The Greenhouse Effect explained:
The Scientific Bit…
The Greenhouse effect is caused by a group of gases in the earth’s atmosphere. A few of these gases have seen increased levels over the past hundred years. The six main ones are carbon dioxide (CO2), methane (CH4) and nitrous oxide (N20) as well as what are called halocarbon gases- chlorofluorocarbons (CFCs), hydro-fluorocarbons (HFCs), perfluorocarbons (PFCs) and sulphur hexafluoride (SF6).
Greenhouse gases allow incoming radiation from the Sun to pass through the Earth’s atmosphere. The Earth then reflects this radiation back but on the way some is trapped by the greenhouse gases, causing them to warm up. The greenhouse effect is essential for sustaining life on Earth, as without it the temperature would be too low. The problem that scientists are so concerned about is that certain processes that have been used by humans on a large scale over the past century or so create extra greenhouse gases as by-products.
These added levels of greenhouse gases are causing the overall temperature of the Earth to gradually rise, which is causing the climate to change.