To understand Global Warming, we should learn a bit more about Greenhouse gasses. The Earth receives solar radiation in the form of short waves. 30% of the radiation is immediately reflected back into the space by clouds and Ice, and the rest 70% is absorbed by the surface of the Earth. The Earth becomes warm in this process, and starts radiating heat into the atmosphere. Here is when the Greenhouse gasses intervene. Greenhouse gasses such as water vapor, carbon dioxide, methane and nitrous oxide absorb some of the radiation and stop it from escaping into the space. In this process Earth is prevented from cooling rapidly to sub zero temperatures.
Can Greenhouse gasses be produced by man made activities? What is the impact of such emissions? These questions would be answered in the subsequent sections. |
