In last few hundred years the global environment is changing due to the various activities of human beings . To cater to the needs of the huge population and due to the advancement in science and technology , human beings are trying to manipulate the environment. In doing so they have caused environmental imbalance and a number of environmental problems like
- conversion of forests to grazing lands or croplands by the deforestation has caused loss of carbon stored in soil and vegetation to the atmosphere ultimately affecting global carbon level
) the excessive emission of green house gases- carbon dioxide , methane, nitrous oxide and cfc.
The excessive increase in the concentration of green house hases in the atmosphere would retain more and more of the infrared radiationsresulting in the enhanced green house effect.
As a result of the enhanced green house effect, the consequent increase in the global mean temperature is called global warming. The intergovernmental panel on climate change ( IPCC) periodically makes an assessment of the abundance of the green house gases in the atmosphere and their possible impact on the climate and related issues .
Carbon dioxide is the most abundant green house gas in the atmosphere. It's level has increased by 31% due to industralisation since 1750. Methane concentration has more than doubled since 1750 as a result of industrialization.
The increased green house warming caused mainly by carbon dioxide is spiralling out of control as a result of human activities. With the industrialization every year industrial activities release almost 6000 million tones of co2 into the atmosphere along other green house gases such as methane .
Detailed studies have shown that the average global temperature of the earth's surface has increased by 0.5 degree Celsius in last 100 years. If their emission continue in the current rate , the earth could heat up to 0.3 degree Celsius each decade.