4 3 2 1 0 1750 1800 1850 1900 1950 2000 Year
    58. 58. Carbon (109 metric tons) 8 Annual Carbon Emissions 6 4 2 0 1955 1965 1975 1985 1995 2005 Year
    59. 59. Carbon (109 metric tons) 8 Annual Carbon Emissions Annual carbon emissions 6 4 2 0 1955 1965 1975 1985 1995 2005 Year
    60. 60. Carbon (109 metric tons) 8 Annual Carbon Emissions Annual carbon emissions Atmospheric CO2 6 Atmospheric CO2 average 4 2 0 1955 1965 1975 1985 1995 2005 Year
    61. 61. Future Carbon Dioxide Levels
    62. 62. Future Carbon Dioxide Levels • Increasing CO2 emissions, especially in China and developing countries
    63. 63. Future Carbon Dioxide Levels • Increasing CO2 emissions, especially in China and developing countries • Likely to double within 150 years:
    64. 64. Future Carbon Dioxide Levels • Increasing CO2 emissions, especially in China and developing countries • Likely to double within 150 years:  Increased coal usage
    65. 65. Future Carbon Dioxide Levels • Increasing CO2 emissions, especially in China and developing countries • Likely to double within 150 years:  Increased coal usage  Increased natural gas usage
    66. 66. Future Carbon Dioxide Levels • Increasing CO2 emissions, especially in China and developing countries • Likely to double within 150 years:  Increased coal usage  Increased natural gas usage  Decreased petroleum usage (increased cost and decreasing supply)
    67. 67. Kyoto Protocol
    68. 68. Kyoto Protocol • Adopted in 1997
    69. 69. Kyoto Protocol • Adopted in 1997 • Cut CO2 emissions by 5% from 1990 levels for 2008-2012
    70. 70. Kyoto Protocol • Adopted in 1997 • Cut CO2 emissions by 5% from 1990 levels for 2008-2012 • Symbolic only, since cuts will not significantly impact global warming
    71. 71. Past Temperatures
    72. 72. Recorded Worldwide Temperatures 0.8 0.6 Δ Mean Temperature (°C) 0.4 0.2 0.0 -0.2 -0.4 -0.6 1880 1900 1920 1940 1960 1980 2000 Year
    73. 73. Recorded Worldwide Temperatures 0.8 0.6 Δ Mean Temperature (°C) 0.4 0.2 0.0 -0.2 -0.4 -0.6 1880 1900 1920 1940 1960 1980 2000 Year
    74. 74. Recorded Worldwide Temperatures 0.8 0.6 Δ Mean Temperature (°C) 0.4 Flat 0.2 0.0 -0.2 -0.4 -0.6 1880 1900 1920 1940 1960 1980 2000 Year
    75. 75. Recorded Worldwide Temperatures 0.8 0.6 Δ Mean Temperature (°C) 0.4 Decreasing Flat 0.2 0.0 -0.2 -0.4 -0.6 1880 1900 1920 1940 1960 1980 2000 Year
    76. 76. Recorded Worldwide Flat Temperatures 0.8 0.6 Δ Mean Temperature (°C) 0.4 Decreasing Flat 0.2 0.0 -0.2 -0.4 -0.6 1880 1900 1920 1940 1960 1980 2000 Year
    77. 77. Historic Los Angeles Temperatures
    78. 78. Historic Los Angeles Temperatures Annual Temperatures 22 21 20 Temperature (°C) 19 18 17 16 15 1880 1900 1920 1940 1960 1980 2000 Year
    79. 79. Historic Los Angeles Temperatures Annual Temperatures 22 21 20 Temperature (°C) 19 18 17 16 15 1880 1900 1920 1940 1960 1980 2000 Year
    80. 80. Historic Los Angeles Temperatures Annual Temperatures Summer Temperatures 22 25 21 24 20 23 Temperature (°C) 19 22 18 21 17 20 16 19 15 18 1880 1900 1920 1940 1960 1980 2000 1880 1900 1920 1940 1960 1980 2000 Year Year
    81. 81. Historic Los Angeles Temperatures Annual Temperatures Summer Temperatures 22 25 21 24 20 23 Temperature (°C) 19 22 18 21 17 20 16 19 15 18 1880 1900 1920 1940 1960 1980 2000 1880 1900 1920 1940 1960 1980 2000 Year Year
    82. 82. Historic Los Angeles Temperatures Annual Temperatures Summer Temperatures 22 25 21 24 20 23 Temperature (°C) 19 22 18 21 17 20 16 19 15 18 1880 1900 1920 1940 1960 1980 2000 1880 1900 1920 1940 1960 1980 2000 Year Year
    83. 83. Historic Los Angeles Temperatures Annual Temperatures Summer Temperatures Winter Temperatures 22 25 17 21 24 16 20 23 15 Temperature (°C) 19 22 14 18 21 13 17 20 12 16 19 11 15 18 10 1880 1900 1920 1940 1960 1980 2000 1880 1900 1920 1940 1960 1980 2000 1880 1900 1920 1940 1960 1980 2000 Year Year Year
    84. 84. 2009 Temperature Changes Compared to 1951-1980 2009 Temperature Changes Compared to 1951-1980 -4.1 -4 -2 -1 -.5 -.2 .2 .5 1 2 4 4.1
    85. 85. 2009 Temperature Changes Compared to 1951-1980 2009 Temperature Changes Compared to 1951-1980 -4.1 -4 -2 -1 -.5 -.2 .2 .5 1 2 4 4.1
    86. 86. 2009 Temperature Changes Compared to 1951-1980 2009 Temperature Changes Compared to 1951-1980 -4.1 -4 -2 -1 -.5 -.2 .2 .5 1 2 4 4.1
    87. 87. Past Temperatures Measurement
    88. 88. Past Temperatures Measurement • Proxy – a method that approximates a particular measurement (e.g., temperature)
    89. 89. Past Temperatures Measurement • Proxy – a method that approximates a particular measurement (e.g., temperature)  Tree rings
    90. 90. Past Temperatures Measurement • Proxy – a method that approximates a particular measurement (e.g., temperature)  Tree rings  Ice cores
    91. 91. Past Temperatures Measurement • Proxy – a method that approximates a particular measurement (e.g., temperature)  Tree rings  Ice cores  Pollen records
    92. 92. Past Temperatures Measurement • Proxy – a method that approximates a particular measurement (e.g., temperature)  Tree rings  Ice cores  Pollen records  Plant macrofossils
    93. 93. Past Temperatures Measurement • Proxy – a method that approximates a particular measurement (e.g., temperature)  Tree rings  Ice cores  Pollen records  Plant macrofossils  Sr/Ca isotope data
    94. 94. Past Temperatures Measurement • Proxy – a method that approximates a particular measurement (e.g., temperature)  Tree rings  Ice cores  Pollen records  Plant macrofossils  Sr/Ca isotope data  Oxygen isotopes from speleothem calcite (stalactites and stalagmites)
    95. 95. Temperature History of the Earth
    96. 96. Temperature History of the Earth • Little ice age (1400-1840) – 1°C cooler
    97. 97. Temperature History of the Earth • Little ice age (1400-1840) – 1°C cooler • Medieval warm period (800-1300) – 1°C warmer than today
    98. 98. Temperature History of the Earth • Little ice age (1400-1840) – 1°C cooler • Medieval warm period (800-1300) – 1°C warmer than today • Cool/warm cycles occur ~1,500 years
    99. 99. Temperature History of the Earth • Little ice age (1400-1840) – 1°C cooler • Medieval warm period (800-1300) – 1°C warmer than today • Cool/warm cycles occur ~1,500 years • Affect mostly Northeastern U.S. and North Atlantic
    100. 100. Temperature History of the Earth • Little ice age (1400-1840) – 1°C cooler • Medieval warm period (800-1300) – 1°C warmer than today • Cool/warm cycles occur ~1,500 years • Affect mostly Northeastern U.S. and North Atlantic • Mostly due to changes in thermohaline circulation →
    101. 101. Temperature History of the Earth • Little ice age (1400-1840) – 1°C cooler • Medieval warm period (800-1300) – 1°C warmer than today • Cool/warm cycles occur ~1,500 years • Affect mostly Northeastern U.S. and North Atlantic • Mostly due to changes in thermohaline circulation →
    102. 102. Temperature History of the Earth • Little ice age (1400-1840) – 1°C cooler • Medieval warm period (800-1300) – 1°C warmer than today • Cool/warm cycles occur ~1,500 years • Affect mostly Northeastern U.S. and North Atlantic • Mostly due to changes in thermohaline circulation →
    103. 103. Temperature History of the Earth • Little ice age (1400-1840) – 1°C cooler • Medieval warm period (800-1300) – 1°C warmer than today • Cool/warm cycles occur ~1,500 years • Affect mostly Northeastern U.S. and North Atlantic • Mostly due to changes in thermohaline circulation → • Dramatic shutdown of thermohaline circulation occurred 8,200 years ago as a large lake in Canada flooded the North Atlantic
    104. 104. Main Ocean Currents Adapted from IPCC SYR Figure 4-2
    105. 105. Main Ocean Currents Adapted from IPCC SYR Figure 4-2
    106. 106. Main Ocean Currents Adapted from IPCC SYR Figure 4-2
    107. 107. Main Ocean Currents Adapted from IPCC SYR Figure 4-2
    108. 108. Temperature History of the Earth
    109. 109. Temperature History of the Earth • For the past 3 million years, the earth has been experiencing ~100,000 year long cycles of glaciation followed by ~10,000 year long interglacial periods
    110. 110. Temperature History of the Earth • For the past 3 million years, the earth has been experiencing ~100,000 year long cycles of glaciation followed by ~10,000 year long interglacial periods • These climate periods are largely the result of cycles in the earth’s orbit – precession, obliquity, and eccentricity
    111. 111. Orbital Parameters: Precession Apehelion Perihelion
    112. 112. Orbital Parameters: Precession Apehelion Perihelion
    113. 113. Orbital Parameters: Precession Apehelion Perihelion
    114. 114. Orbital Parameters: Precession Apehelion Perihelion
    115. 115. Orbital Parameters: Precession Apehelion Perihelion
    116. 116. Orbital Parameters: Precession Apehelion Perihelion
    117. 117. Orbital Parameters: Precession Apehelion Perihelion
    118. 118. Orbital Parameters: Obliquity
    119. 119. Orbital Parameters: Obliquity 22.5°
    120. 120. Orbital Parameters: Obliquity
    121. 121. Orbital Parameters: Obliquity 24.5°
    122. 122. Orbital Parameters: Eccentricity
    123. 123. Orbital Parameters: Eccentricity Apehelion Perihelion Not to scale!
    124. 124. Orbital Parameters: Eccentricity Maximum: 0.061 Apehelion Perihelion Not to scale!
    125. 125. Orbital Parameters: Eccentricity Maximum: 0.061 Minimum: 0.005 Apehelion Perihelion Not to scale!
    126. 126. Orbital Parameters: Eccentricity Maximum: 0.061 To Scale!
    127. 127. Orbital Parameters & Earth’s Climate 1000 900 800 700 600 500 400 300 200 100 0 Age (kya)
    128. 128. Orbital Parameters & Earth’s Climate Precession (22 ky) 1000 900 800 700 600 500 400 300 200 100 0 Age (kya)
    129. 129. Orbital Parameters & Earth’s Climate Precession (22 ky) Obliquity (41 ky) 1000 900 800 700 600 500 400 300 200 100 0 Age (kya)
    130. 130. Orbital Parameters & Earth’s Climate Precession (22 ky) Obliquity (41 ky) Eccentricity (100 ky) 1000 900 800 700 600 500 400 300 200 100 0 Age (kya)
    131. 131. Orbital Parameters & Earth’s Climate Precession (22 ky) Obliquity (41 ky) Eccentricity (100 ky) Temperature 1000 900 800 700 600 500 400 300 200 100 0 Age (kya)
    132. 132. Orbital Parameters & Earth’s Climate Precession (22 ky) Obliquity (41 ky) Eccentricity (100 ky) Temperature 1000 900 800 700 600 500 400 300 200 100 0 Age (kya)
    133. 133. Temperature History of the Earth
    134. 134. Temperature History of the Earth • For the past 3 million years, the earth has been experiencing ~100,000 year long cycles of glaciation followed by ~10,000 year long interglacial periods
    135. 135. Temperature History of the Earth • For the past 3 million years, the earth has been experiencing ~100,000 year long cycles of glaciation followed by ~10,000 year long interglacial periods • Last ice age began to thaw 15,000 years ago, but was interrupted by the “Younger Dryas” event 12,900 years ago
    136. 136. Younger Dryas Event -25 0.35 Snow Accumulation (m/yr) -30 0.30 Temperature (°C) -35 0.25 -40 0.20 -45 0.15 -50 0.10 -55 0.05 20 15 10 5 0 Age (kya)
    137. 137. Younger Dryas Event -25 0.35 Snow Accumulation (m/yr) -30 0.30 Temperature (°C) -35 0.25 -40 0.20 -45 0.15 -50 0.10 -55 0.05 20 15 10 5 0 Age (kya)
    138. 138. Younger Dryas Event -25 0.35 Snow Accumulation (m/yr) -30 0.30 Temperature (°C) -35 0.25 -40 Ice Age 0.20 -45 0.15 -50 0.10 -55 0.05 20 15 10 5 0 Age (kya)
    139. 139. Younger Dryas Event -25 0.35 Snow Accumulation (m/yr) -30 0.30 Temperature (°C) -35 0.25 -40 Ice Age 0.20 -45 0.15 -50 0.10 -55 0.05 20 15 10 5 0 Age (kya)
    140. 140. Younger Dryas Event -25 0.35 Snow Accumulation (m/yr) -30 0.30 Temperature (°C) -35 0.25 -40 Ice Age 0.20 -45 0.15 -50 0.10 -55 0.05 20 15 10 5 0 Age (kya)
    141. 141. Younger Dryas Event -25 0.35 Younger Snow Accumulation (m/yr) Dryas -30 0.30 Temperature (°C) -35 0.25 -40 Ice Age 0.20 -45 0.15 -50 0.10 -55 0.05 20 15 10 5 0 Age (kya)
    142. 142. Younger Dryas Event -25 0.35 Younger Snow Accumulation (m/yr) Dryas -30 0.30 Temperature (°C) -35 0.25 -40 Ice Age 0.20 -45 0.15 -50 0.10 -55 0.05 20 15 10 5 0 Age (kya)
    143. 143. Younger Dryas Event -25 0.35 Younger Snow Accumulation (m/yr) Dryas -30 0.30 Temperature (°C) -35 0.25 -40 Ice Age 0.20 -45 0.15 -50 0.10 -55 0.05 20 15 10 5 0 Age (kya)
    144. 144. Younger Dryas Event -25 0.35 Younger Snow Accumulation (m/yr) Dryas -30 0.30 Temperature (°C) Medieval Warm -35 0.25 -40 Ice Age 0.20 -45 0.15 -50 0.10 -55 0.05 20 15 10 5 0 Age (kya)
    145. 145. Younger Dryas Event -25 0.35 Younger Snow Accumulation (m/yr) Dryas -30 0.30 Temperature (°C) Medieval Warm -35 0.25 -40 Ice Age Little Ice Age 0.20 -45 0.15 -50 0.10 -55 0.05 20 15 10 5 0 Age (kya)
    146. 146. Younger Dryas Event -8.0 -34 Younger -7.5 Dryas -35 -36 -7.0 δ18O (Greenland) -37 δ18O (China) -6.5 -38 -6.0 -39 -5.5 -40 -41 -5.0 -42 -4.5 -43 -4.0 -44 16 15 14 13 12 11 10 Age (kya)
    147. 147. Younger Dryas Event -8.0 -34 Younger -7.5 Dryas -35 -36 -7.0 δ18O (Greenland) -37 δ18O (China) -6.5 -38 -6.0 -39 -5.5 -40 -41 -5.0 -42 -4.5 -43 -4.0 -44 16 15 14 13 12 11 10 Age (kya)
    148. 148. Younger Dryas Event -8.0 -34 Younger -7.5 Dryas -35 -36 -7.0 δ18O (Greenland) -37 δ18O (China) -6.5 -38 -6.0 -39 -5.5 -40 -41 -5.0 -42 -4.5 -43 -4.0 -44 16 15 14 13 12 11 10 Age (kya)
    149. 149. Temperature History of the Earth
    150. 150. Temperature History of the Earth Middle Pliocene (3.15 to 2.85 million ya)
    151. 151. Temperature History of the Earth Middle Pliocene (3.15 to 2.85 million ya) • Temperatures: 2°C higher than today.
    152. 152. Temperature History of the Earth Middle Pliocene (3.15 to 2.85 million ya) • Temperatures: 2°C higher than today.  20°C higher at high latitudes
    153. 153. Temperature History of the Earth Middle Pliocene (3.15 to 2.85 million ya) • Temperatures: 2°C higher than today.  20°C higher at high latitudes  1°C higher at the Equator
    154. 154. Temperature History of the Earth Middle Pliocene (3.15 to 2.85 million ya) • Temperatures: 2°C higher than today.  20°C higher at high latitudes  1°C higher at the Equator • Sea levels were 100 ft higher
    155. 155. Temperature History of the Earth Middle Pliocene (3.15 to 2.85 million ya) • Temperatures: 2°C higher than today.  20°C higher at high latitudes  1°C higher at the Equator • Sea levels were 100 ft higher • Causes
    156. 156. Temperature History of the Earth Middle Pliocene (3.15 to 2.85 million ya) • Temperatures: 2°C higher than today.  20°C higher at high latitudes  1°C higher at the Equator • Sea levels were 100 ft higher • Causes  CO2 levels that were 100 ppm higher
    157. 157. Temperature History of the Earth Middle Pliocene (3.15 to 2.85 million ya) • Temperatures: 2°C higher than today.  20°C higher at high latitudes  1°C higher at the Equator • Sea levels were 100 ft higher • Causes  CO2 levels that were 100 ppm higher  Increased thermohaline circulation
    158. 158. Temperature History of the Earth
    159. 159. Temperature History of the Earth Eocene (41 million years ago)
    160. 160. Temperature History of the Earth Eocene (41 million years ago) • Opening of the Drake Passage (between South America and Antarctica).
    161. 161. Temperature History of the Earth Eocene (41 million years ago) • Opening of the Drake Passage (between South America and Antarctica). • Increased ocean current exchange
    162. 162. Temperature History of the Earth Eocene (41 million years ago) • Opening of the Drake Passage (between South America and Antarctica). • Increased ocean current exchange  Strong global cooling
    163. 163. Temperature History of the Earth Eocene (41 million years ago) • Opening of the Drake Passage (between South America and Antarctica). • Increased ocean current exchange  Strong global cooling  First permanent glaciation of Antarctica ~34 million years ago
    164. 164. Temperature History of the Earth
    165. 165. Temperature History of the Earth Paleocene Thermal Maximum (55 mya)
    166. 166. Temperature History of the Earth Paleocene Thermal Maximum (55 mya) • Sea surface temperatures rose 5-8°C
    167. 167. Temperature History of the Earth Paleocene Thermal Maximum (55 mya) • Sea surface temperatures rose 5-8°C • Causes
    168. 168. Temperature History of the Earth Paleocene Thermal Maximum (55 mya) • Sea surface temperatures rose 5-8°C • Causes  Increased volcanism
    169. 169. Temperature History of the Earth Paleocene Thermal Maximum (55 mya) • Sea surface temperatures rose 5-8°C • Causes  Increased volcanism  Rapid release of methane from the oceans
    170. 170. Temperature History of the Earth
    171. 171. Temperature History of the Earth Mid-Cretaceous (120-90 mya)
    172. 172. Temperature History of the Earth Mid-Cretaceous (120-90 mya) • Much warmer
    173. 173. Temperature History of the Earth Mid-Cretaceous (120-90 mya) • Much warmer • Breadfruit trees grew in Greenland
    174. 174. Temperature History of the Earth Mid-Cretaceous (120-90 mya) • Much warmer • Breadfruit trees grew in Greenland • Causes
    175. 175. Temperature History of the Earth Mid-Cretaceous (120-90 mya) • Much warmer • Breadfruit trees grew in Greenland • Causes  Different ocean currents (continental arrangement)
    176. 176. Temperature History of the Earth Mid-Cretaceous (120-90 mya) • Much warmer • Breadfruit trees grew in Greenland • Causes  Different ocean currents (continental arrangement)  higher CO2 levels (at least 2 to 4 times higher than today, up to 1200 ppm)
    177. 177. A Compilation of Phanerozoic Atmospheric CO2 Records 6000 5000 Concentration (ppmV) Atmospheric CO2 4000 3000 2000 1000 0 30 Continental Glaciation (Paleolatitude) 60 S D Carb P Tr J K Pg Ng 90 Paleozoic Mesozoic Cenozoic 400 300 200 100 0 Breecker D O et al. PNAS 2010;107:576-580
    178. 178. Recent Temperature Changes
    179. 179. “Hockey Stick” Controversy 0.6 Temperature Change (°C) Direct temperature measurements 0.4 Mann et al. 1999 0.2 0 -0.2 -0.4 -0.6 -0.8 1000 1200 1400 1600 1800 2000 Year
    180. 180. “Hockey Stick” Controversy 0.6 Temperature Change (°C) Direct temperature measurements 0.4 Mann et al. 1999 0.2 0 -0.2 -0.4 -0.6 -0.8 1000 1200 1400 1600 1800 2000 Year
    181. 181. “Hockey Stick” Controversy 0.6 Temperature Change (°C) Direct temperature measurements 0.4 Mann et al. 1999 0.2 0 -0.2 -0.4 -0.6 -0.8 1000 1200 1400 1600 1800 2000 Year
    182. 182. “Hockey Stick” Controversy 0.6 Temperature Change (°C) Direct temperature measurements 0.4 Mann et al. 1999 0.2 0 -0.2 -0.4 -0.6 -0.8 1000 1200 1400 1600 1800 2000 Year
    183. 183. “Hockey Stick” Controversy 0.6 Temperature Change (°C) Direct temperature measurements 0.4 Mann et al. 1999 0.2 0 -0.2 -0.4 -0.6 -0.8 1000 1200 1400 1600 1800 2000 Year
    184. 184. The Problem with Tree Rings 0.3 Jones et al. 1998 Temperature Change (°C) 0.2 Briffa et al. 1999 Mann et al. 1999 0.1 0 -0.1 -0.2 -0.3 -0.4 -0.5 -0.6 1000 1200 1400 1600 1800 2000 Year
    185. 185. The Problem with Tree Rings 0.3 Jones et al. 1998 Temperature Change (°C) 0.2 Briffa et al. 1999 Mann et al. 1999 0.1 0 -0.1 -0.2 -0.3 -0.4 -0.5 -0.6 1000 1200 1400 1600 1800 2000 Year
    186. 186. The Problem with Tree Rings 0.3 Jones et al. 1998 Temperature Change (°C) 0.2 Briffa et al. 1999 Mann et al. 1999 0.1 0 -0.1 -0.2 -0.3 -0.4 -0.5 -0.6 1000 1200 1400 1600 1800 2000 Year
    187. 187. The Problem with Tree Rings 0.3 Jones et al. 1998 Temperature Change (°C) 0.2 Briffa et al. 1999 Mann et al. 1999 0.1 0 -0.1 -0.2 -0.3 -0.4 -0.5 -0.6 1000 1200 1400 1600 1800 2000 Year
    188. 188. The Problem with Tree Rings 0.3 Jones et al. 1998 Temperature Change (°C) 0.2 Briffa et al. 1999 Mann et al. 1999 0.1 0 -0.1 -0.2 -0.3 -0.4 -0.5 -0.6 1000 1200 1400 1600 1800 2000 Year
    189. 189. The Problem with Tree Rings 0.3 Jones et al. 1998 Temperature Change (°C) 0.2 Briffa et al. 1999 Mann et al. 1999 0.1 0 -0.1 -0.2 -0.3 -0.4 -0.5 -0.6 1000 1200 1400 1600 1800 2000 Year
    190. 190. The Problem with Tree Rings 0.3 Jones et al. 1998 Temperature Change (°C) 0.2 Briffa et al. 1999 Mann et al. 1999 0.1 0 -0.1 -0.2 -0.3 -0.4 -0.5 -0.6 1000 1200 1400 1600 1800 2000 Year
    191. 191. The Problem with Tree Rings 0.3 Jones et al. 1998 Temperature Change (°C) 0.2 Briffa et al. 1999 Mann et al. 1999 0.1 0 -0.1 -0.2 -0.3 -0.4 -0.5 -0.6 1000 1200 1400 1600 1800 2000 Year
    192. 192. The Problem with Tree Rings 0.3 Jones et al. 1998 Temperature Change (°C) 0.2 Briffa et al. 1999 Mann et al. 1999 0.1 0 -0.1 -0.2 -0.3 -0.4 -0.5 -0.6 1000 1200 1400 1600 1800 2000 Year
    193. 193. What Influences Tree Rings?
    194. 194. What Influences Tree Rings? • Temperature
    195. 195. What Influences Tree Rings? • Temperature • Rainfall
    196. 196. What Influences Tree Rings? • Temperature • Rainfall • Carbon dioxide concentration
    197. 197. Is the Hockey Stick Correct? 2 Temperature Change (°C) Mann et al. 1999 Esper et al. 2002 1 0 -1 -2 800 1000 1200 1400 1600 1800 2000 Year
    198. 198. Is the Hockey Stick Correct? 2 Temperature Change (°C) Mann et al. 1999 Esper et al. 2002 1 0 -1 -2 800 1000 1200 1400 1600 1800 2000 Year
    199. 199. Is the Hockey Stick Correct? 2 Temperature Change (°C) Mann et al. 1999 Esper et al. 2002 1 0 -1 -2 800 1000 1200 1400 1600 1800 2000 Year
    200. 200. Is the Hockey Stick Correct? 0.4 Temperature Change (°C) 0.2 0.0 -0.2 -0.4 -0.6 Mann et al. 1999 -0.8 Esper et al. 2002 -1.0 Moberg et al. 2005 Mann et al. 2008 -1.2 0 400 800 1200 1600 2000 Year
    201. 201. Is the Hockey Stick Correct? 0.4 Temperature Change (°C) 0.2 0.0 -0.2 -0.4 -0.6 Mann et al. 1999 -0.8 Esper et al. 2002 -1.0 Moberg et al. 2005 Mann et al. 2008 -1.2 0 400 800 1200 1600 2000 Year
    202. 202. Is the Hockey Stick Correct? 0.4 Temperature Change (°C) 0.2 0.0 -0.2 -0.4 -0.6 Mann et al. 1999 -0.8 Esper et al. 2002 -1.0 Moberg et al. 2005 Mann et al. 2008 -1.2 0 400 800 1200 1600 2000 Year
    203. 203. Is the Hockey Stick Correct? 0.4 Temperature Change (°C) 0.2 0.0 -0.2 -0.4 -0.6 Mann et al. 1999 -0.8 Esper et al. 2002 -1.0 Moberg et al. 2005 Mann et al. 2008 -1.2 0 400 800 1200 1600 2000 Year
    204. 204. Is the Hockey Stick Correct? 0.4 Temperature Change (°C) 0.2 0.0 -0.2 -0.4 -0.6 Mann et al. 1999 -0.8 Esper et al. 2002 -1.0 Moberg et al. 2005 Mann et al. 2008 -1.2 0 400 800 1200 1600 2000 Year
    205. 205. Is the Hockey Stick Correct? 0.4 Medieval Warm Period Temperature Change (°C) 0.2 0.0 -0.2 -0.4 -0.6 Mann et al. 1999 -0.8 Esper et al. 2002 -1.0 Moberg et al. 2005 Mann et al. 2008 -1.2 0 400 800 1200 1600 2000 Year
    206. 206. U.S. National Academy of Sciences: June 2006 0.6 Temperature Change (°C) 0.4 0.2 0 -0.2 -0.4 -0.6 -0.8 1000 1200 1400 1600 1800 2000 Year
    207. 207. U.S. National Academy of Sciences: June 2006 0.6 Temperature Change (°C) “high level of confidence” 0.4 0.2 0 -0.2 -0.4 -0.6 -0.8 1000 1200 1400 1600 1800 2000 Year
    208. 208. U.S. National Academy of Sciences: June 2006 0.6 Temperature Change (°C) “2:1 chance of being right” “high level of confidence” 0.4 0.2 0 -0.2 -0.4 -0.6 -0.8 1000 1200 1400 1600 1800 2000 Year
    209. 209. Atmospheric Temperatures Troposphere Stratosphere 0.8 1.5 Temperature Cgange (°C) 0.6 1.0 0.4 0.2 0.5 0.0 0.0 -0.2 -0.5 -0.4 -0.6 -1.0 1980 1990 2000 1980 1990 2000 Year Year
    210. 210. Atmospheric Temperatures Troposphere Stratosphere 0.8 1.5 Temperature Cgange (°C) 0.6 1.0 0.4 0.2 0.5 0.0 0.0 -0.2 -0.5 -0.4 -0.6 -1.0 1980 1990 2000 1980 1990 2000 Year Year
    211. 211. Atmospheric Temperatures Troposphere Stratosphere 0.8 1.5 Temperature Cgange (°C) 0.6 1.0 0.4 0.2 0.5 0.0 0.0 -0.2 -0.5 -0.4 -0.6 -1.0 1980 1990 2000 1980 1990 2000 Year Year
    212. 212. CO2 Concentration Vs. Temperature 370 SST (°C) Tropical Pacific CO2 (ppm) Antarctica 320 31 30 270 29 28 220 27 26 170 25 600000 400000 200000 0 Time (YBP)
    213. 213. CO2 Concentration Vs. Temperature 370 SST (°C) Tropical Pacific CO2 (ppm) Antarctica 320 31 30 270 29 28 220 27 26 170 25 600000 400000 200000 0 Time (YBP)
    214. 214. CO2 Concentration Vs. Temperature 370 SST (°C) Tropical Pacific CO2 (ppm) Antarctica 320 31 30 270 29 28 220 27 26 170 25 600000 400000 200000 0 Time (YBP)
    215. 215. Consequences of Global Warming
    216. 216. Global Warming Primarily Impacts the Northern Hemisphere Northern vs. Southern Latitude Land vs. Ocean 1.0 Temperature Change (°C) Northern Hemisphere Land 0.8 Southern Hemisphere Ocean 0.6 0.4 0.2 0.0 -0.2 -0.4 -0.6 1920 1960 2000 1920 1960 2000 Year Year
    217. 217. Global Warming Primarily Impacts the Northern Hemisphere Northern vs. Southern Latitude Land vs. Ocean 1.0 Temperature Change (°C) Northern Hemisphere Land 0.8 Southern Hemisphere Ocean 0.6 0.4 0.2 0.0 -0.2 -0.4 -0.6 1920 1960 2000 1920 1960 2000 Year Year
    218. 218. Global Warming Primarily Impacts the Northern Hemisphere Northern vs. Southern Latitude Land vs. Ocean 1.0 Temperature Change (°C) Northern Hemisphere Land 0.8 Southern Hemisphere Ocean 0.6 0.4 0.2 0.0 -0.2 -0.4 -0.6 1920 1960 2000 1920 1960 2000 Year Year
    219. 219. Global Warming Primarily Impacts the Northern Hemisphere Northern vs. Southern Latitude Land vs. Ocean 1.0 Temperature Change (°C) Northern Hemisphere Land 0.8 Southern Hemisphere Ocean 0.6 0.4 0.2 0.0 -0.2 -0.4 -0.6 1920 1960 2000 1920 1960 2000 Year Year
    220. 220. Global Warming Primarily Impacts the Northern Hemisphere Northern vs. Southern Latitude Land vs. Ocean 1.0 Temperature Change (°C) Northern Hemisphere Land 0.8 Southern Hemisphere Ocean 0.6 0.4 0.2 0.0 -0.2 -0.4 -0.6 1920 1960 2000 1920 1960 2000 Year Year
    221. 221. 2009 Temperature Changes Compared to 1951-1980 -4.1 -4 -2 -1 -.5 -.2 .2 .5 1 2 4 4.1
    222. 222. Ice Sheets Melting?
    223. 223. Ice Sheets Melting? • GRACE (gravity measured by satellite) found melting of Antarctica equivalent to sea level rise of 0.4 mm/year (2 in/ century)
    224. 224. Ice Sheets Melting? • GRACE (gravity measured by satellite) found melting of Antarctica equivalent to sea level rise of 0.4 mm/year (2 in/ century) • Zwally, 2005 (satellite radar altimetry)
    225. 225. Ice Sheets Melting? • GRACE (gravity measured by satellite) found melting of Antarctica equivalent to sea level rise of 0.4 mm/year (2 in/ century) • Zwally, 2005 (satellite radar altimetry)  confirmed Antarctica melting
    226. 226. Ice Sheets Melting? • GRACE (gravity measured by satellite) found melting of Antarctica equivalent to sea level rise of 0.4 mm/year (2 in/ century) • Zwally, 2005 (satellite radar altimetry)  confirmed Antarctica melting  Greenland ice melting on exterior, accumulating inland (higher precipitation)
    227. 227. Ice Sheets Melting? • GRACE (gravity measured by satellite) found melting of Antarctica equivalent to sea level rise of 0.4 mm/year (2 in/ century) • Zwally, 2005 (satellite radar altimetry)  confirmed Antarctica melting  Greenland ice melting on exterior, accumulating inland (higher precipitation)
    228. 228. Melting Glaciers – Mt. Kilimanjaro
    229. 229. Melting Glaciers – Mt. Kilimanjaro
    230. 230. Changes in Antarctica Ice Mass 1000 800 600 Ice Mass (km3) 400 200 0 -200 -400 -600 2003 2004 2005 Year
    231. 231. Changes in Antarctica Ice Mass 1000 800 600 Ice Mass (km3) 400 200 0 -200 -400 -600 2003 2004 2005 Year
    232. 232. Rise in Sea Levels?
    233. 233. Rise in Sea Levels? • Present rate is 1.8 ± 0.3 mm/yr (7.4 in/ century)
    234. 234. Rise in Sea Levels? • Present rate is 1.8 ± 0.3 mm/yr (7.4 in/ century) • Accelerating at a rate of 0.013 ± 0.006 mm/yr2
    235. 235. Rise in Sea Levels? • Present rate is 1.8 ± 0.3 mm/yr (7.4 in/ century) • Accelerating at a rate of 0.013 ± 0.006 mm/yr2 • If acceleration continues, could result in 12 in/century sea level rise
    236. 236. Rise in Sea Levels? • Present rate is 1.8 ± 0.3 mm/yr (7.4 in/ century) • Accelerating at a rate of 0.013 ± 0.006 mm/yr2 • If acceleration continues, could result in 12 in/century sea level rise • Scenarios claiming 1 meter or more rise are unrealistic
    237. 237. Changing Sea Levels 20 Relative Sea Level (cm) 10 0 -10 Amsterdam, Netherlands Brest, France Swinoujscie, Poland -20 1700 1750 1800 1850 1900 1950 2000 Adapted from IPCC SYR Figure 2-5
    238. 238. Changing Sea Levels 20 Relative Sea Level (cm) 10 0 -10 Amsterdam, Netherlands Brest, France Swinoujscie, Poland -20 1700 1750 1800 1850 1900 1950 2000 Adapted from IPCC SYR Figure 2-5
    239. 239. Changing Sea Levels 20 Relative Sea Level (cm) 10 0 -10 Amsterdam, Netherlands Brest, France Swinoujscie, Poland -20 1700 1750 1800 1850 1900 1950 2000 Adapted from IPCC SYR Figure 2-5
    240. 240. Changing Sea Levels 20 Relative Sea Level (cm) 10 0 -10 Amsterdam, Netherlands Brest, France Swinoujscie, Poland -20 1700 1750 1800 1850 1900 1950 2000 Adapted from IPCC SYR Figure 2-5
    241. 241. Changing Sea Levels 20 Relative Sea Level (cm) 10 0 -10 Amsterdam, Netherlands Brest, France Swinoujscie, Poland -20 1700 1750 1800 1850 1900 1950 2000 Adapted from IPCC SYR Figure 2-5
    242. 242. Changing Sea Levels 20 Relative Sea Level (cm) 10 0 -10 Amsterdam, Netherlands Brest, France Swinoujscie, Poland -20 1700 1750 1800 1850 1900 1950 2000 Adapted from IPCC SYR Figure 2-5
    243. 243. Changing Sea Levels 20 Global Temperature Change Relative Sea Level (cm) 10 0 -10 Amsterdam, Netherlands Brest, France Swinoujscie, Poland -20 1700 1750 1800 1850 1900 1950 2000 Adapted from IPCC SYR Figure 2-5
    244. 244. Sea Levels for 450,000 Years 20 31 SST (°C) Tropical Pacific 0 30 Sea Level (m) -20 29 -40 28 -60 -80 27 -100 26 -120 25 450 400 350 300 250 200 150 100 50 0 Time (KYBP)
    245. 245. Sea Levels for 450,000 Years 20 31 SST (°C) Tropical Pacific 0 30 Sea Level (m) -20 29 -40 28 -60 -80 27 -100 26 -120 25 450 400 350 300 250 200 150 100 50 0 Time (KYBP)
    246. 246. Sea Levels for 450,000 Years 20 31 SST (°C) Tropical Pacific 0 30 Sea Level (m) -20 29 -40 28 -60 -80 27 -100 26 -120 25 450 400 350 300 250 200 150 100 50 0 Time (KYBP)
    247. 247. Increase in Hurricanes?
    248. 248. Increase in Hurricanes? • Two studies showed the total number of hurricanes has not changed
    249. 249. Increase in Hurricanes? • Two studies showed the total number of hurricanes has not changed • However, the intensity of hurricanes has increased (more category 4 and 5 hurricanes and cyclones)
    250. 250. Increase in Hurricanes? • Two studies showed the total number of hurricanes has not changed • However, the intensity of hurricanes has increased (more category 4 and 5 hurricanes and cyclones) • Probably due to higher sea surface temperatures (more energy)
    251. 251. Increase in Hurricanes? • Two studies showed the total number of hurricanes has not changed • However, the intensity of hurricanes has increased (more category 4 and 5 hurricanes and cyclones) • Probably due to higher sea surface temperatures (more energy) • Difficult to know if this trend will continue
    252. 252. Increase in Hurricanes? 15 Data Unreliable SST/SPDI (meters3/sec2) 10 5 Scaled August-October Sea-Surface Temperature Adjusted Atlantic Storm Power Dissipation Index 0 1860 1880 1900 1920 1940 1960 1980 2000 2020
    253. 253. Increase in Hurricanes? 15 Data Unreliable SST/SPDI (meters3/sec2) 10 5 Scaled August-October Sea-Surface Temperature Adjusted Atlantic Storm Power Dissipation Index 0 1860 1880 1900 1920 1940 1960 1980 2000 2020
    254. 254. Increase in Hurricanes? 15 Data Unreliable SST/SPDI (meters3/sec2) 10 5 Scaled August-October Sea-Surface Temperature Adjusted Atlantic Storm Power Dissipation Index 0 1860 1880 1900 1920 1940 1960 1980 2000 2020
    255. 255. Increase in Hurricanes?
    256. 256. How Much Temperature Increase?
    257. 257. How Much Temperature Increase? • Some models propose up to 9°C increase this century
    258. 258. How Much Temperature Increase? • Some models propose up to 9°C increase this century • Two studies put the minimum at 1.5°C and maximum at 4.5°C or 6.2°C
    259. 259. How Much Temperature Increase? • Some models propose up to 9°C increase this century • Two studies put the minimum at 1.5°C and maximum at 4.5°C or 6.2°C • Another study puts the minimum at 2.5°C
    260. 260. Wildlife Effects
    261. 261. Wildlife Effects • Polar Bears
    262. 262. Wildlife Effects • Polar Bears  Require pack ice to live
    263. 263. Wildlife Effects • Polar Bears  Require pack ice to live  Might eventually go extinct in the wild
    264. 264. Wildlife Effects • Polar Bears  Require pack ice to live  Might eventually go extinct in the wild • Sea turtles
    265. 265. Wildlife Effects • Polar Bears  Require pack ice to live  Might eventually go extinct in the wild • Sea turtles  Breed on the same islands as their birth
    266. 266. Wildlife Effects • Polar Bears  Require pack ice to live  Might eventually go extinct in the wild • Sea turtles  Breed on the same islands as their birth  Could go extinct on some islands as beaches are flooded
    267. 267. Wildlife Effects • Polar Bears  Require pack ice to live  Might eventually go extinct in the wild • Sea turtles  Breed on the same islands as their birth  Could go extinct on some islands as beaches are flooded • Other species may go extinct as rainfall patterns change throughout the world
    268. 268. Effect on Humans
    269. 269. Effect on Humans • Fewer deaths from cold, more from heat
    270. 270. Effect on Humans • Fewer deaths from cold, more from heat • Decreased thermohaline circulation  Cooler temperatures in North Atlantic
    271. 271. Effect on Humans • Fewer deaths from cold, more from heat • Decreased thermohaline circulation  Cooler temperatures in North Atlantic • CO2 fertilization effect
    272. 272. Effect on Humans • Fewer deaths from cold, more from heat • Decreased thermohaline circulation  Cooler temperatures in North Atlantic • CO2 fertilization effect • Precipitation changes  Droughts and famine (some areas)  Expanded arable land in Canada, Soviet Union
    273. 273. Potential Worldwide Precipitation Changes -50 -20 -10 -5 5 10 20 50
    274. 274. Potential Worldwide Precipitation Changes -50 -20 -10 -5 5 10 20 50
    275. 275. Potential Worldwide Precipitation Changes -50 -20 -10 -5 5 10 20 50
    276. 276. Potential Worldwide Precipitation Changes -50 -20 -10 -5 5 10 20 50
    277. 277. Potential Worldwide Precipitation Changes -50 -20 -10 -5 5 10 20 50
    278. 278. Potential Worldwide Precipitation Changes -50 -20 -10 -5 5 10 20 50
    279. 279. Potential Worldwide Precipitation Changes -50 -20 -10 -5 5 10 20 50
    280. 280. Potential Worldwide Precipitation Changes -50 -20 -10 -5 5 10 20 50
    281. 281. Potential Worldwide Precipitation Changes -50 -20 -10 -5 5 10 20 50
    282. 282. Potential Worldwide Precipitation Changes -50 -20 -10 -5 5 10 20 50
    283. 283. Drought in Africa
    284. 284. Drought in Africa Lake Faguibine
    285. 285. Drought in Africa Lake Faguibine Lake Chad
    286. 286. Cost to Stabilize CO2 Concentrations 1800 Cost (Trillons U.S. Dollars) 1600 1400 1200 1000 800 600 400 200 0 450 550 650 750 Carbon Dioxide (ppm)
    287. 287. Cost to Stabilize CO2 Concentrations 1800 Cost (Trillons U.S. Dollars) 1600 1400 1200 1000 800 600 400 200 0 450 550 650 750 Carbon Dioxide (ppm)
    288. 288. Possible Solutions to Global Warming
    289. 289. Mitigation of Global Warming
    290. 290. Mitigation of Global Warming • Conservation
    291. 291. Mitigation of Global Warming • Conservation  Reduce energy needs
    292. 292. Mitigation of Global Warming • Conservation  Reduce energy needs
    293. 293. Mitigation of Global Warming • Conservation  Reduce energy needs  Recycling
    294. 294. Mitigation of Global Warming • Conservation  Reduce energy needs  Recycling • Alternate energy sources
    295. 295. Mitigation of Global Warming • Conservation  Reduce energy needs  Recycling • Alternate energy sources  Nuclear
    296. 296. Mitigation of Global Warming • Conservation  Reduce energy needs  Recycling • Alternate energy sources  Nuclear  Wind
    297. 297. Mitigation of Global Warming • Conservation  Reduce energy needs  Recycling • Alternate energy sources  Nuclear  Wind  Geothermal
    298. 298. Mitigation of Global Warming • Conservation  Reduce energy needs  Recycling • Alternate energy sources  Nuclear  Wind  Geothermal  Hydroelectric
    299. 299. Mitigation of Global Warming • Conservation  Reduce energy needs  Recycling • Alternate energy sources  Nuclear  Wind  Geothermal  Hydroelectric  Solar
    300. 300. Mitigation of Global Warming • Conservation  Reduce energy needs  Recycling • Alternate energy sources  Nuclear  Wind  Geothermal  Hydroelectric  Solar  Fusion?
    301. 301. Storage of CO2 in Geological Formations Adapted from IPCC SRCCS Figure TS-7
    302. 302. Storage of CO2 in Geological Formations 1. Depleted oil and gas reservoirs 1 Adapted from IPCC SRCCS Figure TS-7
    303. 303. Storage of CO2 in Geological Formations 1. Depleted oil and gas reservoirs 2. CO2 in enhanced oil and gas recovery 1 2 Adapted from IPCC SRCCS Figure TS-7
    304. 304. Storage of CO2 in Geological Formations 1. Depleted oil and gas reservoirs 2. CO2 in enhanced oil and gas recovery 3. Deep saline formations – (a) offshore (b) onshore 1 3a 2 Adapted from IPCC SRCCS Figure TS-7
    305. 305. Storage of CO2 in Geological Formations 1. Depleted oil and gas reservoirs 2. CO2 in enhanced oil and gas recovery 3. Deep saline formations – (a) offshore (b) onshore 3b 1 3a 2 Adapted from IPCC SRCCS Figure TS-7
    306. 306. Storage of CO2 in Geological Formations 1. Depleted oil and gas reservoirs 2. CO2 in enhanced oil and gas recovery 3. Deep saline formations – (a) offshore (b) onshore 4. CO2 in enhanced coal bed methane recovery 1 4 3b 3a 2 Adapted from IPCC SRCCS Figure TS-7
    307. 307. Global Warming Myths
    308. 308. Global Warming Has Stopped? 0.8 Δ Mean Temperature (°C) 0.6 0.4 0.2 0.0 -0.2 1975 1980 1985 1990 1995 2000 2005 2010 Year
    309. 309. Global Warming Has Stopped? 0.8 Δ Mean Temperature (°C) 0.6 0.4 0.2 0.0 -0.2 1975 1980 1985 1990 1995 2000 2005 2010 Year
    310. 310. Global Warming Has Stopped? 0.8 1366.8 1366.6 Δ Mean Temperature (°C) Solar Irradiance (W/m2) 0.6 1366.4 0.4 1366.2 1366.0 0.2 1365.8 1365.6 0.0 1365.4 -0.2 1365.2 1975 1980 1985 1990 1995 2000 2005 2010 Year
    311. 311. Global Warming Has Stopped? 0.8 1366.8 1366.6 Δ Mean Temperature (°C) Solar Irradiance (W/m2) 0.6 1366.4 0.4 1366.2 1366.0 0.2 1365.8 1365.6 0.0 1365.4 -0.2 1365.2 1975 1980 1985 1990 1995 2000 2005 2010 Year
    312. 312. Global Warming Has Stopped? 0.8 1366.8 1366.6 Δ Mean Temperature (°C) Solar Irradiance (W/m2) 0.6 1366.4 0.4 1366.2 1366.0 0.2 1365.8 1365.6 0.0 1365.4 -0.2 1365.2 1975 1980 1985 1990 1995 2000 2005 2010 Year
    1. A particular slide catching your eye?

      Clipping is a handy way to collect important slides you want to go back to later.

    ×