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All these endangered species are listed in the Red lists.
The ozone layer and ozone hole
The ozone layer is a layer of gas high above the surface of the earth that helps to protect it from the sun’s ultraviolet radiation, which can damage our skin and cause cancer. Scientists have recently discovered holes in the ozone layer, caused by substances called CFCs (chlorofluorocarbons). CFCs are used in refrigerator, aerosol cans and in the manufacture of some plastic products. Some companies now make aerosols that don’t contain CFCs, and these are often marked ozone-friendly.
Factories, power stations and motor vehicles pump large amounts of carbon dioxide and other waste gases into the air. This is the major cause of the green house effect. A lot of petrol contains lead, which is very poisonous and can cause brain damage in children. Many people now prefer using unleaded petrol. Some poisonous gases dissolve in water in the atmosphere and then fall to the earth as acid rain. Acid rain damages trees and buildings, and can kill fish in lakes and rivers. Rivers can also be polluted by industrial waste from factories and chemical fertilizers and pesticides used by farmers.
There are several groups which try to protect the environment. The most famous group is Greenpeace which makes campaigns in many countries around world. They have made campaigns against hunting whales, pollution in the North Sea, nuclear power and testing of nuclear weapons and many others issues. Greenpeace supporters organize demonstrations and they also take direct actions. For example, they block pipes that pour pollution into the sea. Another important environmental group is Friends of the Earth. They have led campaigns against global warming, the destruction of the rain forests.
Most of energy we use today comes from coal, oil and gas. But these will not last forever and burning them is slowly harming the atmosphere. We need to look for other ways of supplying energy.
Solar power is a way of using the sun’s energy as heat or to make electricity. We can also use wind power by building modern windmills that spin in the wind. There are several types of water power: river water in mountains areas can be used for hydroelectric power, and we can also create electricity from sea water flowing in and out with the tides.
Recycling is the processing of used objects and materials so that they can be used again. About 60% of rubbish from homes and factories contain materials that could be recycled. Recycling saves energy and raw materials and also reduces damage to the country side. Glass, paper and aluminium cans can be recycled very easily.