The warming effect of the Earth's atmosphere. 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 car with its windows rolled up. A number of scientists believe that the emission of CO2 and other gases into the atmosphere may increase the greenhouse effect and contribute to global warming. (Climate Change: seeClimateChange.ca.gov gloss)