A blanket to keep out the cold The Earth’s climate is driven by a continuous flow of energy from the sun. Heat energy from the sun passes through the Earth’s atmosphere and warms the Earth’s surface. As the temperature increases, the Earth sends heat energy (infrared radiation) back into the atmosphere. Some of this heat is absorbed by gases in the atmosphere, such as carbon dioxide (CO 2 ) , water vapour, methane, nitrous oxide, ozone and helacarbons. The greenhouse effect These gases, which are all naturally occurring, act as a blanket, trapping in the heat and preventing it from being reflected too far from the Earth. They keep the Earth's average temperature at about 15°C: warm enough to sustain life for humans, plants and animals. Without these gases, the average temperature would be about minus 18°C - too cold for higher life. This natural warming effect is also sometimes called the greenhouse effect. Carbon dioxide (CO 2 ) CO 2 is the most significant of the ...
Comments