Air Pollution Essay Research Paper INTRODUCTION Air

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Air Pollution Essay, Research Paper INTRODUCTION Air Pollution, addition of harmful substances to the atmosphere resulting in damage to the environment, human health, and quality of life. One of many forms of pollution, air pollution occurs inside homes, schools, and offices; in cities; across continents; and even globally. Air pollution makes people sick it causes breathing problems and promotes cancer and it harms plants, animals, and the ecosystems in which they live. Some air pollutants return to earth in the form of acid rain and snow, which corrode statues and buildings, damage crops and forests, and make lakes and streams unsuitable for fish and other plant and animal life.In a cities, most air pollution comes from one human activity: burning fossil fuels natural gas,

coal, and oil to power industrial processes and motor vehicles. Between 1900 and 1970, motor vehicle use rapidly expanded, and emissions of nitrogen oxides, some of the most damaging pollutants in vehicle exhaust, increased 690 percent. When fuels are incompletely burned, various chemicals called volatile organic chemicals (VOCs) also enter the air. Pollutants also come from other sources. For instance, decomposing garbage in landfills and solid waste disposal sites emits methane gas, and many household products give off VOCs.Once in the atmosphere, pollutants often undergo chemical reactions that produce additional harmful compounds. Air pollution is subject to weather patterns that can trap it in valleys or blow it across the globe to damage pristine environments far from the

original sources.SMOG AND ACID PRECIPITATION Smog is intense local pollution usually trapped by a thermal inversion. Before the age of the automobile, most smog came from burning coal and was so severe that in 19th-century London, streetlights were turned on by noon because soot and smog darkened the midday sky. Burning gasoline in motor vehicles is the main source of smog in most regions today. Ozone in the lower atmosphere is a poison it damages vegetation, kills trees, irritates lung tissues, and attacks rubber. Environmental officials measure ozone to determine the severity of smog. When the ozone level is high, other pollutants, including carbon monoxide, are usually present at high levels as well.In the presence of atmospheric moisture, sulfur dioxide and oxides of nitrogen

turn into droplets of pure acid floating in smog. These airborne acids are bad for the lungs and attack anything made of limestone, marble, or metal. In cities around the world, smog acids are eroding precious artifacts, including the Parthenon temple in Athens, Greece, and the Taj Mahal in Agra, India. Oxides of nitrogen and sulfur dioxide pollute places far from the points where they are released into the air. Carried by winds in the troposphere, they can reach distant regions where they descend in acid form, usually as rain or snow. Such acid precipitation can burn the leaves of plants and make lakes too acidic to support fish and other living things.Smog spoils views and makes outdoor activity unpleasant. For the very young, the very old, and people who suffer from asthma or

heart disease, the effects of smog are even worse: It may cause headaches or dizziness and can cause breathing difficulties. In extreme cases, smog can lead to mass illness and death, mainly from carbon monoxide poisoning. In 1948 in the steel-mill town of Donora, Pennsylvania, intense local smog killed nineteen people. In 1952 in London over 3000 people died in one of the notorious smog events known as London Fogs; in 1962 another 700 Londoners died.With stronger pollution controls and less reliance on coal for heat, today s chronic smog is rarely so obviously deadly. However, under adverse weather conditions, accidental releases of toxic substances can be equally disastrous. The worst such accident occurred in 1984 in Bhopal, India, when methyl isocyanate released from an