- Changes in Temperature since 1880 - Natural (Physical) Factors

1. 1
Chapter
Gateway 2

2. 2

3. 3
Irregular but SIGNIFICANT INCREASE

4. 4
Global climate change refers to the variation in the
global climate or climatic patterns in the long term.
Includes major changes in:
• Temperature
• Precipitation
• Wind patterns

5. 5
Changes in Global Temperatures since 1880

6. 6

7. 7
Describe the changes in global temperatures
between 1880 and 2011. [4]

8. 8
Generally, from 1880 to 2011, global temperatures experienced fluctuations but
increased significantly.
 It increased from 13.7°C in 1880 to 14.5°C in 2011.
 Within the 131 years, temperatures increased by 0.8°C.
From 1880 to 1980,
 temperatures increased gradually from 13.7°C to 14.1°C.
 Within 100 years, temperatures increased gradually by 0.4°C.
However, from 1980 to 2011,
 the increase of 0.4°C took only 31 years.
 temperatures increased rapidly from 14.1°C to 14.5°C within just 31
years.
Describe the changes in global temperatures
between 1880 and 2011. [4]

9. 9
10 of the warmest years that were recorded between
1850 and 2010
Rank Year Rank Year
1 2010 6 2006
2 2005 7 2009
3 1998 8 2007
4 2003 9 2004
5 2002 10 2001
What is one prominent observation you can make?
• 10 of the warmest years occurred between 1990 to 2010.
• 9 out of 10 were recorded in the recent decade (between 2000 to
2010).

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What is causing all
these temperature changes?
Natural
causes
Human
causes
1) Variations in Solar Output
(Sunspot activity)
2) Volcanic Eruptions
(Temporary global cooling)
1) Deforestation
2) Changing land use
3) Agriculture
4) Industries
5) Urbanisation

11. They are cooler regions on the Sun’s surface.
A big sunspot:
3700˚C
Surrounding
surface of sun:
5500˚C
1) Sun Spot Activity (Handout pg. 3 / TB pg. 100)
11
Watch Rotation of Sun
Sunspots appear as dark
spots on the Sun’s surface
https://www.spaceweatherlive.com/en/help/what-are-sunspots

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Movement of charged
particles
- Convection currents
- Rotation of sun
(Coriolis Force)
Changes
in Sun’s
magnetic field
Sun emit varying amounts
of solar radiation
Affects earth’s climate
More solar radiation =
Increase in global temp
Creates
magnetic
fields
1) Sun Spot Activity (Handout pg. 3 / TB pg. 100)

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Explain Sunspots:
1) Sunspots are cooler regions on the sun’s surface that appear as
dark spots.
2) Intense solar magnetic activity  number of sunspots increases
 causes higher solar radiation.
3) Areas surrounding the sunspots radiate more energy to
compensate for lower temperatures of the sunspot areas.
4) Higher sunspot activity  higher amount of solar radiation
received by earth  coincides with higher global temperatures.
1) Sun Spot Activity (Handout pg. 3 / TB pg. 100)

14. Temp
change
14
With reference to Fig. 2, describe and explain the relationship between
sunspot activity and the earth’s surface temperatures since 1900. [4]
1) Sun Spot Activity (Handout pg. 3 / TB pg. 100)

15. 15

16. 16
With reference to Fig. 2, describe and explain the relationship between
sunspot activity and the earth’s surface temperatures since 1900. [4]
1) Sun Spot Activity (Handout pg. 3 / TB pg. 100)
Describe relationship:
• There is a positive relationship between sunspot activity and the earth’s surface
temperatures.
• From 1900 to 1990, when sunspot activity increased from 75 to 190 spot counts,
earth’s surface temperatures increased by 0.3°C.
Explain relationship:
• When there is a higher number of sun spots  the areas surrounding the
sunspots would radiate more energy to compensate for the lower temperatures
of the sunspot areas.
• This would cause higher solar radiation  leading to more solar radiation
received by earth  cause rise in earth’s temperatures.

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2. Volcanic Eruptions (Handout pg. 4 / TB pg. 100-105)

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2. Volcanic Eruptions (Handout pg. 4 / TB pg. 100-105)
Highlight/underline your article:
• What was being ejected into the atmosphere during the eruption?
• What happens to the materials that is ejected into the atmosphere?
• How did the eruption cause global cooling?
• How did the eruption affect rainfall?

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2. Volcanic Eruptions (Handout pg. 4 / TB pg. 100-105)

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2. Volcanic Eruptions (Handout pg. 4 / TB pg. 100-105)
Explain volcanic eruptions:
1) Large volumes of carbon dioxide, water vapour, sulphur dioxide,
dust and ash are released into the atmosphere.
2) Sulfur dioxide reacts with water  forms sulphur based
particles in the atmosphere.
3) Together with dust and ash particles, the sulphur based particles
reflect solar energy back into space.
4) Lesser solar energy reaches earth’s surface  cooling influence
on regional and global temperatures (temporary)

21. 21
2. Volcanic Eruptions (Pitstop 6)
Mount Pinatubo eruption in 1991 – Spread of sulfur dioxide across the earth

22. 22
The Greenhouse Gases (TB pg 102)
Video_What Is Greenhouse Gas

23. 23
Natural
Greenhouse Effect
Natural
emission
of GHG
TB pg. 102
NATURAL vs Enhanced
Greenhouse Effect

24. 24
Natural Greenhouse Effect
(Handout pg 5 / TB pg.102)
Sun
Atmosphere
1. Incoming shortwave radiation from the sun
passes through the GHG found in the
atmosphere.
Earth’s Surface

25. 25
Sun
Atmosphere
2. Some of the
shortwave
radiation from the
sun is reflected by
the earth & the
atmosphere.
Earth’s Surface
Natural Greenhouse Effect
(Handout pg 5 / TB pg.102)

26. 26
Sun
Atmosphere
3. Most of the shortwave radiation
from the sun is absorbed by the
earth’s surface.
Earth’s Surface
Natural Greenhouse Effect
(Handout pg 5 / TB pg.102)

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Sun
Atmosphere
4. The earth’s surface warms up
and emits longwave radiation
to the atmosphere.
Earth’s Surface
Natural Greenhouse Effect
(Handout pg 5 / TB pg.102)

28. 28
Sun
Earth’s Surface
Atmosphere
5. Greenhouse
gases absorb
longwave
radiation, thus
warming the
atmosphere.
Natural Greenhouse Effect
(Handout pg 5 / TB pg.102)

29. 29
_____
____________ _______
_____________
1. Incoming shortwave radiation from the sun passes through the
GHG found in the atmosphere.
2. Some of the shortwave radiation from the sun is reflected by the
earth & the atmosphere.
3. Most of the shortwave radiation from the sun is absorbed by the earth’s surface.
4. The earth’s surface warms up and emits longwave radiation to the atmosphere.
5. Greenhouse gases absorb longwave radiation, thus warming the atmosphere.
Natural Greenhouse Effect
(Handout pg 5 / TB pg.102)

30. Sun
Earth’s SurfaceAtmosphere
1) Incoming shortwave
radiation from the sun
passes through the GHG
found in the atmosphere.2) Some of the shortwave
radiation is reflected by
the earth and the
atmosphere. Some heat
escapes back to space.
3) Most of the shortwave
radiation from the sun is
absorbed by the earth’s surface.
4) The earth’s surface warms up
and emits longwave radiation to
the atmosphere.
GHG
5) Greenhouse gases in the atmosphere
absorb the longwave radiation, thus
warming earth’s atmosphere.
Natural Greenhouse Effect
(Handout pg 5 / TB pg.102)

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Too much
GHG emitted
Natural
emission
of GHG
(Human) Enhanced
Greenhouse Effect
TB pg. 103
Natural vs ENHANCED
Greenhouse Effect

32. 32
Sun
Earth’s Surface
Atmosphere
5. More greenhouse gases absorb
more longwave radiation, thus
warming the atmosphere at a far
greater rate than the natural
emissions of greenhouse gases.
Enhanced Greenhouse Effect
(Handout pg 5 / TB pg.103)

33. Sun
Earth’s SurfaceAtmosphere
1) Incoming shortwave
radiation from the sun
passes through the GHG
found in the atmosphere.
2) Some of the shortwave
radiation is reflected by the
earth and the atmosphere.
LESS heat escapes back to space.
3) Most of the shortwave
radiation from the sun is
absorbed by the earth’s surface.
4) The earth’s surface warms up
and emits longwave radiation to
the atmosphere.
GHG
5) HIGHER concentration of greenhouse
gases in the atmosphere absorb MORE
longwave radiation, thus warming earth’s
atmosphere rapidly. This leads to a rise in
global temperatures and global warming.
Enhanced Greenhouse Effect
(Handout pg 5 / TB pg.103)

34. 34

35. 35

36. 36
Guiding questions:
1) Recall: What does greenhouse gases do?
2) What happens when there are too many of them in our
atmosphere?
3) What happens to the amount of longwave radiation
absorbed by earth?
4) In turn, how does this affect the temperature of the earth?
* How should my arrows be drawn on my diagram?*
How does this increase
in GHG affect the
greenhouse effect?

37. 37
Natural vs Enhanced
Greenhouse Effect (Summary)
Too much
GHG emitted
Natural
emission
of GHG
Too little
GHG
Causes a greater rate of
increase in earth’s temperature
Important for keeping earth’s
atmosphere warm to sustain life

38. 38Video_Global Warming 101

39. Summary of what we’ve learnt so far…
Natural/Physical Factors Human/Anthropogenic Factors
Write down three things that you have learnt
1. Since 1880, global temperatures have experienced
an irregular but SIGNIFICANT INCREASE.
2. Causes of Climate Change:

40. Summary of what we’ve learnt so far…
Natural/Physical Factors Human/Anthropogenic Factors
a) Variations in Solar Output
b) Volcanic eruptions
a) Burning of fossil fuels
b) Deforestation
c) Changing land uses
 Agriculture
 Industries
 Urbanisation
Write down three things that you have learnt
2. Causes of Climate Change:
• Causes greenhouse gases to be released at a far greater rate
•  Enhanced greenhouse effect
• More GHG  more longwave radiation absorbed
•  warm the atmosphere  Global warming