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Oil: for and against



Oil is the world's most popular source of energy and is the world's most important trading commodity. Petrol has many advantages as a fuel. There is a plentiful supply of oil with enough to last for another fifty to a hundred years. Having said that, oil is a finite source of energy. This means that there is only a certain amount of it in the ground to extract. Many people predict that, unless energy is conserved or much more oil is discovered, the present world's oil supply could be used up by the end of the 21s' century. It is a relatively clean fuel to burn. It gives off few fumes or smoke and so to a certain extent may be considered environment-friendly.

There have, however, been numerous infamous occasions of catastrophic oil spills from damaged ships at sea which create great environmental pollution. As a result coastal wildlife, such as seagulls, are killed and beaches are damaged. It is an efficient fuel which gives off great heat when burnt. It is easy to handle and transport. Huge oil tankers can transport millions of litres at a time. It is easily stored in domestic tanks and is piped directly to domestic burners in people's homes. Numerous by-products such as synthetic fabrics, paint, dyes and other chemicals are manufactured from oil.

Population growth

In the past, the world's population fluctuated. War, famine, plagues like the Black Death, and lack of medicine prevented rapid population growth. It is estimated that the population of the world in 9000 ВС was about ten million. At this time people wandered from place to place in search of wild cereals. Then, people in Mesopotamia (present-day Iraq) discovered that by using seeds from wild cereals and scattering them in a fertile area they would grow, flourish and produce crops for food. This eliminated their need to wander and so they became the first farmers.

The discovery and spread of agriculture led to a speeding up of population growth. Initially population growth was slow. When Christ was born there were about 260 million people on Earth. Growth rates continued to fluctuate because of war, famine and other natural disasters. It took the next 1,700 years for the world's population to double to 520 million. However, from 1750 onwards the world's population grew faster than before. Around then, new farming methods in Europe such as the development of better breeds of animals and the use of new farm machines, led to a large increase in food production. The invention of the steam engine provided employment for thousands of workers in coalfield areas in Europe. At this time hygiene and medical knowledge also improved. Europeans were healthier, lived longer and had more children than before. They conquered new lands in the colonies, which increased land for agriculture. So the world's population grew faster than ever. Throughout the twentieth century the world's population grew so fast that it was called a population explosion.







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