What causes the greenhouse effect?
The greenhouse effect is caused by gases in the atmosphere which have the ability to absorb the sun’s energy that is usually radiated back into space from Earth. Energy from the sun comes into the earth as short-wave radiation; some is absorbed and some is radiated back as long-wave radiation. The ‘greenhouse gases’ allow the short-wave radiation to pass through to Earth but absorb the long-wave radiation that is reflected back to space. These gases include naturally occurring gases – primarily water vapour, carbon dioxide, methane, nitrous oxides – as well as industrial chemicals such as chlorofluorocarbons (CFCs). The problem is that human activities have increased the atmospheric concentration of these gases well beyond their natural levels, and have introduced new greenhouse gases, such as CFCs. This in turn is throwing the natural climatic systems off balance. One of the major greenhouse gases from human sources is carbon dioxide (CO2). While CO2 is naturally occurring, its concen
