Conformity Iowa State Uiversityconformity爱荷华州立大学.pptVIP

Climate Change ? Certain gases in the troposphere absorb some of the infrared radiation reflected from the earth ? Carbon Dioxide is the major one (50%). ? Others include methane (18%) and CFCs (14%). CFCs also are responsible for destroying the stratospheric ozone layer ? The United States produces over 20% of the worlds greenhouse gases Fundamentals of Air Pollution and Motor Vehicle Emissions John T. White, EPA TheExtentofAirPollutionToday Overall, 54 million metric tons from mobile sources in 1990 (43% of total) Mobile Sources Stationary Sources CO VOCs NOx SO 2 Lead PM 10 Fundamentals of Air Pollution and Motor Vehicle Emissions John T. White, EPA Who isAffected byAir Pollution? 63 22 9 19 1 5 Ozone CO NO2 PM10 SO2 Lead Millions of people living in counties with air quality that exceeds each NAAQS (1990 data) Over 74 million people are subjected to high levels of at least one of these pollutants Fundamentals of Air Pollution and Motor Vehicle Emissions John T. White, EPA World wide WHO indicates that 2.4 million people die from causes directly attributable to air pollution More than for car accidents Visibility Although not a pollutant, visibility is a major pollution concern Haze Smog Air Toxics Get information from EPA Example - /otaq/toxics.htm When is it a problem Classified as pollutant once their presence results in damage to humans, plants, animals or materials Concentration 1 volume of gaseous pollutant = 1 ppm 106 volumes (pollutant + air) 0.0001 percent by volume = 1 ppm * * * * * * * * * * * * * * * * * * * * * * * * * Effects and Sources of Air Pollutants CE 524 January 2011 Slides noted as AWMA are from: Understanding Air Quality from the Air and Waste Management Association Do not make copies of these slides for distribution Major Provisions of 1970 CAAA Established NAAQS Primary – allows adequate margin of safety to protect public health Secondary – protects public from effects of air pollution Plants, animals, vis