Greenhouse effect

     The greenhouse effect, is a warming of the Earth's surface and lower atmosphere that tends to intensify with an increase in atmosphere carbondioxide. The atmosphere allows a large percentage of the rays of visible light from the sun to reach the Earth's surface in the form of long-wave infrared radiation, much of which is absorbed by molecules of carbon dioxide and water vapour in the atmosphere and which is reflected back to the surface of the earth as heat. This trapped infrared radiation causes the Earth's surface and lower atmosphere layer to warm to a higher temperature.

        With this greenhouse heating, the Earth's average temperature would be only about -73°C(-100°F), even the ocean would be frozen under such conditions, so some amount of greenhouse effect (called natural greenhouse effect) is required to keep the Earth warm. Excessive heating can cause more damage to the environment.

      Due to the rise in atmospheric carbon dioxide  caused by the combustion of fossil fuels (coal, oil and natural gas), the greenhouse effect on Earth may be intensified and long term climate changes may result.

      An increase in concentrations of other gases such as chlorofluro carbons(Freons), nitrous oxide and methane, due to human activity may further increase the green house effect.