Week 3ES 101 Laboratory1Week 3 Lab ActivitiesAdiabat.docx

Week 3
ES 101 Laboratory
1
Week 3 Lab Activities
Adiabatic processes
Wind
Mid-latitude cyclones
Air pressure
2
It’s adiabatic
When heat is neither gained from, or lost to, the surrounding
air, the process is called adiabatic
If increase pressure, then parcel compresses and temperature
goes up even though didn’t add heat
If decrease pressure, then parcel expands and temperature goes
down even though didn’t remove heat
Pressure decreases as altitude increases
Adiabatic Processes Exercise: compute temperatures as air
parcel moves up over mountain and down other side
Explain results
Evaluate humidity changes and compute saturation mixing ratio
3
Wind

Draw wind flow arrows for upper atmosphere pressure map of
US
Upper atmosphere has no friction
Wind flow follows isobars and doesn’t cross them
Northern Hemisphere, so
High pressure is clockwise
Low pressure is counterclockwise
Draw wind flow arrows on surface pressure map of US
Friction plays role
Wind flow crosses isobars
Northern Hemisphere, so
High pressure is clockwise and winds diverge
Low pressure is counterclockwise and winds converge
4
Mid-latitude cyclones
Label main parts of mid-latitude cyclone for Northern
Hemisphere, including map and cross section, and answer
questions
Draw in frontal boundaries for two hypothetical weather maps
in the Northern Hemisphere and answer questions
5
Air Pressure
Interpret weather station symbols to read pressure and
temperature for various examples
Draw lines of constant surface air pressure on a U.S. weather
map at selected intervals as specified
6

Remember
To do your Moodle quiz by 11:55 pm on Saturday night
To do your Environmental Events Log by 11:55 pm on Saturday
night
Review completed lab for next week’s quiz
Read chapters for next week
7
Visualizing Physical Geography
Copyright © 2012 John Wiley & Sons, Inc.
Chapter 4
Atmospheric Moisture and Precipitation
by Timothy Foresman & Alan Strahler
© Daniel Berehulak/Getty Images
1
Chapter Overview
Water and the Hydrosphere
Humidity
Adiabatic Processes
Clouds and Fog
Precipitation

Human Impacts on Clouds and Precipitation
© Daniel Berehulak/Getty Images
2
The Three States of Water
Solid (ice)
Liquid (water)
Gas (water vapor)
Latent heat is transferred when water changes states
Release of energy occurs when...
Absorption of energy occurs when…
© John Wiley & Sons, Inc.
3
The Three States of Water
Evaporation
Freezing
Condensation

Sublimation
Deposition (e.g., Frost)
On a cold, dry day, snow covering a sidewalk slowly
disappears, and there is no visible melting. Which process is at
work?
a. sublimation
b. deposition
c. condensation
d. evaporation?
4
The Hydrosphere
The total water realm of the Earth’s surface, including the
oceans (97.5%) and freshwater (2.5%).
Freshwater includes glaciers (68.7%), ground water (30%),
permafrost (0.8%), and the surface waters of the lands and
water held in the atmosphere make up 0.4%.
5

The Hydrosphere
Oceans
Ice sheets and glaciers
Surface water
©John Wiley & Sons, Inc.
© NG Image Collection
6
The Hydrosphere
The small blue sphere represents the planet’s total water volume
in proportion to the Earth’s size, demonstrating the limits on
this critical resource
© SPL/Photo Researchers
7

The Hydrologic Cycle
Water moves among the ocean, atmosphere and land
Evaporation
Precipitation
Transpiration
Evapotranspiration
Runoff
Sinks into soil
Recharge of groundwater
8
Humidity
The amount of water vapor in the air
The maximum volume of water vapor, or humidity, of a mass of
air increases sharply with rising temperature
Air at room temperature (20°C [68°F]) can hold about three
times as much water vapor as freezing air (0°C [32°F])

9
Humidity
The low humidity of Death Valley in California creates a warm
but comfortable day for a trek across the sand
High-humidity conditions of a Florida wetland, the same
temperature reading can be unbearably hot
10
Relative Humidity (RH)
Compares the amount of water vapor present to the maximum
amount that the air can hold at that temperature
Expressed as a percentage
Air holding ½ its capacity has a RH of 50%
Can change in two ways:
Gain or lose moisture
Change in temperature

11
Specific Humidity
The actual amount of water vapor held by a parcel of air (g/kg)
When air cools, capacity is reduced
When air warms, capacity increases
Specific humidity and temperature values are high at low
latitudes
Specific humidity values fall as temperature in high latitude
regions
12
Specific Humidity
© John Wiley & Sons, Inc
13

Dew Point
The temperature at which air with a given humidity will reach
saturation when cooled without changing its pressure
Dew
Frost
What happens as air is cooled below the dew-point temperature
at temperatures above freezing?
14
Adiabatic Processes
As a parcel of air is lifted, atmospheric pressure becomes lower,
and the parcel expands and cools
As air cools to the dew point, clouds form
As air descends, air is compressed and warms
Adiabatic processes = process in which the temperature of a
parcel of air changes in responses to a change in atmospheric
pressure
15

Adiabatic Processes
The Dry Adiabatic Lapse Rate
The rate at which rising air cools or descending air warms when
no condensation is occurring
10°C per 1000 m
5.5°F per 1000 ft
© A. N. Strahler
16
Adiabatic Processes
The Moist Adiabatic Lapse Rate
The rate at which rising air is cooled by expansion when
condensation is occurring; ranges from:
4 to 9°C per 1000 m
2.2 to 4.9°F per 1000 ft
© A. N. Strahler
17

Adiabatic Processes
© A. N. Strahler
18
Adiabatic Processes
1. Suppose the air parcel shown contained more water vapor.
How would that affect the lifting condensation level?
2. What would be the effect if there were less water vapor in the
air parcel?
© A. N. Strahler
19
Clouds and Fog
Clouds consist of water droplets, ice crystals, or both
Condensation nucleus = a tiny bit of solid matter (aerosol) in
the atmosphere, on which water vapor condenses to form a tiny
water droplet

20
Clouds and Fog
Clouds Classification by Height
Cloud Families: High clouds, middle clouds, low clouds, clouds
of vertical development
© A. N. Strahler
21
Clouds and Fog
Cirroform clouds = at the top of the troposphere, these clouds
are high, thin, wispy clouds drawn out into streaks. They are
composed of ice crystals and form when moisture is present
high in the air
Cirrus Clouds
22

Clouds and Fog
Stratiform clouds = are blanket-like layers that cover large
areas. A common type is stratus clouds, which often cover the
entire sky. In this photo, high cumulus clouds (left) grade into a
high stratus layer (right).
Stratiform Clouds
23
Clouds and Fog
Cumuliform clouds = globular masses of cloud that are
associated with small to large parcels of moist rising air. In this
photo, puffy, fair-weather cumulus clouds drift over a lake.
Cumulus Clouds
24
Clouds and Fog
Nimbus clouds = are clouds of any of type that produce

precipitation. An isolated cumulonimbus cell discharges
its water volume as precipitation in this photo.
Cumulonimbus Clouds
25
Clouds and Fog
Fog
Radiation fog: formed when temperature of the air at ground
level falls below dew point
Advection fog: forms when warm moist air moves over a cold
surface
Common over oceans (“sea fog”)
West Coast of US and Canada
26
Precipitation

Types of Precipitation
Rain
Snow
Hail
Ice storm
27
Precipitation
Annual rates of precipitation vary greatly around the world
Tropical regions
Wet-dry regions
Deserts
Equatorial regions

28
Precipitation
Globally, rainfall ranges from tropical to desert to polar
This profoundly influence landforms, the biosphere, and human
activities
Most species have evolved to survive within narrow ranges of
annual precipitation
Tropical regions
Deserts
29
Precipitation
Precipitation forms in clouds by two different processes:
Warm Cloud = Collision Coalescence
Cold Cloud = Ice crystal process

Warm cloud shown above = Formation of precipitation through
coalescence of water droplets
30
Precipitation
Review Figure 4.10 and answer this question. Which type of
cloud is represented in this figure?
a. cirrus
b. altostratus
c. cumulonimbus
d. cirrostratus

31
Precipitation
Cold Cloud = Ice crystal process
Precipitation forms as water vapor evaporates from super cooled
liquid cloud drops. The water vapor is then deposited on ice
crystals, forming snowflakes
32
Precipitation
Rain and snow
Freezing rain

Measuring Precipitation = U.S. National Weather Service’s
NEXRAD (Next Generation Radar)
Courtesy NOAA
Courtesy NOAA
33
Precipitation
Hail can form during thunderstorms when there are strong
updrafts
34
Precipitation
Atmospheric Lifting
Air can move upward in four ways: through orographic,
convective, frontal, or convergent lifting
35

Precipitation
Atmospheric Lifting
Orographic precipitation = Precipitation that is induced when
moist air is forced vertically over a mountain barrier
Convective precipitation = Precipitation that is induced when
warm, moist air is heated at the ground surface, rises, cools, and
condenses to form water droplets, raindrops, and eventually
rainfall
36
Precipitation
Orographic Lifting
37

Precipitation
Convective Lifting
38
Precipitation
Convective Lifting
If the environmental lapse rate increased (that is, if it were
cooler at higher altitudes), how would the lifting condensation
level change?
a. It would be higher.
b. It would be lower.
c. It would stay the same.
d. It is impossible to determine.
39
Precipitation
Convergent Lifting

40
Precipitation
Frontal Lifting
41
Acid Rain
Also called acid deposition
made up of raindrops that have been chemically acidified by
industrial air pollutants such as sulfur dioxide (SO2) and nitric
oxide (NO2)
Acids have a low pH value, less than that of distilled water (pH
= 7)
The lower the pH value, the more acidic the liquid.
Acidity of rainwater in U.S., 2005
© Illinois State Water Survey

42
Effects of Acid Rain
Acid streams and lakes affect aquatic life
Damage to forests
Damage to soils
Damage to buildings
Consider the pattern of acid rain deposition in the northeastern
United States. What is the implication for international
relations?
© Gerd Ludwig/INSTITUTE
43
Cloud Cover, Precipitation, and Global Warming
Clouds: Longwave warming or shortwave cooling?

Increased Precipitation?
Any rise in sea-surface temperature will increase the rate of
evaporation, and an increase in evaporation will raise the
average atmospheric content of water vapor. What effect will
this have on climate?
© NASA Images
44
Chapter 5
Global Atmospheric and Oceanic Circulation
by Timothy Foresman & Alan Strahler
1
Chapter Overview
Atmospheric Pressure
Wind Speed and Direction
Global Wind and Pressure Patterns
Local Winds

Oceanic Circulation
2
Copyright © 2008 John Wiley and Sons Publishers Inc.
Atmospheric pressure is pressure exerted by the atmosphere
because of the force of gravity acting on the overlying column
of air.
Measuring Atmospheric Pressure
Units = inches of mercury (in. Hg) or millibars (mb).
Standard sea level pressure = 1013.2 mb.
Cold, clear night pressure > 1013.2 mb.
Center of a storm with rising warm air will have a pressure <
1013.2 mb.
Barometer is an instrument that measures atmospheric pressure.
© John Wiley & Sons ,Inc
Measuring Atmospheric Pressure
Radiosonde (balloon) is launched twice a day at key locations in
United States
Radiosondes measure:

Pressure
Altitude
GPS location
Temperature
Relative humidity
Wind speed and direction
Would one expect low or higher than standard sea level pressure
in a hurricane?
4
Atmospheric Pressure and Altitude
Air density depends on pressure and temperature.
Atmospheric pressure decreases with altitude.
Wind:
Horizontal movement of air
Renewable resource
Measured with an anemometer

Wind direction:
Identified by the direction from
which the wind comes
West wind blows from west to east
Measured with a wind vane
Wind speed and direction are determined by three factors:
pressure gradient, Coriolis effect, and friction.
Courtesy Taylor Instrument Company and
Wards Natural Science Establishment
Pressure Gradients
Change of atmospheric pressure measured along a line at right
angles to the isobars.
Pressure gradient goes from high to low pressure.
7
Pressure Gradients

Isobar = line on a map drawn through all points having the same
atmospheric pressure
Closely spaced
Where would you find the greatest pressure gradient on this
map?
a. Oklahoma City
b. Southwestern Missouri
c. Memphis
d. Nashville
8
Pressure Gradients
Unequal heating of the Earth’s surface leads to a pressure
gradient and causes wind.
Latitude, terrain differences, and land cover can cause uneven
heating, pressure gradients and wind.
1
2
3
9

Pressure Gradients
If the island were in the Arctic and covered by glacial ice,
would the pressure gradient be the same or different?
10
The Coriolis Effect (CE)
An effect of the Earth’s rotation that acts like a force to deflect
a moving object on the Earth’s surface to the:
Right in the northern hemisphere
Left in the southern hemisphere
11
The Coriolis Effect (CE)

Due to Earth’s rotation, a path from the North Pole to New York
along 74°W meridian would curve to the right, toward Chicago.
12
Geostrophic wind is wind at high levels (upper levels) above the
Earth’s surface moving parallel to the isobars, at a right angle
to the pressure gradient.
13
The Frictional Force (FF)
Force exerted by the ground surface that is proportional to the
wind speed
Always acts in the opposite direction to the direction of motion
Greatest closest to the surface

14
The Frictional Force
A cyclone is a center of low pressure where surface air
converges into a spiral and is uplifted to the upper troposphere.
The PGF, CE, and FF cause the surface wind to spiral,
converging inward toward the low-pressure center.
As the inward motion converges, it forces the air to rise (uplift)
The Frictional Force
An anticyclone is a center of high pressure where upper
troposphere winds spins downward (subsidence) and diverges
outward at the surface.

precipitation
Global surface winds on an ideal Earth (see Figure 5.11):
Surface winds are shown on the disk of the Earth, and the cross
section at the right shows winds aloft.
17

Tropical Circulation
Warm air over the equator rises and forms low pressure
resulting in the equatorial trough (wet weather).
Trade winds converge at the equator.
Air descends near 25 to 30o latitude forming a subtropical high
pressure (dry weather) zone.
Hadley cell = A low-latitude atmospheric circulation cell with
rising air over the equatorial trough and sinking air over the
subtropical high-pressure belts.
19
Intertropical Convergence Zone (ITCZ):
A zone of convergence of air masses along the equatorial trough
Doldrums
ITCZ shifts with the seasons following the zone of highest

insolation:
Over the ocean it shifts a few degrees between January and
July.
Over land, the zone shifts 20o to as much as 40o in Asia.
Monsoon = seasonal reversal of the wind
January = north wind (dry)
July = warm, moist air (wet)
21
Considering the direction of the winds compared to the isobars,
which statement is most correct?
Because this area is near
the equator, the Coriolis effect

has no influence on these winds.
Because the pressure gradients
are great, friction has no
influence on these winds.
Because some of the winds are over the ocean, neither the
Coriolis effect nor friction has an influence on these winds.
Because the alignment of the wind direction is at 45°to the
isobars, both the Coriolis effect and friction are important.
22
North American monsoon
© Ralph Lauer/Zuma Press/NewsCom
23

Area of high atmospheric pressure centered at about 30° N and
30° S
Stable and dry weather
Trade winds and westerlies
Hawaiian and Azores high
Shift with the seasons
East and west coast differences
Subtropical high-pressure cells
© A. N. Strahler
In the days of sailing ships, which pattern of navigation made
the most sense, considering prevailing wind directions?
a. United States to Africa to England back to the United States
b. United States to England to Africa back to the United States
c. United States to England back to the United States
d. United States to Africa back to the United States
© A. N. Strahler
25

Midlatitude Circulation
Westerlies
Between about 30° and 60° latitude
Polar front = boundary between cold polar air masses and warm
subtropical air masses
26
Midlatitude Circulation
Jet stream = high-speed airflow in a narrow band within the
upper-air westerlies and along certain other global latitude
zones at high altitudes:
Polar-front jet stream
Shifts equatorward in the winter
Subtropical jet stream
27
What a Geographer Sees

Jet Streams and Air Travel
If an airplane flying in the center of this subtropical jet stream
travels east at 1000 km/hr (621 mi/hr), how fast will the same
airplane go, with the same fuel expenditure, when it travels
west in the jet stream on its return flight?
Courtesy NASA
28
Jet stream disturbances
Rossby waves
Baroclinic instability
Zonal flow (west to east)
29

Jet stream disturbances
Growth of disturbances in the jet stream
30
High-Latitude Circulation
January
July
Courtesy John E. Oliver
31

Global Circulation at Higher Altitudes
32
Global surface winds on an ideal Earth (Review)
33
Global air cells: Ferrel, Hadley, or Polar? (Review)

34
Local Winds
Daily Cycles of Winds
Daily reversal of the winds as a result of uneven heating
Sea breeze
Land breeze
35
Local Winds
Daily Cycles of Winds
Mountain breeze
Valley breeze

36
Local Winds
Other Topographic Winds
Chinook: a dry wind
Santa Ana winds
For north–south mountain ranges in midlatitude regions (30° to
45° latitude), dry regions will be found on the ____ side in the
northern hemisphere and on the ____ in the southern
hemisphere.
a. east; east
b. west; west
c. east; west
d. west; east
© A. N. Strahler
37

Local Winds
Other Topographic Winds
Santa Ana winds can create fire hazards. In this photo, wildfires
have already begun in some areas, as is apparent from the
smoke drifting off the Southern California coast.
Courtesy NOAA
Oceanic Circulation
Ocean Currents
A persistent, dominantly horizontal flow of water controlled by
wind patterns
Gyres: large circular ocean movements
What relationship do you notice with the northern hemisphere
ocean current and the pressure type typically located at 30o N?
39
Oceanic Circulation
Ocean Currents
Ocean circulation and energy transport:
Warm surface waters in the tropics move poleward.
Thermohaline circulation: Cold and dense waters in the N.
Atlantic sink, flow equatorward, and eventually upwell to the

surface at far distant locations to cool surrounding regions and
complete the circuit.
© NG Maps
40
Oceanic Circulation
Circulation and Energy Transfer
Energy surplus
Energy deficit
In order to maintain the Earth’s energy balance, absorbed solar
energy is moved from regions of excess to regions of deficit,
carried by ocean currents and atmospheric circulation
41
Oceanic Circulation
Cycles in Atmospheric and Oceanic Circulation
El Niño–Southern Oscillation (ENSO)
La Niña
© NG Maps

© NG Maps
42
Oceanic Circulation
Climate effects of El Niño events
43
Oceanic Circulation
North Atlantic Oscillation (NAO)
Pacific Decadal Oscillation (PDO)
© NG Maps
© NG Maps
44

Week 3ES 101 Laboratory1Week 3 Lab ActivitiesAdiabat.docx

Week 3ES 101 Laboratory1Week 3 Lab ActivitiesAdiabat.docx

More Related Content

Similar to Week 3ES 101 Laboratory1Week 3 Lab ActivitiesAdiabat.docx

More from melbruce90096

Recently uploaded

Week 3ES 101 Laboratory1Week 3 Lab ActivitiesAdiabat.docx