"The Greenhouse Effect,"" is it really as serious as everyone is making it out to be or is it just something that everyone is making a fuss over for no reason?.
The warming of the atmosphere that is due to the absorption and reradiation of heat by the molecules of certain gases, commonly known as greenhouse gases. Solar radiation is emitted at all wavelengths. Very short-wave, high energy gamma and X radiation is absorbed at the top of the atmosphere and does not penetrate it. The shorter wavelengths of ultraviolet radiation are absorbed by atmospheric oxygen.
The radiation that penetrates deeply into the atmosphere is predominantly at wavelengths between 0.2 Ãm and 4.0 Ãm, with a strong peak at 0.5 Ãm. Visible light is radiation at wavelengths between 0.4 Ãm (violet) and 0.7 Ãm (red); the 0.5m peak corresponds to blue-green light. Radiation between 0.7 Ãm and 4.0 Ãm corresponds to infrared radiation and heat. Out of all the radiation Earth receives from the Sun, 9 percent is ultraviolet, 45 percent is visible light, and 46 percent infrared and heat.
Some of the incoming energy is reflected into space from clouds and from the different surfaces of the land and sea. The remainder is absorbed. The absorbed radiation warms the surface, and as it warms the Earth starts to radiate as a blackbody. This radiation is at much longer wavelengths, between about 5 Ãm and 50 Ãm, with a strong peak at about 12 Ãm.
The gases the atmosphere comprises are transparent to incoming solar radiation, but the atmosphere is partly opaque to outgoing long-wave radiation. Certain molecules absorb radiation at wavelengths determined by their own size and shape. Water vapor absorbs radiation at 5.3-7.7 Ãm and at wavelengths higher than 20 Ãm, for example; carbon dioxide absorbs at 13.1-16.9 Ãm; and ozone absorbs at 9.4-9.8 Ãm. No gas absorbs radiation at 8.5-13.0 Ãm. This is the atmospheric window through which radiation escapes into space.