Экологические проблемы в современном мире.

Sunlight gives us heat. Some of the heat warms the atmosphere and some of the heat goes back into space. Nowadays the air surrounding the earth has become much warmer because the heat can’t go back into space. That’s why winter and summer temperatures in many places have become higher. During the last 100 years people have produced a lot of carbon dioxide. This gas in the atmosphere works like glass in a greenhouse. It let’s the heat get in, but doesn’t let get out. So the atmosphere becomes warmer.

What is the main reason for the greenhouse effect?

Every year more and more plants and animals disappear never to be seen again. In many lakes the fish are dying. Scientists are beginning to get worried. What is killing the fish?

The problem is acid rain. Acid rain is a kind of air pollution. It is caused by factories that burn coal or oil or gas. These factories send smoke high into the air. The wind often carries the smoke far from the factories. Some of the harmful substances in the smoke may come down with the rain hundreds of miles away. The rain in many places isn't natural and clean any more. It's full of acid chemicals. When it falls in lakes, it changes them too. Acid water is like vinegar or lemon juice. It hurts when it gets in your eyes. It also kills the plants and animals that usually live in lake water. That is why the fish are dying in lakes. Scientists are finding other effects of acid rain. In some large areas trees are dying. Not just one tree here and there, but whole forests. At first scientists couldn't understand why. There were no bugs or diseases in these trees. The weather was not dry. But now they think that the rain was the cause. Acid rain is making the earth more acidic in these areas. Some kinds of trees cannot live in the soil that is very acidic.

Antarctica: The World Park.

In the summer the human population of Antarctica goes up to 2.500. In the winter, there are only 700 human beings on the whole continent. It is the last great “empty “ place on earth and people in many countries are beginning to think that it must stay that way. They want Antarctica to be a world park: a place where nature will stay free of pollution and the changes that human beings bring. Many people want to keep Antarctica in its natural state, free of too many humans and animals from the outside.

The total area of Antarctica is 13,600,000 square kilometers. This is bigger than the U.S.A. and Mexico together, and nearly twice the size of Australia. Here you can find the coldest place on Earth: the temperature at the Russian Vostok station can go down to 88° centigrade. Ninety- eight per cent of the mainland of Antarctica is under over one kilometer thick.

Antarctica has 188 million birds. Ninety per cent of these are penguins. Two-thirds of the world's seals live in Antarctica.

People didn't know about the continent of Antarctica until 1840. No human walked on the mainland until 1895.

There is oil under Antarctic waters and coal under the mountains. There are also many kinds of metals. But now there is an agreement between the world's most powerful industrial countries that they will not exploit Antarctica's oil and minerals for at least fifty-five years.

Scientists say that if there is mining and drilling for oil in Antarctica it will have bad effects on the world’s weather.

Antarctica is the only continent on Earth where countries cannot take nuclear weapons. Visitors to Antarctica say it is extremely beautiful. One day you may visit the icy continent as a tourist. Some ordinary people already go there by ships.

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