1. Chapter 2
Gateway 2
What is
happening to
the Earth’s
climate?

2. Global Climate Change
• The variation in global climate
• Changes in the climatic patterns in the long
term
• General trend has been an irregular but
significant increase in global temperature.

3. Global Warming
• Process where
global
temperatures
increase over a
long period of
time.

4. Global Cooling
• Process where global
temperature decrease
over a long period of
time.

5. Changes since 1880
•
•
•
•
Drastic fluctuations on annual basis.
5-year mean still fluctuates.
Over 120 years, mean has risen significantly.
Increase in temperature is more obvious in
Africa, Parts of Asia and the Arctic.

6. Natural Causes of Climate Change
• There are some natural
phenomena that will cause
climate change.
1. Variations in Solar Output
2. Volcanic Eruptions

7. Variations in Solar Output
• Solar radiation changes as the magnetic field
of the sun changes.
• Increase in magnetic activity will lead to
increase in solar radiation.
• Sunspot activity leads to more solar radiation
emitted.
• Solar activity cycle is linked with earth’s cycle
of high and low global temperature.
– High activity leads to spikes in temperature.

8. What are Sunspots?

9. Volcanic Eruptions
• During eruptions, cabon dioxide, water
vapour, sulphur dioxide, dust and ash are
released into the environment.
• Sulphur dioxide reacts with water to form
sulphur-based particles in the atmosphere.
• These work with the dust and ash to reflect
solar energy back into space, causing global
dimming.

10. Global Dimming
• The gradual reduction in the amount of
sunlight reaching the earth’s surface.
• Causes temporary cooling of the earth.
• Eruption of Mt Pinatubo, 1991, lead to
lowering of temperatures in the northern
hemisphere by as much as 0.6°C.
• Effect can last several years.

11. Greenhouse Effect

12. What is greenhouse effect?
• Process that sustains habitable temperature
on earth.
• Shortwave radiation from the sun reaches
earth as visible light.
• Longwave radiation is heat from the heated
surface of the earth.
– Earth’s surface is heated by the shortwave
radiation from the sun.

13. Process of greenhouse effect
• Shortwave radiation comes from the sun.
• Some of it is reflected and trapped in the
atmosphere by greenhouse gases.
• Some of it passes through and heats up the earth’s
surface.
• The earth’s heated surface emits (gives off) longwave
radiation.
• Some longwave radiation is reflected back by the
atmosphere layer while some escapes.
• The reflected radiation continues to heat up the
earth’s surface.
• This maintains the optimal temperatures on earth for
life to exist.

14. What is enhanced greenhouse effect?
• When greenhouse gases in the atmosphere
increase, the amount of radiation trapped
increases.
• This causes the heat on Earth’s surface to
increase.
• Key greenhouse gases are nitrous oxide (N2O),
carbon dioxide (CO2) and methane (CH4).

15. Who causes this spike?
Burning of Fossil Fuels
• Industries and modern fossil-fuel burning
machines have accounted for the spike in
greenhouse gases.
• Intense spike in all 3 tracked gases since 1500
to date (due to the onset of the Industrial
Revolution and rapid human population
growth)

16. Deforestation
• Loss of forests due to removal and clearance
of tress.
• Commercial value of timber
• Enhance need for agricultural / residential /
commercial land
• Loss of carbon lungs of the earth.
• South America and Southeast Asia are the 2
highest areas of forest loss.

17. Reforestation
• Process where trees are planted to replace
lost forest areas.
• China, India, Vietnam, USA has large scale
reforestation programs.
– When you need to reforest it means that you had
previously done deforestation.
– Reforestation levels often fall short of
deforestation levels.
– Reforestation also tends to be of lesser variety
compared to the original lost species.

18. Changing land use
Agriculture
• Global increase in meat consumption leads to
increased livestocks reared.
• Argentina is one of the world’s largest beef
producers.
• Methane gas emitted from lifestock account for
30% of Argentina’s total greenhouse gas
emissions.
• Widespread use of machines in agriculture
release additional CO2 into the atmosphere.

21. Industries
• Production of goods and services.
• Secondary Industries are in manufacturing.
– Conversion of fossil fuels.
– Production of greenhouse gases as by-products
• Some processes or products have greater
emissions.
• Carbon Dioxide emissions the key indicator of
Industries.
– Emerging economies contribute more due to rapid
emissions.

23. Urbanisation
• Process where more people live in urban
areas.
• Widespread use of Fossil Fuels for energy.
• High concentration of cars, buses and other
transportation.
• Large emission of greenhouse gases.

25. Impact of Climate Change
• Changes in global climate impact humans.
• Small temperature changes can lead to sea
level rising.
• Melting of glacial and polar ice results in larger
volume of water in the sea.
• Frequent extreme weather events and boom
in insects cause spread of disease.
• In certain regions, growing season might
lenghten.

26. Sea Level Rise
• Increase in the mean height of the sea’s
surface.
• High negative impact to humans living near
coastal areas.
• 2/3 of the world’s largest cities located in
coastal areas are at risk due to rising sea level.
• Island nations are especially at risk.

28. More Frequent Extreme Weather
• Extreme weather event is a severe and rare
weather phenomenon that leads to significant
economic losses and loss of lives.
• Extreme weather events have increased in the
past decades.
• Rise in surface temperatures lead to
disruption of the hydrological cycle.

29. • Increase in water vapour and latent heat
causes a warmer atmosphere.
• Warmer atmosphere conducive to extreme
weather events.
• Super tornadoes; Massive droughts.

30. Spread of infectious insect-borne diseases
• Climate change leads to increase
temperatures and rainfall in some areas.
• Insects thrive in these conditions.
• Insect-borne diseases will spike.
– Malaria and Dengue are spread by
mosquitoes that increase due to higher
rainfall, leading to more stagnant water
gathering.
– Warming up of temperate areas also lead
to change in disease profiles.

31. Lengthening the growing season
• In certain areas, rise in temperature
brings benefits.
• Previously cold periods stay warmer.
• Growing season is extended as a
result.
• Good for crops that require higher
temperatures

32. Shortening of growing season
• Temperate crops
• Require cool climate to grow effectively.
• Rise in temperature leads to shortening
of growing season.
• Apples, Cherries, Strawberries.

34. Responses to Climate Change
• International Level Responses
– Kyoto Protocol
– Copenhagen Conference
• National Level Responses
– Singapore Green Plan
– Green Mark Scheme Singapore
– Energy Labelling Programme India
– The Indian Network of Climate Change
Assessment (INCCA)

35. International Responses
Kyoto Protocol 1997
• Agreement to reduce greenhouse gases
emission levels
• Developed countries had greater
responsibility on reducing greenhouse
gas
• Not all nations in the United Nations
signed the protocol.

36. Kyoto Protocol Successes
• Many countries met targets set
– Greece, Finland, Ireland, etc
• Successfully encouraged the
development of sustainable
development
• Countries earned carbon credits by
helping developing countries develop
sustainably.

37. Kyoto Protocol Limitations
• Not all countries met targets.
• No compulsion to help developing
countries develop sustainably.
• Countries that did not sign continue
to contribute significantly to global
emissions.

38. Home / BYOD Task
• Go online and search for the following
information.
1.
2.
What is the difference between countries
signing the Kyoto protocol and those that
ratified it?
Which country(s) have not signed the
protocol and which ones have not ratified
it?
• Complete the handout and submit it the
next lesson.

39. Copenhagen Conference 2009
• Discussion of issue of climate change
coping measures by important political
figures.
• Copenhagen Accord drafted.
• Long-term goal of keeping increases in
global mean maximum temperature to
within 2°C of global temperatures before
1850.

40. Copenhagen Accord Success
• Successfully setting of targets for greenhouse
gas emissions
• Developed countries committed to reduction
by 2020.
• Provision of US$30Billion to aid LDCs between
2010-2012.
• Long term aid of US$100Billion a year by
2020.

41. Copenhagen Accord Limitations
• Greenhouse gas reduction targets unable
to create the desired temperature
reduction.
• No concrete plans on how to reduce
greenhouse gas emissions.
• Many Developed countries refused to
sign.
• Targets are taken as guidelines, many
countries do not adhere.

42. Why is it so difficult
to get countries to
adhere to the
Copenhagen Accord?
What could be more
important than the
Earth?

43. National Level Responses
• Policies that individual countries
implement.
• Work towards the international goal of
reducing greenhouse gas emissions.
• Each country has different economies
and issues so their national level
responses will be different.

44. Singapore
Pg
115116
1. Singapore Green Plan 2012
2. Green Mark Scheme
3. Plant-A-Tree programme
4. National Urban Transport Policy
(NUTP)

45. India
Pg
117
1. Energy Labelling Programme
2. The Indian Network of Climate
Change Assessment (INCCA)

46. Possible Question
“Explain with the aid of
examples you have studied, why
national level responses to
climate change are important
and how they may or may not
be effective.” [8m]

47. How to answer?
• 1m for the difference between International
and National level responses.
• 1m for purpose of National Level response
• 1m for Describing the 1st example.
• 1m for the Successes of 1st example
10 mins
Try it!
• 1m for the Limitations of 1st example
Use the
info in
• 1m for Describing the 2nd example.
your
textbook
• 1m for the Successes of 2nd example
• 1m for the Limitations of 2nd example

48. Homework
• Complete Qn 7 and 8 (a,b &c) of Checkpoint
Pg 118.
• Write your answers on foolscap paper and
submit at the end of the next lesson.