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deforestation (increases the carbon dioxide level in atmosphere). Much of the recent observed
               and projected global warming is human induced.
               The atmospheric concentrations of carbon dioxide and methane have increased by 31% and
               149% respectively above pre-industrial level since 1750.
               Different effects of global warming are described below



                    During the past century, the atmospheric temperature has risen by 1.10° F (0.60° C).
                    Melting of polar ice resulting in increase in sea level (during the past century, sea level
                     has risen by several inches) and the risk of coastal flooding has increased.
                    Disruption of drinking water supplies dependent of snow melts.
                    Extinction of species.
                    More frequent tropical storms.
                    Increased incidence of tropical diseases.

               Action Taken
               A United Nations Conference on Climate Change, held in Tokyo, Japan, in 1997, resulted in
               an international agreement to fight global warming which called for reductions in emissions
               of greenhouse gases by industrialised nations.



               2. Ozone Depletion
               It refers to the phenomenon of reductions in the amount of ozone layer in the stratosphere.
               Causes/Effects
               It is caused by high levels of chlorine and bromine compounds in the stratosphere. Origin of
               these compounds are Chloroflurocarbons (CFCs), used as cooling substances in air
               conditioners and refrigerators or as aerosol propellants and bromofluro-carbons.(halons) used
               in fire extinguishers.
               Different effects of ozone depletion are described below


                    More ultraviolet radiation comes to Earth causing damage to living organisms, skin
                     cancer in humans, low production of phytopjankton affecting acquatic organisms.
                    Influences the growth of terrestrial plants.


                     Action Taken
                     Between 1979 to 1990, a reduction of 5% in ozone layer was detected. Since ozone
                     layer prevents most harmful ultraviolet radiation from passing through the Earth’s
                     atmosphere, so reduction in ozone layer generated worldwide concern, leading to
                     adoption of the montreal protocol banning the use of Chloroflurocarbon JCFC)
                     compounds as well as other ozone depleting chemicals such as carbon tetrachloride,
                     tricholoroethane (also known as methyl chloroform) and bromine compounds known as
                     halons.





               How to Save Environment?
               Following measures need to be taken to protect environment


                   Social awareness
                   Population control
                   Enforcement of Environment Conservation Act
                   Afforestation campaign
                   Control over industrial and agricultural pollution
                   Water management
                   Management of solid waste
                   Improvement in housing
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