The world is a greenhouse. The role of the atmosphere is to insulate and heat the surface of the earth. The greenhouse effect is not a new phenomenon. Humans can help reduce the growing greenhouse effect. The atmosphere insulates and heats the surface of the earth. Incoming solar radiation passes through the atmosphere. The earth's surface absorbs some of the radiation. Unabsorbed radiation is emitted in the form of infrared radiation. Gases such as carbon dioxide, methane, nitrous oxide and water vapor absorb reflected infrared radiation. These gases emit infrared radiation, some of which is absorbed by the earth. The greenhouse effect is the absorption of infrared energy by the Earth's surface and atmosphere. The greenhouse effect is not a new phenomenon. As far as scientists know, the sun has always shone on earth. Furthermore, the earth has always had an atmosphere. The atmosphere and the gases it contains have been capturing and trapping solar radiation since the beginning of time. Life could not continue and would not have begun without the atmospheric gases that create the greenhouse effect. Humans can help reduce the greenhouse effect. By reducing the amount of gases released into the atmosphere, humans can reduce infrared radiation, which causes the greenhouse effect. There are several ways to control the amount of gases released. Humans could take advantage of existing bus, subway and train systems. Carpooling is another way humans could reduce the amount of harmful gases released into the atmosphere. Filling your gas tank and mowing the grass after dark are additional ways to reduce the greenhouse effect.