Solved Paper-I On Topic :

Que : 1 . Which one of the following green house gases has the shortest residence time in the atmosphere ? (J-2014)

1. Chlorofluorocarbon
2. Carbon dioxide
3. Methane
4. Nitrous oxide
Please Select Ans Options .

Option 3 is Correct Answer
Methane is the second most important green house gas. A greenhouse gas (abbreviated GHG) is a gas in an atmosphere that absorbs and emits radiation within the thermal infrared range. This process is the fundamental cause of the greenhouse effect. The primary greenhouse gases in Earth's atmosphere are water vapor, carbon dioxide, methane, nitrous oxide, and ozone. Without greenhouse gases, the average temperature of Earth's surface would be about 15 ?C (27 ?F) colder than the present average of 14 ?C (57 ?F). In the Solar System, the atmospheres of Venus, Mars and Titan also contain gases that cause a greenhouse effect. contribution to the greenhouse effect as fallows. Compound Formula Contribution (%) Water vapor and clouds H2O 36-72% Carbon dioxide CO2 9-26% Methane CH4 4-9% Ozone O3 3-7%