What is the Green house effect ?
The Earth is kept warm by it's atmosphere, which acts rather like a woolly coat - without it, the average surface temperature would be about -18 degrees Centigrade. Heat from the sun passes through the atmosphere, warming it up, and most of it warms the surface of the planet. As the Earth warms up, it emits heat in the form of infra-red radiation - much like a hot pan emits heat even after it's taken away from the cooker. Some of this heat is trapped by the atmosphere, but the rest escapes into space. The so-called "greenhouse gases" make the atmosphere trap more of this radiation, so it gradually warms up more than it should, like a greenhouse (although a greenhouse actually does this by stopping warm air rising and escaping from it).
Problems of The Greenhouse Effect
The greenhouse effect causes trouble by raising the temperature of the planet. The actual rise is not very much, but the Earth's ecosystem is very fragile, and small changes can have large effects.
| A Panel on Climate Change has predicted that this rise of one degree will happen by the year 2025. What Causes The Greenhouse Effect? Causes of the greenhouse effectThis could potentially cripple the North American corn belt, which produces much of the world's grain, leading to much higher food prices, and even less food for the Third World than they already have. However, it would also mean that some countries which are further north would be able to grow crops they had never been able to before, although there is less land as you move north from the corn belt. The other serious worry is that rising sea levels from the melting of the polar ice caps could severely flood many countries. A rise in sea levels of one metre, which many experts are predicting by the year 2100 (and some as soon as 2030), would flood 15 percent of Egypt, and 12 percent of Bangladesh. The Maldives in the Indian Ocean would almost completely disappear. |
Most of the countries which would suffer most from a rise in sea levels are the poor island states, so the islands in the Caribbean, South Pacific, Mediterranean and Indian Ocean have formed the Alliance of Small Island States, AOSIS, so they have a louder voice in international politics and can make the richer developed world listen to their problems. Britain would lose most of East Anglia, and to protect the coast line would cost an estimated 5 to 10 billion pounds.
The Greenhouse Effect - Possible Solutions
Reducing use of fossil fuels would considerably reduce the amount of carbon dioxide produced, as well as reducing the levels of the pollutants which cause acid rain. This can be achieved by either using less energy altogether, or using alternative energy sources. You can help save energy in lots of ways:
- Turn off lights when you leave a room
- If you have a car, don't use it for short journeys
- Basically, anything at all that uses less energy
Eliminating the use of CFCs is something we can actually do.
Chlorofluorocarbons (CFCs) were invented in the 1920s, they are a compound of carbon containing chlorine and fluorine. CFCs are man made chemicals, so we call them synthetic chemicals. Since their introduction CFCs have been used as:
- Refrigerants in refrigerators and air conditioning units
- Propellants in aerosol cans
- Foaming agents in the production of packaging
- Cleaners used in the electronics industry
- Fire extinguisher chemicals
New refrigerants have been developed, and new aerosols use other propellants such as butane, so it is now actually quite difficult to get hold of CFCs (assuming you wanted to get some for something anyway).
Stopping deforestation by using renewable forests and planting a new tree whenever one is felled would help to raise the carbon dioxide absorbing ability of the planet.
