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Air Quality

Air Quality. What is this in the air?. People have euphemisms for smog; sometimes it's fog, sometimes it's haze. It's hard to know sometimes whether the air is full of something natural, like water vapor, or something man-made, like ozone.

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Air Quality

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  1. Air Quality

  2. What is this in the air? • People have euphemisms for smog; sometimes it's fog, sometimes it's haze. It's hard to know sometimes whether the air is full of something natural, like water vapor, or something man-made, like ozone. • But in cities like this the air is often being marred by air pollution.

  3. Air Quality • Pollutants include materials that are naturally occurring but are added to the atmosphere so that they are there in larger quantities than normal. • Pollutants may also be human-made compounds that have never before been found in the atmosphere. • Pollutants dirty the air, change natural processes in the atmosphere, and harm living things.

  4. Problem with Air Quality • Air pollution started to be a problem when early people burned wood for heat and cooking fires in enclosed spaces such as caves and small tents or houses. • But the problems became more widespread as fossil fuels such as coal began to be burned during the Industrial Revolution.

  5. Smog • Smog refers to a noxious mixture of gases and particles that often appears as a haze in the air. It has been linked to a number of adverse effects on health and the environment. • The two primary pollutants in smog are ground-level ozone (O3) and particulate matter (PM) • Smog has been identified as contributing factors in thousands of premature deaths across the country each year, as well as increased hospital visits, doctor visits and hundreds of thousands of lost days at work and school.

  6. Photochemical Smog • Photochemical smog, a different type of air pollution, first became a problem in Southern California after World War II. • The abundance of cars and sunshine provided the perfect setting for a chemical reaction between some of the molecules in auto exhaust or oil refinery emissions and sunshine. • Photochemical smog consists of more than 100 compounds, most importantly ozone. Smog over Los Angeles as viewed from the Hollywood Hills

  7. The Clean Air Act of Canada • The original Clean Air Act passed in 1970 and has been modified and added to ever since. • The goal of this act is to reduce greenhouse emissions by 45 to 65 percent by 2050, according to the government of Canada.

  8. Misconceptions • It is not a law by itself. The act is what’s known as “enabling legislation” that strengthens existing laws. • The Canadian government believes that the Clean Air Act is the best way to strengthen the Canadian Environmental Protection Act. • Considerations • The Clean Air Act allows the Canadian government to move industry from voluntary compliance to strict enforcement of emission standards. • The act also lets the Canadian government establish clear national standards and institute a holistic approach that takes care of emissions and economic concerns.

  9. Poor air quality causes thousands of deaths each year and hundreds of thousands of asthma episodes. • Sometimes during summer and winter months Canadians are told not to leave their homes because of smog warnings. • Effects • The act amends the Energy Efficiency Act to require energy-using projects traded between provinces to comply with energy efficiency standards and the Motor Vehicle Fuel Consumption Standards Act. • The Clean Air Act also provides the Canadian government with the authority to set strict regulations regarding air pollutants and greenhouse gas.

  10. Regional Air Quality • Air quality in a region is not just affected by the amount of pollutants released into the atmosphere in that location but by other geographical and atmospheric factors. • Winds can move pollutants into or out of a region and a mountain range can trap pollutants on its leeward side. • Inversions commonly trap pollutants within a cool air mass. If the inversion lasts long enough, pollution can reach dangerous levels.

  11. Pollutants remain over a region until they are transported out of the area by wind, diluted by air blown in from another region, transformed into other compounds, or carried to the ground when mixed with rain or snow. • This tablebelow lists the smoggiest cities in 2011: eight of the 10 are in California. Why do you think California cities are among those with the worst air pollution? The state has the right conditions for collecting pollutants including mountain ranges that trap smoggy air, arid and sometimes windless conditions, agriculture, industry, and lots and lots of cars.

  12. In Summary… • Air is polluted by natural compounds in unnatural quantities or by unnatural compounds. • Some pollutants enter the air directly and others are created by chemical reactions, such as those that are part of photochemical smog. • Regions that are chronically polluted experience the release of a lot of pollutants into the air. The effects of pollution may also be amplified by geographical and atmospheric factors. https://www.youtube.com/watch?v=R_pb1G2wIoA

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