Greenhouse gases are crucial to keeping our planet at a suitable temperature for life. Without the natural greenhouse effect, the heat emitted by the Earth would simply pass outwards from the Earth’s surface into space and the Earth would have an average temperature of about -20°C.

 

A greenhouse gas is called that because it absorbs infrared radiation from the Sun in the form of heat, which is circulated in the atmosphere and eventually lost to space. Greenhouse gases also increase the rate at which the atmosphere can absorb short-wave radiation from the Sun, but this has a much weaker effect on global temperatures.

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The carbon dioxide released from the burning of fossil fuels is accumulating as an insulating blanket around the Earth, trapping more of the Sun’s heat in our atmosphere. Actions carried out by humans are called anthropogenic actions; the anthropogenic release of carbon dioxide contributes to the current enhanced greenhouse effect