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The protective layer of the Earth, the ozone layer, which protects the Earth from the sun’s destructive ultra-violet rays, is being damaged by CFCS (chlorofluorocarbons). They are released by the daily use of industrial and household products: refrigerators, air conditioners, foam insulation, cleaning chemicals, food packaging. In the ozone layer they attack the ozone molecules making a “hole”, which allows more UV rays to penetrate to the Earth. It contributes to global warming, increasing the risk of skin cancer, eye cataracts, weakens the immune system of people. Besides, UV rays influence the oceans, the growth of plankton, cause skin and eye problems in animals too, reduce economically important crops (rice, cotton, soy beans).
Acid Rain
One of the most alarming forms of air pollution is acid rain. It results from the release into the atmosphere of sulphur and nitrogen oxides that react with water droplets and return to earth in the form of acid rain, mist or snow. Acid rain has caused much damage in Europe and the US. Forests in Vermont are dying because of the pollution from the power station in Ohio. The trees in Europe are dying too –64 per cent of them in Britain and 50 per cent in West Germany, Chechoslovakia, Greece, Sweden, Belgium and Holland are also badly affected. The acid rain has dissolved metals and other pollutants and washed them into the water. It washes metals into drinking water to and this can cause serious illness. It has acidified lakes and streams and they cannot support fish, wildlife, plants or insects. Many buildings and even railway lines, are being destroyed by acid rain.
Deforestation
Thirty years ago, forests covered a quarter of the Earth’s land area. Today they cover only a fifth – a sixth. The tropical rain forest is a special cause for worry as it is a natural recycler, provider and protector for our planet. It recycles carbon, nitrogen and oxygen, helps determine temperature, rainfall and other climatic conditions and supports the most diverse ecosystem in the world. These unique habitats took 100 million years to develop and yet it’s taken just 40 years to destroy half of them. These forests in Amazonia, South-East Asia and West and Central Africa are being destroyed at an alarming rate of 42 million acres per year. Deforestation destroys topsoil, leaving large areas of land much less fertile. Besides, it could cause one forth of all species on Earth to vanish in the next 25 years and weather patterns to change.
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