One form of environmental degradation is air pollution.
History of Air Pollution
Humans probably first experienced harm from air pollution when they built fires in poorly ventilated caves. Since then we have gone on to pollute more of the earth's surface. Until recently, environmental pollution problems have been local and minor because of the Earth's own ability to absorb and purify minor quantities of pollutants. The industrialization of society, the introduction of motorized vehicles, and the explosion of the population, are factors contributing toward the growing air pollution problem. At this time it is urgent that we find methods to clean up the air.
The primary air pollutants found in most urban areas are carbon monoxide, nitrogen oxides, sulfur oxides, hydrocarbons, and particulate matter (both solid and liquid). These pollutants are dispersed throughout the world's atmosphere in concentrations high enough to gradually cause serious health problems. Serious health problems can occur quickly when air pollutants are concentrated, such as when massive injections of sulfur dioxide and suspended particulate matter are emitted by a large volcanic eruption.
Carbon dioxide, a greenhouse gas, is the main pollutant that is warming Earth. Though living things emit carbon dioxide when they breathe, carbon dioxide is widely considered to be a pollutant when associated with cars, planes, power plants, and other human activities that involve the burning of fossil fuels such as gasoline and natural gas. In the past 150 years, such activities have pumped enough carbon dioxide into the atmosphere to raise its levels higher than they have been for hundreds of thousands of years.
Industrialized countries have worked to reduce levels of sulfur dioxide, smog, and smoke in order to improve people's health. But a result, not predicted until recently, is that the lower sulfur dioxide levels may actually make global warming worse. Just as sulfur dioxide from volcanoes can cool the planet by blocking sunlight, cutting the amount of the compound in the atmosphere lets more sunlight through, warming the Earth. This effect is exaggerated when elevated levels of other greenhouse gases in the atmosphere trap the additional heat.
Most people agree that to curb global warming, a variety of measures need to be taken. On a personal level, driving and flying less, recycling, and conservation reduces a person’s "carbon footprint"—the amount of carbon dioxide a person is responsible for putting into the atmosphere.
The sources of air pollution are both natural and human-based. As one might expect, humans have been producing increasing amounts of pollution as time has progressed, and they now account for the majority of pollutants released into the air.
Case Study: Air Pollution in
According to the World Bank 16 of the worlds’s 20 cities with the worst air are in
The air pollution and smog in
Coal is the number once source of air pollution in
Effects of Air Pollution in China
The engines of Chinese airlines have to be overhauled and replaced more frequently than elsewhere because operating in Chinese air corrodes the turbine blades faster.
The Beijing Coking-Chemical Plant was one of the
Public health is reeling. Pollution has made cancer
“It is a very awkward situation for the country because our greatest achievement is also our biggest burden,” says Wang Jinnan, one of
But pollution poses its own threat. Officials blame fetid air and water for thousands of episodes of social unrest. Health care costs have climbed sharply. Severe water shortages could turn more farmland into desert. And the unconstrained expansion of energy-intensive industries creates greater dependence on imported oil and dirty coal, meaning that environmental problems get harder and more expensive to address the longer they are unresolved.
The government has numerical targets for reducing emissions and conserving energy. Export subsidies for polluting industries have been phased out. Different campaigns have been started to close illegal coal mines and shutter some heavily polluting factories. Major initiatives are under way to develop clean energy sources like solar and wind power. And environmental regulation in
Health Problems and Air Pollution in China
Washington Post writer John Pomfret was based in
It has been reasoned that all forms of air pollution are 10 times more damaging to health than all forms of water pollution. According to the World Bank and WHO between 300,000 and 350,000 people die from outdoor air pollution and about 300,000 die from inside air pollution. Some think the true figure is much higher. Some estimate that indoor air pollution kills more than 700,000 people a year. The fine particles produced by coal-fired stoves exacerbates respiratory problems and is especially damaging to children’s lungs functions.
Air pollution causes premature births, low-birth weight babies, and depresses lungs functioning in otherwise healthy people. It has also been blamed for
Air pollution is also linked with a variety of respiratory aliments. Around some factories the asthma rate is 5 percent. It is estimated that 26 percent of all deaths in
Air pollution is believed to have significantly reduced crop production. Studies based on satellite imagery and ground-based observation suggest that particles of suspended pollutants scatter sun light over two thirds of eastern China resulting in harvests of rice and winter wheat that may be 5 to 30 percent less than if there was no pollution.
Combating Air Pollution in China
To reduce air pollution in
In
Bibliography:
http://environment.nationalgeographic.com/environment/global-warming/pollution-overview.html
http://healthandenergy.com/air_pollution_causes.htm
http://library.thinkquest.org/26026/Environmental_Problems/air_pollution.html
http://www.buzzle.com/articles/environmental-degradation.html
http://factsanddetails.com/china.php?itemid=392&catid=10&subcatid=66
http://www.wri.org/publication/content/8416
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