How the Greenhouse Effect works

It's thought that the build-up of greenhouse gases impacts on global temperature in two ways:

  1. The gases allow more of the sun's rays to enter the atmosphere. Some solar radiation is still reflected back into space by the outer parts of the atmosphere, but it's believed the amount reflected back is gradually reducing.
  2. At the same time, the greenhouse gases absorb more of the solar radiation that is reflected back from the Earth's surface - trapping heat and keeping it in the atmosphere. The ability of the atmosphere to capture the Sun's warmth is essential for life on earth. But if significantly more warmth is being captured, this is bad news for the planet.
Diagram of the greenhouse effectThe greenhouse effect

The greenhouse effect therefore helps to keep the earth a little warmer than normal and this can lead the climate to change as global warming causes the atmosphere to warm up.

Many scientists believe that the carbon that is part of fossil fuels (coal, oil and natural gas), is one of main causes for the increase in carbon dioxide.

This then makes a much bigger contribution to the increase in greenhouse effect than any of the other gases.