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Environmental protection

The planet Earth is only a tiny part of the universe, but it's the only place where human beings can live. People always polluted their surroundings. But until now pollution was not such a serious problem. People lived in uncrowded rural areas and did not have pollution – caused by machines. With the development of crowded industrial cities, which created huge amounts of pollutants, the problem has become more important. Today our planet is in serious danger. Acid rains, global warming, air and water pollution, and overpopulation are the problems that threaten human life on Earth. Our forests are disappearing because they are cut down or burnt. If this trend continues, one day we won't have enough oxygen to breathe.

The seas are in danger. They are filled with poison: industrial and nuclear wastes, chemical fertilizers and pesticides. The Mediterranean is already nearly dead; the North Sea is following its fate. The Aral Sea is about to disappear. If nothing is done about it, one day nothing will be able to live in the seas. Every ten minutes one kind of animal, plant or insect dies out forever. If nothing is done about it, one million species that are alive today may soon become extinct. Air pollution is another serious problem. In Cairo just breathing the air is dangerous – equivalent to smoking two packs of cigarettes a day. The same holds true for many Russian cites.

Factories emit tons of harmful chemicals. These emissions have disastrous consequences for our planet. They are the main reason for the greenhouse effect and acid rains.

And even greater threat are nuclear power stations. We all know how tragic the consequences of the Chernobyl disaster are.

Fortunately, it's not too late to solve these problems. We have the time, the money and even the technology to make our planet a better, cleaner and safer place. We can plant trees and create parks for endangered species. We can recycle litter. Individuals and groups of people can work together to persuade enterprises to stop polluting activities.

Greenpeace

In 1971, motivated by their vision of a green and peaceful world, a small team of activists set sail from Vancouver, Canada, in an old fishing boat. These activists, the founders of Greenpeace, believed a few individuals could make a difference.

Their mission was to «bear witness» to US underground nuclear testing at Amchitka, a tiny island off the West Coast of Alaska, which is one of the world's most earthquake-prone regions. Amchitka was the last refuge for 3000 endangered sea otters, and home to bald eagles, peregrine falcons and other wildlife. Even though their old boat, was intercepted before it got to Amchitka, the journey sparked a flurry of public interest. The US still detonated the bomb, but the voice of reason had been heard. Nuclear testing on Amchitka ended that same year, and the island was later declared a bird sanctuary.

Today, Greenpeace is an international ecological organization that has 2.8 million supporters worldwide, and national as well as regional offices in 41 countries. Its headquarters are based in Amsterdam, the Netherlands.



Greenpeace is a non-profit organization and nongovernmental. It unites people of different colours living in different continents and speaking different languages. The common mission of this organization is preserving life on the earth in its full variety.

Greenpeace does not accept donations from governments, corporations or political parties but relies on contributions from individual supporters and foundation grants. Greenpeace does not support any political party. Nevertheless, its members carry on a dialogue with all political forces and struggle for approving and passing laws for the welfare of our environment.

As a global organization, Greenpeace focuses on the most crucial worldwide threats to our planet's biodiversity and environment. It campaigns to stop climate change, save the oceans, stop whaling, say no to genetic engineering, stop the nuclear threat, eliminate toxic chemicals.

The goal of Greenpeace is to expose environmental criminals, and to challenge government and corporations when they fail to live up to their mandate to safeguard our environment and our future.

Ozone Layer

Ozone layer or ozonosphere, region of the stratosphere containing relatively high concentrations of ozone , located at altitudes of 12-30 mi (19-48 km) above the earth's surface. Ozone in the ozone layer is formed by the action of solar ultraviolet light on oxygen.

The ozone layer prevents most ultraviolet (UV) and other high-energy radiation from penetrating to the earth's surface but does allow through sufficient ultraviolet rays to support the activation of vitamin D in humans. The full radiation, if unhindered by this filtering effect, would destroy animal tissue. Higher levels of radiation resulting from the depletion of the ozone layer have been linked with increases in skin cancers and cataracts and have been implicated in the decline of certain amphibian species.

In 1974 scientists warned that certain industrial chemicals, e.g., chlorofluorocarbons (CFCs) and to a lesser extent, halons and carbon tetrachloride, could migrate to the stratosphere. There, sunlight could free the chlorine or bromine atoms to form chlorine monoxide or other chemicals, which would deplete upper-atmospheric ozone. A seasonal decrease, or "hole," discovered in 1985 in the ozone layer above Antarctica was the first confirmation of a thinning of the layer. The hole occurs over Antarctica because the extreme cold helps the very high clouds characteristic of that area form tiny ice particles of water and nitric acid, which facilitate the chemical reactions involved. In addition, the polar winds, which follow a swirling pattern, create a confined vortex, trapping the chemicals. When the Antarctic sun rises in August or September and hits the trapped chemicals, a chain reaction begins in which chlorine, bromine (from the halons), and ice crystals react with the ozone and destroy it very quickly. The effect usually lasts through November. There is a corresponding hole over the Arctic that similarly appears in the spring, although in some years warmer winters there do not result in a major depletion of the ozone layer. A global thinning of the ozone layer results as ozone-rich air from the remaining ozone layer flows into the ozone-poor areas.

Minimum ozone levels in the Antarctic decreased steadily throughout the 1990s, and less dramatic decreases have been found above other areas of the world. In 2000 (and again in 2003) the hole reached a record size, extending over 10.8 million sq mi (28 million sq km), an area greater than that of North America. In 1987 an international agreement, the Montreal Protocol , was reached on reducing the production of ozone-depleting compounds. Revisions in 1992 called for an end to the production of the worst of such compounds by 1996, and CFC emissions dropped dramatically by 1993. Recovery of the ozone layer, however, is expected to take 50 to 100 years. Damage to the ozone layer can also be caused by sulfuric acid droplets produced by volcanic eruptions.


Date: 2015-12-11; view: 209


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