Global warming / Green house Gas effect

Green house Gas effect

Green house is a glass house that helps in artificial cultivation of plants by providing a conducive environment for their growth. GHE was given its name by French physicist named Joseph Fourier in 1827 who compared the Earth atmosphere to a closed glass vessel and observed that air around the earth filters sunlight exactly like glass roof.

Global warming refers to phenomena of increased trapping of terrestrial radiations (infra-red waves) because of increased concentration of GHG resulting in increase of average global temperature on the earth surface. GHG that are responsible for Green House effect in atmosphere include carbon –di-oxide

(Largest volume), methane, and chlorofluorocarbons (highest trapping capacity, oxide of nitrogen, sculpture hexafluoride and water vapors. GHG found in atmosphere cover the earth like a blanket. Although high concentrations of these gases are harmful to the environment, if these gases would not have been there then the temperature of the Earth would have been 18 ⁰C or- 19⁰ C. Of all GHG emitted in the atmosphere CO₂ and CH₄ are having maximum concentration, they both together account for 90% of the GHG emissions.

Because of excessive deforestation, use of fossil fuel, automobile exhaust and various other industrial activities. The level of CO₂ especially has significantly increased which has resulted in increased temperature of earth surface, in 1957 it was recorded 311 ppm (parts per million) and in 2005 it was recorded as 379 ppm. Global warming has occurred in two phases from 1910 to 1940 by about 0.350⁰C and more strongly from 1970 onwards to the present by about 0.55⁰ C, taking the global temperature to about 14.4⁰C. If the increased concentration of CO2 and other GHG continues this way by the end of 21^st century, earth will became altogether an inhabitable planted.

Impact of Global Warming

There will be changes in climatic conditions at local, regional and global levels with environmental, social economic and political effects. The main ecological effects will be as follows:

1.       Changes the composition of atmospheric gases due to increased level of CO₂ and resulting global heat imbalance.

2.       Rise in the temperature or earth’s surface, oceans and lower atmosphere.

3.       Hydrological cycle would be disturbed. Decrease in precipitation and soil moisture content in the most agricultural regions of the world would be observed.

4.       Melting of the continental and polar glaciers, ice caps etc. resulting in rise in sea level. This in turn would submerge many islands and coastal ecosystems.

5.       Acidity of the ocean may increase due to dissolution of more amount of CO₂ in water. This along with rise of oceanic temperature would eliminate many oceanic plant and animal species, and endanger the whole oceanic ecology.

6.       Global warming itself would increase ozone depletion.

7.       Increase in the frequency and intensity of Extreme Weather Events such as tropical cyclones, hurricanes, droughts, floods, etc, as seen in last decade and particularly in 2012.

8.       Plant and animal biomass production would vary in different regions of the world.

9.       The socio-economic costs of global warming such as displacement of people in coastal areas, decreased agricultural productivity due to erratic weather effects on urban economy etc. will be seen. The developing countries will bear the higher brunt of it due to large and dense population, limited mitigation and adaptation technologies and scarce finance.