Environmental Protection

Cudzie jazyky » Angličtina

Autor: janka
Typ práce: Referát
Dátum: 21.09.2008
Jazyk: Angličtina
Rozsah: 594 slov
Počet zobrazení: 5 180
Tlačení: 472
Uložení: 506
Praktické!
Civilization has brought people many advantages but its products also pollute and damage the environment in which we live. Britain has been implementing policies to protect the environment against pollution from industry and other sources for more than a century, while in the Czech Republic we are only at the beginning. Pollution affects air, water, land, forests, people, animals and plants.

Technology has an important role to play in reducing pollution and developing new means for reducing harmful emissions. It can be used to protect the environment in several ways, including basic changes which result in less waste or pollution and developing ways to recycle materials. Waste materials which were previously dumped can be converted into useful products. “End-of-pipe” systems can be installed to clean up emissions. And cleaner or less harmful alternative products may be manufactured.

Air pollution is the biggest problem in large cities and in areas with concentrated industrial production. Emissions range from smoke, dust, and smells to car and truck exhausts. Smoke contents sulphur dioxide, nitrogen oxide and carbon dioxide which are produced by coal-fired power stations and industrial plants burning fossil fuels. Substances, such as sulphur dioxide and nitrogen oxide can cause major changes in the environment which can lead to climate changes. These substances mix with water vapour in the atmosphere and form sulphuric acid and nitric acid. Sunlights turns these acids into poisonous oxidants which fall in the form of rain (acid rain) or snow onto trees and gradually kill them.

Trees are vitally important for our life because they are the lungs of our planet. They absorb carbon dioxide from the air and give out oxygen in return. In some parts of the world, such as Asia and South America, trees are not threatened by pollution, but by people. The great rain forests are being destroyed for firewood and building materials. Since the Amazon rain forest covers an area as large as the whole of Europe and contains one third of the world’s trees, scientists believe that it provides 50% of the world’s annual protection of oxygen. If we lose tropical forests, it will become more difficult, perhaps even impossible, to breathe.

With more carbon dioxide in the air, the temperature will rise; the icecaps at the North and South Poles will melt, and the sea level will rise which will result in the flooding of many coastal cities. Several gases have been identified as contributing to the “greenhouse effect”, which can also cause climate change. Without this geenhouse effect there could be no life on earth because the earth is warmed up naturally by the atmosphere which traps solar radiations. But manmade atmospheric emissions, such as carbon dioxide (produced by burning fossil fuels), nitrogen oxides (from car exhausts), chlorofluorocarbons from aerosol and refrigerators) and water vapour prevent the heat from escaping. The result is a rise in the Earth’s temperature, the melting of arctic ice and the flooding of areas situated near sea level.

Ozone is another air pollutant that contributes to the greenhouse effect at lower atmospheric levels. It is produced by the reaction of sunlight on car exhaust fumes and is a major air pollutant in hot summers. On the ground level ozone can cause asthma attacks and corrosion of certain materials. On the other hand, ozone forms a layer in the upper atmosphere which protects life on Earth from ultraviolet rays. These rays are a cause of skin cancer. A continent-sized hole has formad over Antarctica as a result of damage of the ozone layer, caused in part by chlorofluorocarbon.
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