The document discusses the history of the Earth's climate and global warming. It explains that global warming is caused by increased greenhouse gases trapping heat from the sun. Greenhouse gases like carbon dioxide are emitted through human activities such as burning fossil fuels and deforestation. The document also discusses the effects of global warming that are already occurring, such as rising sea levels, as well as future effects like impacts on agriculture and rising temperatures causing ice melting. Solutions proposed to address global warming include reducing fossil fuel consumption and switching to alternative energy sources.

1. SAVE OUR EARTH
Prem Deshmane

3. Earth formed ~4.6 billion years ago
Originally very hot
Sun’s energy output only 70% of
present
Liquid water present ~4.3 billion
years
History of Earth’s Climate

4.  Life appeared ~3.8 billion years ago
 Photosynthesis began 3.5-2.5 billion years ago
 Produced oxygen and removed carbon dioxide and
methane (greenhouse gases)
 Earth went through periods of cooling (“Snowball
Earth”) and warming
 Earth began cycles of glacial and interglacial periods
~3 million years ago
History of Earth’s Climate

5. Global Warming is the increase of Earth's average
surface temperature due to effect of greenhouse gases,
such as carbon dioxide emissions from burning fossil
fuels or from deforestation, which trap heat that would
otherwise escape from Earth. This is a type of
greenhouse effect.
Do you know what is GLOBAL
WARMING ?

6.  Greenhouse gas: Greenhouse gas emissions, such as
carbon dioxide (CO2), nitrous oxide and methane from
automobile exhausts and industries, trap heat in the
atmosphere.
 Deforestation: Extensive logging is removing trees and
plants that would otherwise absorb CO2.
Reasons for GLOBAL WARMING

7.  Oceans' absorption of CO2: Oceans help maintain a
delicate equilibrium by absorbing CO2 from the
atmosphere and reflecting heat from the sun. But this
balance is difficult to match with global CO2 emission
levels.
 Loss of sea ice: Glaciers help maintain the temperature
of oceans, but with ice melting, there is less heat that is
reflected back and more water to absorb it.

8.  The Earth's average surface temperature rose by
0.74=0.18 °C over the period 1906–2005. The rate of
warming over the last half of that period was almost
double that for the period as a whole (0.13±0.03 °C per
decade, versus 0.07±0.02 °C per decade). The urban heat
island effect is very small, estimated to account for less
than 0.002 °C of warming per decade since 1900
TEMPERATURE RISING !!

9.  The greenhouse effect is the process by which absorption and
emission of infrared radiation by gases in the atmosphere are
purported to warm a planet's lower atmosphere and surface.
 Naturally occurring greenhouse gases have a mean warming
effect of about 33 °C (59 °F).
 The major greenhouse gases are water vapor, which causes
about 36–70 percent of the greenhouse effect; carbon dioxide
(CO2), which causes 9–26 percent; methane (CH4), which
causes 4–9 percent; and ozone (O3), which causes 3–7
percent. Clouds also affect the radiation balance, but they are
composed of liquid water or ice and so have different effects
on radiation from water vapour.
GREEN HOUSE EFFECT

10. Annual world greenhouse gas
emissions, in 2012, by sector.

11. Natural causes are causes that are created by nature. One
natural cause is a release of methane gas from arctic tundra
and wetlands. Methane is a greenhouse gas and a very
dangerous gas to our environment. A greenhouse gas is a
gas that traps heat in the earth's atmosphere. Another
natural cause is that the earth goes through a cycle of
climate change. This climate change usually lasts about
40,000 years.
NATURAL CAUSES

12.  Man-made causes probably do the most damage to our
planet. There are many man-made causes of global
warming. Pollution is one of the biggest man-made
problems. Pollution comes in many shapes and sizes.
Burning fossil fuels is one thing that causes pollution.
Fossil fuels are fuels made of organic matter such as
coal, or oil. When fossil fuels are burned they give off a
green house gas called CO2. When you dig up the fossil
fuels you dig up the methane as well letting it escape
into the atmosphere.
MAN-MADE CAUSES

13.  The effects of Global Warming can already be seen
The IPCC's Third Assessment Report finds that in the last 40
years, the global average sea level has risen, ocean heat
content has increased, and snow cover and ice extent have
decreased, which threatens to inundate low-lying island
nations and coastal regions throughout the world.
 Effects of global warming already being felt on plants and
animals worldwide
 Global Warming Effects that will happen in the future:
EFFECTS OF GLOBAL WARMING

14.  Global warming will affect agriculture. New crops will
be able to be grown in areas that are currently too cold to
support them. However, more pests and diseases may
offset any benefits higher temperatures may have. Water
resources will also be affected.
 Global warming will have serious impacts on the
environment and on society. Higher temperatures will
cause a melting of ice in Greenland and Antarctica. This
will accelerate the rise of sea level. The speed at which
global warming is expected to occur in the 21st century
is faster than most plant and animal species will be able
Effects of Global Warming on Earth in
Future

15.  The ozone layer protects the Earth from the ultraviolet rays
sent down by the sun. If the ozone layer is depleted by
human action, the effects on the planet could be catastrophic.
 Ozone is a bluish gas that is formed by three atoms of
oxygen. The form of oxygen that humans breathe in consists
of two oxygen atoms, O2. When found on the surface of the
planet, ozone is considered a dangerous pollutant and is one
substance responsible for producing the greenhouse effect.
OZONE LAYER DEPLETION

16. Useless usage of AC's and Refrigerators should be stopped
because from them harmful rays cfc's are emitted which
results in depletion of ozone layer and from that hole UV
rays of Sun comes to the earth and cause many diseases to
both animals and plants i.e. Skin cancer etc. , CNG and
hydrogen operated vehicles should be used, more no. of
trees should be planted, Chimneys in the Industries should
be upgraded so that most of the effluents should get
filtered down there.
PRECAUTION TO PREVENT
GLOBAL WARMING

17. Because greenhouse gas emissions are tied very closely to
our energy consumption, using less fossil fuel based
energy puts fewer greenhouse gases into the atmosphere.
 This will help slow global warming.
Reduce our consumption of fossil fuels