Global warming
Recently we heard of melting of ice and glaciers in the polar regions of Antarctica in the news paper. An important cause of global warming is the increase concentration of carbon dioxide level in the atmosphere. Since carbon dioxide is confined exclusively to the troposphere, its higher concentration may act as a serious pollutant. When there is increase in carbon dioxide concentration in the atmosphere, the thick layer of this gas prevents the heat from being re-radiated out. This thick carbon dioxide layer thus functions like the glass panel of a green house, allowing the sunlight to filter through but preventing the heat from being re-radiated in outer space. This is called green house effect.
Carbon dioxide layer and the water vapors present in the atmosphere absorbed most of the heat and add to the heat that is already present. The net result is the heating up of the earth’s atmosphere. Thus increasing carbon dioxide levels tend to warm the air in the lower layers of atmosphere on a global scale. Due to green house effect, there may be hurricanes and cyclones and early snow melts in mountains causing more floods during monsoon. Other toxic gases which are discharged from industry and agriculture also help in global warming. If the problem of global warming is unchecked it will cause a serious environmental problem.