Air pollution

The condition for the emergence and development of life on earth is the atmosphere - the gaseous medium surrounding the Earth. Its mass is about 2.15 * 1 015 tonnes, or less than one-millionth of the mass of the entire Earth. The thickness of the lower layer of the atmosphere (the troposphere), containing about 80% of its weight, from 8 km in high latitudes to 18 km in the equatorial belt. In the stratosphere, located 55 km above the surface is up to 20% by weight of the atmosphere. The dry air at the surface of the earth contains by volume 73% nitrogen and 21% oxygen, argon and small fractions of carbon dioxide. Due to the presence in the atmosphere of water vapor and carbon dioxide, it hardly transmits the heat radiation, creating a so-called " greenhouse effect." This helps to keep the heat at the surface and a higher temperature than it would be without enveloping the Earth atmospheric shell. The increase in carbon dioxide in the atmosphere as a result of human activity, combustion processes, which burn oxygen and releases carbon dioxide and other gases, leads to increased " greenhouse effect" may cause a rise in the average temperature, the melting of polar ice threatens. In the composition of the atmosphere adversely affects release of various other pollutants - sulfur oxides, nitrogen oxides, hydrocarbons, particulate matter (dust), and others. The most polluting vehicles, mainly car - the main source of carbon monoxide, hydrocarbons and nitrogen oxides. Overall, it accounts for over half of all emissions. The major source of pollution - power plants emitting sulfur oxides, nitrogen oxides and dust; hereinafter - the industry which produces carbon dioxide, sulfur oxides, hydrocarbons and particulates. Other sources pollute the atmosphere largely carbon dioxide, hydrocarbons, particulate matter. Air pollution Production sector has diversified reverse harmful effects on the production and life of people. Particularly heavily polluted atmosphere in the developed countries. Industrial areas of the United States released into the air is a large number of pollutants (measured in millions of tones per year), that if it were not for the movement of air from the ocean over the continent of America, the effects of such pollution would be very heavy. Quite adversely affects it in those cities where air circulation is low. For example, in New York, Los Angeles, Tokyo, London, windless days breathing hard, increasing morbidity and mortality from bronchitis, asthma, emphysema, cardiovascular disease. A particularly heavy toll on the health of the connection of smoke and fog - smog (smoke fog). Mortality from lung cancer is higher in urban than in rural areas.