Global Warming Its Causes and effects.

1. Global Warming
Submitted by:
Muhammad khuzaima
(14041561-011)

2. Global Warming
 A gradual increase in the overall temperature of the
earth's atmosphere generally attributed to the
greenhouse effect caused by increased levels of
carbon dioxide, CFCs, and other pollutants.

3. Global warming

4. How global warming work?
 Earth transforms sunlight's visible light energy into
infrared light energy, which leaves Earth slowly
because it is absorbed by greenhouse gases. When
people produce greenhouse gases, energy leaves
Earth even more slowly – raising Earth's
temperature.

5. How Global Warming Works
Fossil fuels (coal, oil, natural gas)
Carbon Dioxide (CO2)

6. Causes of Global warming
 Greenhouse gases
 Aerosols and soot
 Solar activity
 Variations in Earth's orbit
 Climate models

7. Greenhouse
 The trapping of the sun's warmth in a planet's lower
atmosphere, due to the greater transparency of the
atmosphere to visible radiation from the sun than to
infrared radiation emitted from the planet's surface.

8. Greenhouse Effect

9. How does the greenhouse effect work?
 Gases in the atmosphere such as carbon dioxide do
what the roof of a greenhouse does. During the
day, the Sun shines through the atmosphere. Earth's
surface warms up in the sunlight. At night, Earth's
surface cools, releasing the heat back into the air

13. What are the Greenhouse Gases?
 Many chemical compounds found in the Earth’s
atmosphere act as “greenhouse gases.” These gases
allow sunlight to enter the atmosphere freely. When
sunlight strikes the Earth’s surface, some of it is
reflected back towards space as infrared radiation
(heat). Greenhouse gases absorb this infrared
radiation and trap the heat in the atmosphere.
 There are many gases which exist that either directly
or indirectly act as greenhouse gases. Furthermore,
some gases have more dramatic effects then others.

14. Direct Greenhouse Gases
Carbon Dioxide (CO2)
 Carbon dioxide is without doubt the most well
known greenhouse gas. It is also the greenhouse gas
man contributes to most, primarily through burning
fossil fuels. Since the industrial revolution
concentrations of carbon dioxide in our atmosphere
have increased at an even faster rate.
 So how quickly are CO2 levels rising?

15. Main Sources of CO2
 1) Stationary energy consumption (eg. power stations)
 - coal fuelled power generation is the worst culprit for carbon dioxide
emissions
- Oil and gas fuelled energy generation tends to have a lower carbon
dioxide emission but due to its high use, still accounts for about half
of all human caused C02 emissions.
- Even those energy generation strategies without apparent use of fossil
fuels generally have some associated carbon dioxide emissions.
Nuclear power, for instance, relies on large amounts of electricity for
fuel processing and so indirectly results in carbon dioxide emissions.

16. Main Sources of Co2
 2) Transportation
- Globally, transport related emissions of carbon dioxide are growing
rapidly. The use of petroleum as a fossil fuel for transportation
dominates carbon dioxide emissions from this source.
- Despite the rising costs of fuel, fuel consumption levels continue to
rise. The large consumption of gas through vehicles is impacted by
many factors including the following; number of vehicles on the
road, types of vehicles on the road (SUV’s, smart cars, transport
trucks, etc), traffic conditions, urban sprawl (distance vehicles have
to travel), and maintenance of vehicles (emissions tests, oil
changes).
- Energy use (stationary and transportation) are the main contributors
to human made CO2.

17. Direct Greenhouse Gases
Methane (CH4)
 Sources: Natural - Wetlands,
Termites, the Oceans
 Human Made - Ruminants
(livestock), Waste Treatment,
Rice Agriculture, Biomass
Burning

18. Direct Greenhouse Gases
Nitrous Oxide (N2O)
 Sources: Natural – The Oceans,
the Atmosphere, Soils
Human Made – Agricultural
soils, Biomass burning, Livestock,
Transportation

19. Other Direct Greenhouse Gases
 Tropospheric Ozone
 Water Vapor (in the stratosphere)
 CFC’s Chlorofluorocarbons
 HFC’s Hydrofluorocarbons
 Perfluorocarbons (PFCs) and sulphur hexafluoride
(SF6) with atmospheric lifetimes of more than 1000
years.

20. Indirect Greenhouse Gases
 Nitrogen oxides (NOx) act as indirect greenhouse gases by producing the
tropospheric greenhouse gas 'ozone' during their breakdown in the
atmosphere.
 Carbon monoxide (CO) - can lead to the formation of the tropospheric
greenhouse gas 'ozone'.
 Hydrogen (H2) - hydrogen increases the lifetime of some direct greenhouse
gases, such as methane.
 Volatile organic compounds or VOCs - encompasses many compounds
including hydrocarbons, alcohols, and organic acids. Man-made emissions tend
to be concentrated in highly populated areas such as cities

21. What Might Happen?
Cause and Effects
1) Global temperatures will rise!!!
 Is the climate warming? YES!
 Global surface temperatures have increased about 0.6°C since the late-
19th century, and about 0.2 to 0.3°C over the past 25 years
 How about each year, how hot is it really getting? Lets take a look at
the average temperatures since the 1880’s and see the projections of
where we are going.
 Then we can look at the top 20 hottest ever recorded yearly
temperatures!

22. The 20 Hottest Years on Record

23. 3) Drought
 An increase in the occurrence of drought – Areas that lack
precipitation over a long period of time.
 As fast as global warming is transforming the oceans and the ice
caps, it's having an even more immediate effect on land.

26. 4) Extreme Weather
 As the world warms, some extreme climate events, like the frequency of
heat waves and very heavy precipitation, are expected to increase.
 Blizzards and snow storms may actually increase in intensity and
frequency in some colder locations
 As climate change gathers pace, devastation caused by extreme weather
is becoming more common.

27. Bushfires are becoming more and more common due to intense heat and long
periods without precipitation. Bushfire numbers are especially on the rises in
countries like the US and Australia

28. Tornadoes are increasing in number and in severity, perhaps an effect of
global warming

29. Hurricanes are increasing in numbers and in severity, Hurricanes require
warm ocean temperatures in order to form.

30. Effects of Global Warming
Increased Temperature
Habitat Damage and
Species Affected Changes in Water Supply
Rising Sea Level

31. What’s the proof that global warming is
taking place?
 Portage Glacier
 Alaska
1914 2004

32. Colorado River
 Arizona
June 2002 Dec 2003

33. So how can each of us slow global
warming now?
 Replace a regular incandescent light bulb
with a compact fluorescent light bulb
 Don’t let heat escape from your house over a
long period
 Cover your pots while cooking
 Use the washing machine or dishwasher only
when they are full

34. So how can each of us slow global
warming now?
 Take a shower instead of a bath
 Use less hot water
 Recycle your organic waste
 Reuse your shopping bag
 Plant a tree
 Switch to green power