PPT On global warming

2. All across the world, in every kind of environment and region known to man, increasingly
dangerous weather patterns and devastating storms are abruptly putting an end to the
long-running debate over whether or not climate change is real. Not only is it real, it's here,
and its effects are giving rise to a frighteningly new global phenomenon: the man-made
natural disaster.

3. CONTENTS
What is Global Warming
Greenhouse Effect
Causes of global warming
Rise in sea level
Ozone layer depletion
Forest cover depletion
Effects on ecological system(Humans,
Marine Lives)
Islands/peninsular danger of being
submerged
Conclusion
Thank You

4. Global warming is the rising average temperature
of Earth’s atmosphere and oceans since the late
.
19th century and its projected continuation. Since
the early 20th century, Earth's average surface
temperature has increased by about 0.8 °C
(1.4 °F), with about two thirds of the increase
occurring since 1980. Warming of the climate
system is unequivocal, and scientists are more than
90% certain that most of it is caused by
increasing concentrations of greenhouse gases
produced by human activities such as deforestation
and the burning of fossil fuels. These findings are
recognized by the national science academies of all

5. The greenhouse effect is a process by which thermal
radiation from a planetary surface is absorbed by atmospheric
greenhouse gases, and is re-radiated in all directions. Since
part of this re-radiation is back towards the surface and the
lower atmosphere, it results in an elevation of the average
surface temperature above what it would be in the absence of
the gases.
Earth’s natural greenhouse effect makes life as we know it
possible. However, human activities, primarily the burning of
fossil fuels and clearing of forests, have intensified the natural
greenhouse effect, causing global warming.

7. POLLUTION
BURNING OF FOSSIL
FEULS DEFORESTATION
OVERPOPULATION RESOURCE
• EXESS VECHICLE USE MISEXPLOITATION

11. Scientists say that the
barrier insulating the
continental ice caps is
melting.
“The impacts of
warming temperatures in
Antarctica are likely to
occur first in the
northern sections of the
continent, where
summer temperatures
approach the melting
point of water, 32 degrees
F (0 degrees C).”

12. As the ice melts, big chunks of
glaciers will break off and
become like ice cubes in a big
glass of water. The ice chunks,
known as icebergs, create mass
in the ocean. The icebergs
displace the water causing the
ocean level to rise. Some of the
shoreline in many places like
Florida (where the land is at a
low altitude) will go under water.

13. At present, sea levels around the
world are rising. Current sea level
rise potentially impacts human
populations (e.g., those living in
coastal regions and on islands)and
the natural environment (e.g.,
marine ecosystems).Global average
sea level rose at an average rate of
around 1.7 ± 0.3 mm per year over
1950 to 2009 and at a satellite-
measured average rate of about 3.3
± 0.4 mm per year from 1993 to
2009, an increase on earlier
estimates. It is unclear whether the
increased rate reflects an increase
in the underlying long-term trend.

14. Ozone depletion describes two distinct but
related phenomena observed since the late 1970s: a
steady decline of about 4% per decade in the total
volume of ozone in Earth’s stratosphere (the ozone
layer), and a much larger springtime decrease in
stratospheric ozone over Earth's polar regions. The
latter phenomenon is referred to as the ozone
hole. In addition to these well-known
stratospheric phenomena, there are also
springtime polar tropospheric ozone depletion
events.

15. CFCs and other contributory substances are referred to as
ozone-depleting substances (ODS). Since the ozone
layer prevents most harmful UVB wavelengths (280–
315 nm) of ultraviolet light (UV light) from passing
through the Earth's atmosphere, observed and projected
decreases in ozone have generated worldwide concern
leading to adoption of the Montreal Protocol that bans
the production of CFCs, halons, and other ozone-
depleting chemicals such as carbon tetrachloride and
trichloroethane. It is suspected that a variety of
biological consequences such as increases in skin cancer,
cataracts,[3] damage to plants, and reduction of plankton
populations in the ocean's photic zone may result from
the increased UV exposure due to ozone depletion.

17. Deforestation is the removal of a forest or stand of trees where the
land is thereafter converted to a nonforest use. Examples of
deforestation include conversion of forestland to farms, ranches, or
urban use.
The term deforestation is often misused to describe any activity
where all trees in an area are removed. However in temperate
climates, the removal of all trees in conformance with sustainable
forestry practices—is correctly described as regeneration harvest. In
temperate mesic climates, natural regeneration of forest stands
often will not occur in the absence of disturbance, whether natural
or anthropogenic. Furthermore, biodiversity after regeneration
harvest often mimics that found after natural disturbance, including
biodiversity .

19. Global warming is caused by the emission of greenhouse gases . 72%
of the totally emitted greenhouse gases is carbon dioxide (CO2).
Therefore CO2 emissions are the most important cause of global
warming .
CO2 is created by burning fossil fuels like e.g. oil, natural gas, diesel.
The emissions of CO2 have been dramatically increased within the
last 50 years and are still increasing (CO2 emissions by country).
Carbon dioxide remains in the atmosphere for 80 to 200 years.
According to recent investigations, unimaginable catastrophic
changes in the environment are expected to take place if the global
temperatures increase by more than 2° C (3.6° F). A warming of 2° C
(3.6° F) corresponds to a carbon dioxide (CO2) concentration of
about 450 ppm (parts per million) in the atmosphere.
The current (year 2007) concentration of CO2 is at about 380 ppm
and it is currently increased by 2 to 3 ppm each year.

21. The world-wide emissions of CO2 for the year 2006 was
about 28 billion tonnes. What would happen if we froze
the world-wide emissions of carbon dioxide to the
current level? Could global warming be mitigated? For
this purpose, we simulate a constant emission of 30
billion tonnes of carbon dioxide per year.
The blue curve again shows the effect on the average
temperature increase. The increase is less steep than in
the example above, but the red zone with temperature
increases of more than 2 C is still reached. Devastating
effects on our environment can be expected to start
around the year 2075.

23.  “Penguin
population decline.
Adeliepenguin
populations have
shrunk by 33
percent during the
past 25 years in
response to
declines in their
winter sea ice
habitat.”

24. “Coral reef bleaching, the whitening of diverse
invertebrate taxa, results from the loss of
symbiotic zooxantheallae and/or a reduction in
photosynthetic pigment concentrations in
zooxanthellae residing within scleractinian corals.
Coral reef bleaching is caused by various
anthropogenic and natural variations in the reef
environment including sea temperature, solar
irradiance, sedimentation, xenobiotics, subaerial
exposure, inorganic nutrients, freshwater
dilution, and epizootics. Coral bleaching events
have been increasing in both frequency and
extent worldwide in the past 20 years. Global
climate change may play a role in the increase in
coral bleaching events, and could cause the
destruction of major reef tracts and the extinction
of many coral species.”

25. Global warming is not something whose effects will be
felt centuries later, it is already affecting our lives. The
recent scorching weather is not purely an act of nature.
Neither is the increasingly volatile weather that is
wreaking havoc in certain parts of the globe. Humans are
causing global warming and we are suffering as a result,
and the consequences will only get heavier.
The increased temperatures are not only melting
icebergs and glaciers, it is also causing animals to migrate
to different areas or die, upsetting ecosystems, and it is
also changing precipitation patterns.

26. Melting of polar ice caps and flooding
The effects of global warming are
strongest at the poles. Ice all over
the world is melting. This includes
the ice on mountain glaciers,
Arctic sea ice and ice sheets
covering West Antarctica and
Greenland. The melting ice
increases the sea level and this
causes flooding of low-lying areas.
When snow and ice melt, their
ability to reflect sunlight is lost,
escalating global warming even
further.

27. Irregular weather patterns have an effect on humans. Rain is not
only an inconvenience for humans, but storms damage human
property. The increase in heat will increase evaporation which is why
there will be more rain. Animals and plants cannot easily adapt to
increased rainfall or snowfall and many animals migrate to other
areas. Plants can die as a result and this can cause an ecosystem to
collapse as plants are the main source of food in an ecosystem.

28. Changes in Food Production
The world has had a food crisis and global
warming may have been to blame for it. At the
moment global warming does not have much
of an impact on this, but in the future, there
will be impacts.
As temperatures around the world will
increase, plants will find it harder to cope and
they will die. Some of these plants are used by
humans for food and so a food shortage may
occur. Plants create food for themselves
through a process called photosynthesis. The
enzymes that are needed for photosynthesis die
when exposed to high temperatures. Pests may
also migrate to new areas and destroy the crops
there. Pests may migrate from tropical
countries to temperate countries.

29. Human Health
Rising temperatures have an effect on the
health of humans and the diseases that
they are exposed to.
Human health will be affected. The world
glimpsed this in 2003 when Europe was
struck by heat waves and people died.
Heat strokes are likely to increase as
temperatures get hotter.
Diseases such as malaria are likely to
spread. Parasites that originate in tropical
regions may migrate to temperate regions
as they become warmer. Mosquitoes are
an example and it is predicted that
malaria will spread around the world. It is
also predicted that asthma will increase
around the world as allergens that cause
asthma will become more common.

31. Rising seas, caused by global warming, have for the first
time washed an inhabited island off the face of the
Earth. The obliteration of Lohachara island, in India's
part of the Sundarbans where the Ganges and the
Brahmaputra rivers empty into the Bay of Bengal,
marks the moment when one of the most apocalyptic
predictions of environmentalists and climate scientists
has started coming true.
As the seas continue to swell, they will swallow whole
island nations, from the Maldives to the Marshall
Islands, inundate vast areas of countries from
Bangladesh to Egypt, and submerge parts of scores of
coastal cities.

32. Eight years ago, as exclusively reported in The Independent on
Sunday, the first uninhabited islands - in the Pacific atoll nation
of Kiribati - vanished beneath the waves. The people of low-lying
islands in Vanuatu, also in the Pacific, have been evacuated as a
precaution, but the land still juts above the sea. The
disappearance of Lohachara, once home to 10,000 people, is
unprecedented.
It has been officially recorded in a six-year study of the
Sunderbans by researchers at Calcutta's Jadavpur University. So
remote is the island that the researchers first learned of its
submergence, and that of an uninhabited neighboring island,
Suparibhanga, when they saw they had vanished from satellite
pictures.

33. Two-thirds of nearby populated island Ghoramara has also been
permanently inundated. Dr Sugata Hazra, director of the
university's School of Oceanographic Studies, says "it is only a
matter of some years" before it is swallowed up too. Dr Hazra says
there are now a dozen "vanishing islands" in India's part of the delta.
The area's 400 tigers are also in danger.
Until now the Carteret Islands off Papua New Guinea were expected
to be the first populated ones to disappear, in about eight years'
time, but Lohachara has beaten them to the dubious distinction
Human cost of global warming: Rising seas will soon
make 70,000 people homeless
Refugees from the vanished Lohachara island and the disappearing
Ghoramara island have fled to Sagar, but this island has already
lost 7,500 acres of land to the sea. In all, a dozen islands, home to
70,000 people, are in danger of being submerged by the rising seas.

35. Global warming is affecting
plants, animals, humans and
the earth. We need to learn
how to conserve our use of
fossil fuels to minimize carbon
dioxide production. This will
slow down the effects of global
warming. Before its too late……..