3. Definition
Global warming is defined as an increase in the average
temperature of the Earth's atmosphere, especially a
sustained increase great enough to cause changes in the
global climate’.
Green House effect
The global warming potential (GWP) of a gas is defined
as the "radiative forcing" ( the additional radiative
power that the gas is sending back to the ground) of a
given quantity of gas, cumulated over a given period,
generally 100 years.
This value is actually never given as an absolute figure, but
relatively to CO2. The GWP of a gas is therefore "how much
more" (or how much less) it "enhances the greenhouse effect
over 100 years" (that is how much additional energy it sends
back to the ground) compared to a similar quantity of
CO2 emitted at the same time. 3
6. Important Green house gases
How it’s produced Avg. Life Time
CO2 Burning of fossil fuels, solid waste, and trees and wood
products. Changes in land use also play a role.
Deforestation and soil degradation add carbon dioxide to
the atmosphere, while forest regrowth takes it out of the
atmosphere
100 years
CH4 Production and transport of coal, natural gas, and oil.
livestock and agricultural practices and from the
anaerobic decay of organic waste in municipal solid waste
landfills.
12 Years
N2o Emitted during agricultural and industrial activities, as
well as during combustion of fossil fuels and solid waste.
114 years
CFCs A group of gases that includes hydrofluorocarbons,
perfluorocarbons, and sulfur hexafluoride, among other
chemicals. These gases are emitted from a variety of
industrial processes and commercial and household uses,
and do not occur naturally. Sometimes used as substitutes
for ozone-depleting substances such as
chlorofluorocarbons (CFCs).
A few weeks to
thousands of
years
6
8. How Global Warming Works
Fossil fuels (coal, oil, natural gas)
Carbon Dioxide (CO2)
8
9. Global warming
climatic events of the past 150
years have revealed that the
temperatures have risen all over the
globe, with the warming occurring in
two phases. The first phase was
from 1919 to 1940, with an average
temperature gain of 0.35°C, and
the second phase was from 1970 to
the present, exhibiting temperature
gains of 0.55°C.
Records show that the past 25
years have been the warmest time
of the past 5 centuries.
Red colour: Severe Global warming
Blue colour: < Normal temperatures9
10. How is global warming measured?
10
An Ice core is a core sample that is typically removed from
an ice sheet, most commonly from the polar ice caps of
Antarctica, Green land or from high mountain glaciers else
where.
when entrapped carbon dioxide levels are high, the
temperature goes up too.
Scientists use the ratio of heavy to normal water in ice layers
to estimate average temperatures at the time the ice was
made
17. Burning of Fossil Fuels
Pollution from coal,
natural gas, and oil
Pollution from coal,
natural gas, and oil
Pollution from coal,
natural gas, and oil 17
20. THE TOP FLOODS IN INDIA’S HISTORY
Year Name Death People affected
1987 Bihar 1400 people
5000 animal dead
29 millon people
2005 Maharashtra 5000 people
2005 Gujarat < 123 (11 days) 2,50,000
2007 South Asian 2000 (> 15 days) 30 million
2009 K, Ke, Ori, G,
NE
200 Million homes
2010 Ladakh 255 133 crores
2011 Indian Ker, WB, Bihar,
Assam
> 10 million people
2012 Northern Indian
Assam 27 9 lakh people
Ut. K, H P and Jammu,
resulting in landslides,
cloud bursts and flash
floods.
34 Hundreds
20
21. People evacuated from their homes due to the incessant
floods in India wade in the waters, searching for a place to
make camp during 2009
21
22. Drought
Of the total agricultural land in India, about 68% is prone to drought of
which 33% is chronically drought prone, receiving rainfall of less than
750mm per year. This is particularly the states of Maharashtra, Gujarat,
Rajasthan, Karnataka, Andhra Pradesh and Orissa. The World Record Of
Drought Was In 2000 in Rajasthan, India. 22
23. Portage Glacier
1914 2004
• Alaska
Photos: NOAA Photo Collection and Gary Braasch – WorldViewOfGlobalWarming.org
23
25. Arctic sea ice melting away
This photograph shows the extent
of sea ice in the summer of 1983.
Photo: NASA/Goddard Space Flight Center Scientific Visualisation Studio
Satellite photos show that by 2007 the
extent of summer sea ice was greatly
reduced
25
30. What’s being done now to
reduce our emissions?
Solar PowerWind Power Fuel-Efficiency
30
31. Simple Things To Do
Turn off your computer or the TV
when you’re not using it.
Take shorter showers. Heating water uses energy.
Keep rooms cool by closing the blinds, shades, or
curtains.
Turn off the lights when you leave a room.
Use compact fluorescent bulbs.
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32. Simple Things To Do
Dress lightly when it’s hot. Instead of turning up
the air conditioning, use a fan.
Dress warmly when it’s cold instead of turning
up the heat.
Offer to help your parents keep the air filters on
your AC and furnace clean.
Walk short distances instead of asking for a
ride in the car.
Plant a tree. Recycle.
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