1Chapter 13Air PollutionChapter Outline•Historical Perspective•Sources and Types of Air PollutionSmog•Trends in Air Quality•Meteorological Factors Affecting •Acid PrecipitationSigns of prosperityAir Pollution – Meteorology•weather conditions influence the dilution and dispersal of air pollutants•air pollution effects weather and climate2Air Pollution – Meteorology•Air Pollution Episodes or Eventsoften occur when there is no major change in the output of contaminants•Quantity of contaminants emitted into the atmosphere•Atmospheric conditions promote pollution eventsAir Pollution: continuing threat to our health and welfare•Average adult male•30 lbs of air/day•2.6 lbs of food/day•4.4 lbs of water/day3Dust Bowl, Kansas 1937Historical Perspective•Air is never perfectly clean•Natural sources of pollution have always existed(ash, salt particles, pollen, spores, smoke from forest and brush fires, wind blown dust etc.)•Humans accentuate natural pollution• Tribes were partly nomadic to get away from their wastes-animal, vegetable and human• Fire without chimneys• Products of incomplete combustion inside living quartersHistorical EpisodesBefore the Industrial Revolution4• Chimney removed combustion products from inside to outside• 61 A.D. Rome; Philosopher Seneca: “as soon as I had gotten out of the heavy air of Rome and the stink of the smoky chimneys…which poured forth ..pestilential vapors and soot…I felt an alteration of my dispositionHistorical EpisodesBefore the Industrial Revolution• 1784—Watt’s steam engine; boilers to burn fossil fuels (coal) to make steam to pump water and move machinery• Smoke and ash from fossil fuels by powerplants, trains, ships: coal (and oil) burning = smoke, ash• British Parliament studies 1819 1843 1848 1866 1875= lots of dirty air, nothing was doneHistorical EpisodesThe Industrial Revolution5Smoke Abatement Era-U.S. 1880-1940’s• No penalties for violations in early laws• Smoke abatement ordinances, stricter laws starting in 1940’s with penalties• Natural gas = clean fuel• A. Ore Smelting Era 1900-1930’s CuS + O2= Cu +SO2(SO3) same for Pb, Zn and Ni (pollutant)• B. 1900—Electricity (Powerplant) + CARSDisaster Era—1930’s--???• A. Meuse Valley, Belgium, 1930•1stmodern air pollution disaster• River valley, densely populated• Highly industrialized• Winter, high barometric pressure• Thermal temperature inversion6Meuse Valley, Belgium, 1930• 63 died (mostly elderly)• Sore throats, shortness of breath, cough, phlegm, nausea, vomiting•SO2, sulfur dioxide•H2O•SO4sulfuric acid mist• Cattle, birds and rats died• Got little news coverageDonora, Pennsylvania—Oct. 1948• Monongahela River Valley• Industrial town—steel mill, sulfuric acid plant, freight yard, etc.• Population—14,000• Steep hills surrounding the valley• Oct 26—temperature inversion (warm air trapping cold air near the ground)• Stable air, fog, lasted 4.5 days71. 6000 people became ill2. 20 people died3. U.S. Public Health Service called in– first time air pollution officially recognized as potential public health problem4. Sulfur gases + particulates, sulfuric acid mistDonora, Pennsylvania—Oct. 1948Historical EpisodesLondonDecember 19525-day event4000 deadAdditional events in 53 and 62Combination of unusually cold period, coal burning, and stable atmospheric conditions under a high pressure system8Historic smog death toll risesaken from the BBC: Thursday, 5 December, 2002 Officials believe that as many as 12,000 people may have died in the great London smog of 1952. Death toll "The interesting thing is that no one realized at the time that the no of deaths were increasing," he told the BBC. "There weren't bodies lying around in the street and no one really noticed that more people were dying.""One of the first indications was that undertakers were running out of coffins and florists were running out of flowers. The number of deaths per day during and just after that smog were three to four times the normal."9World-wide Air Pollution Episode• November 27-December 10, 1962• Thousands of excess deaths in many cities including NYC, London, Boston, ParisBhopal, India Dec. 3, 1984• Union Carbide pesticide plant leak kills up to 2,000 with up to 350,000 injured and 100,000 with permanent disabilities• Methyl isocyanate (MIC)—used as an intermediary in manufacture of Sevin(Carbaryl)• CO + Cl = phosgene• Phosgene + methylamine = MIC• MIC—irritant to the lungs---edema, fluid (cause of death, bronchospasms, corneal opacity• Hydrogen cyanide?• Sabotage or industrial accident?10Similarities among Disasters• Winter months• Dense population• Heavy industrialization•Often valley• Temperature inversion• Stagnant air• Accident, or mixtures from non-accidentsSources and Types of Air PollutionAir pollutants: airborne particles and gasses that occur in concentrations that endanger the health and well-being of organisms or disrupt the orderly functioning of the environmentPrimary pollutants: emitted directly from identifiable sourceSecondary pollutants: produced in the atmosphere through chemical reactions11Sources and Types of Air PollutionPrimary pollutants:Point sources factories, power plantsMobil sources transportation, lawn mowers etc.Biogenic sources all nonanthropogenic sources (trees, vegetation, gas seeps etc.)Area sources small and individual sources (dry cleaners)12Sources and Types of Air PollutionPrimary pollutants1. Particulate matter:• solid particles and liquid droplets found in air• Fine particles (PM2.5) = combustion (fuel, wood)• Coarse particles (PM10) = aeolian (wind blown), crushing/grinding processes• Most obvious form of air pollution (reduce visibility, leave film on surfaces)13Primary pollutants2. Sulfur Dioxide (SO2):• Colorless, corrosive gas• Combustion of sulfur-containing fuels (coal, oil)• Acid precipitation (H2SO4)• Reduced lung function (short-term exposure)Primary pollutants3. Nitrogen Oxides (NOx):• High-temperature Combustion (power plants, motor vehicles)• Acid precipitation (HNO3)• Smog Formation14Primary pollutants4. Volatile Organic Compounds (VOC):• Hydrocarbons (carbon and hydrogen)• Methane (CH4)• Incomplete combustion of gasoline• React with NOxto form secondary pollutantsPrimary pollutants5. Carbon Monoxide (CO):• Colorless, odorless,