The Low Carbon Partnership
Solar Power
The greenhouse effect
The sun provides the Earth with warmth. Its solar rays pass through the Earth’s atmosphere and reach the Earth’s surface. About 70% of the solar rays are absorbed by the Earth’s surface making the temperature rise; the rest of the heat is radiated back into the atmosphere in the form of infrared rays. Some of these infrared rays escape back out into space while some are absorbed by gases in the atmosphere.
These atmospheric gases are very important; first of all they allow the sun’s heat to pass through to the Earth, and then they trap some of that heat, like a blanket, to help maintain the planet at a stable temperature. As this process is a bit like the way a greenhouse works, it is called the greenhouse effect. The main gases that act in this way are carbon dioxide (CO2), water vapour, nitrous oxide and methane, and so they are known as ‘greenhouse gases’. The Earth is comfortable enough for humans, plants and animals to live on because this greenhouse effect maintains the temperature of the Earth as we now know it. Without this natural process the temperature on Earth would be intolerably cold.
