The warming effect of the earth’s atmosphere on the earth. Light energy from the sun, which passes through the earth’s atmosphere, is absorbed by the earth’s surface and re-radiated into the atmosphere as heat energy. The heat energy is then trapped by the atmosphere, creating a situation similar to that which occurs in a greenhouse or a car with its windows rolled up. Many scientists believe that the emission of CO₂ and other gases into the atmosphere may increase the greenhouse effect and contribute to global warming.