Global warming – where we are

Abstract

Over last 8000 years, Earth’s surface temperature raised by 1◦ C only. But at the present rate of global warming, the temperature would rise by 2.5◦C by 2050. By the end of this century temperature would rise by another 2.5 ◦C. The Earth which was like an icebox has started burning. The sun sends energy as heat & light. Some part of the rays get through the atmosphere, some of them get reflected back into space. The ones which get through the atmosphere warm the earth up. All the time the earth radiates heat into space. Some of the heat going out is trapped by the atmosphere. This keeps our planet warm enough to live on. But if too much heat is trapped, the planet will warm up and the climate will change. The atmospheric air around the surface of the earth is made from a mixture of gases. Some of the gases trap heat, called greenhouse gases. This phenomenon is called natural greenhouse effect. Amount of greenhouse gases in the atmosphere is increasing day by day through human activities. More heat is trapped, enhanced greenhouse effect results. This is causing the earth to heat up universally called as – ‘Global warming’. It doesn’t just mean that the earth gets hotter; the whole climate is changing. Nitrogen & Oxygen make up 99% of the atmosphere, don’t trap heat, called non-greenhouse gases. Carbon dioxide, Methane, Nitrous oxide, Ozone, Water vapour – these gases make up 1% of the atmosphere, trap heat, called greenhouse gases. Human activities increases the amount of these gases in the atmosphere