ld be
             colder by about 33 degrees Celsius, and ice would cover earth from pole to pole."
             In the late 1800's Swedish scientist Svante Arrenius proved that gases like carbon
             dioxide could trap heat. Natural levels of carbon dioxide in the atmosphere absorb heat
             from the sun and keep our planet habitable. However, it is the recent unnatural increase in
             carbon dioxide and other greenhouse gases caused by human activity that is a cause for
             great concern. The industrial revolution has poisoned our world by promoting total
             disregard for the planet that we live in so millions of people can have more money to
             The greenhouse effect is called so because it is like a greenhouse that you keep
             plants in. The sun's rays come into the greenhouse and a lot of the warmth from the
             energy is trapped inside by the glass. The greenhouse effect that causes global warming
             occurs when the greenhouse gases act like the glass. When sunlight travels through the
             atmosphere coming from the sun it travels as short wavelength energy. The earth's
             atmosphere is transparent to short wavelength energy and all of it entering the
             atmosphere makes it to the surface of the earth. On the contrary when visible light
             reflects off the earth's surface, the energy is converted to long wave length infrared
             radiation. Partially opaque greenhouse gases and water vapour in the lower atmosphere
             absorb the radiation heat. (see fig. 1) (Gay, Kathlyn, The Greenhouse Effect, 1996)
             The main gases that contribute to the human caused greenhouse effect are carbon
             dioxide, nitrous oxide, methane, chlorofluorocarbons (CFC's), hydroflorocarbons
             (HFC's), perflorocarbons (PFC's), and sulfur hexafloride (SF6). Each greenhouse gas
             absorbs a different amount of heat in our atmosphere. Methane traps over 21 times more
             heat than carbon dioxide and nitrous oxide traps 270 times more heat than carbon
             ...