Acid Rain

Acid rain is caused by serious air pollution from power stations, factories and cars. When we bum fuels like coal and oil, they give off a mixture of chemicals, mainly sulphur dioxide and nitrogen oxides. If enough of these chemicals escape into the atmosphere they combine to form a dangerous pollution which then returns to Earth. Industrial countries like Britain now not only pollute themselves, but they also "export" pollution to other countries.

In the early 1900's, the fish population of Norway's lakes began to decline. It was later discovered that lake water had become so acidic that many species of plants and animals could no longer survive. Now, the situation is even worse. By 1982, Norway had 5 000 lakes which were acidic. Of those, 1 750 had no fish in them. In thousands of lakes in Europe and North America this tragedy has been repeated. Fish can no longer survive in such an environment.

When the water that we use for drinking contains a high level of acid, it can dissolve water pipes. In Glasgow, Scotland, old lead water pipes and tanks were dissolved by the acid, so that people were drinking dangerously high levels of lead. This was particularly serious in the case of young children because it is now widely known that lead poisoning at an early age can affect the brain.

Scientists realized in the 1960's that acid rain was causing great damage to lakes, but it was not until the 1970's that they saw the link between that type of pollution and the death of large numbers of trees. By 1987, forests throughout the whole Europe were in decline. Trees lost their leaves and could not grow at a normal healthy rate.

Short Answer Questions

1. What causes acid rain?
2. Acid rain contains ____.
3. In Norway, 5 000 lakes were acidic. Among these, how many still had fish in them?
4. Why is acid rain particularly harmful for young children?
5. The word "This" in Paragraph 3 refers to ____.

(Keys.)