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Air Pollution, Climate Change and Ozone Depletion General Information

Atmospheric pressure (millibars) Temperature Pressure Thermosphere Mesopause Heating via ozone Mesosphere Altitude (kilometers) Altitude (miles) Stratopause Stratosphere Tropopause Ozone “layer” Heating from the earth Troposphere Pressure = 1,000 millibars at ground level (Sea level) Temperature (˚C) Fig. 19-2, p. 440

The Earth’s Atmosphere Troposphere • Nitrogen, Oxygen, Carbon Dioxide, Water Vapor • Location of Earth’s weather • Temperature decreases with altitude

Stratosphere • Temperature increases with altitude • Contains 1000x the ozone of the rest of the atmosphere • 99% of ultraviolet radiation (especially UV-B) is absorbed by the stratosphere

Mesosphere The temperature decreases with increasing altitude

Thermosphere • Temperature increases with increasing altitude • Very high temperatures

Pollution in the atmosphere • Primary Pollutants – methane, ozone, dust particles, microorganisms, and chlorofluorocarbons (CFC’s) • Causes of Primary Pollutants – factories, cars, wind and soil, volcanoes, forest fires, pollen, decaying plants, salt particles from the sea, and refrigerants.

AIR POLLUTION • Some primary air pollutants may react with one another or with other chemicals in the air to form secondary air pollutants. Figure 19-3

Temperature Inversions • Cold, cloudy weather in a valley surrounded by mountains can trap air pollutants (left). • Areas with sunny climate, light winds, mountains on three sides and an ocean on the other (right) are susceptible to inversions. Figure 19-5

ACID DEPOSITION • Compounds in the atmosphere react to produce acidic chemicals that can travel long distances before returning to the earth’s surface. • Tall smokestacks reduce local air pollution but can increase regional air pollution.

Wind Transformation to sulfuric acid (H2SO4) and nitric acid (HNO3) Windborne ammonia gas and particles of cultivated soil partially neutralize acids and form dry sulfate and nitrate salts Wet acid depostion (droplets of H2SO4 and HNO3 dissolved in rain and snow) Nitric oxide (NO) Sulfur dioxide (SO2) and NO Dry acid deposition (sulfur dioxide gas and particles of sulfate and nitrate salts) Acid fog Farm Lakes in shallow soil low in limestone become acidic Ocean Lakes in deep soil high in limestone are buffered Fig. 19-6, p. 448

ACID DEPOSITION • pH measurements in relation to major coal-burning and industrial plants. Figure 19-7

ACID DEPOSITION • Acid deposition contributes to chronic respiratory disease and can leach toxic metals (such as lead and mercury) from soils and rocks into acidic lakes used as sources for drinking water.

ACID DEPOSITION Figure 19-8

ACID DEPOSITION • Air pollution is one of several interacting stresses that can damage, weaken, or kill trees and pollute surface and groundwater. Figure 19-9

Solutions Acid Deposition Prevention Cleanup Reduce air pollution by improving energy efficiency Add lime to neutralize acidified lakes Reduce coal use Add phosphate fertilizer to neutralize acidified lakes Increase natural gas use Increase use of renewable energy resources Burn low-sulfur coal Remove SO2 particulates & NOx from smokestack gases Remove NOx from motor vehicular exhaust Tax emissions of SO2 Fig. 19-10, p. 452

Air Quality is better in US; EPA estimates since 1970 • Particulate Matter (PM)- down 78% • Carbon Dioxide (CO2)- down 23% • Nitrogen Dioxide (Nox)- up 14% • Lead (Pb)- down 98% • Sulfur Dioxide (SO2)- down 32% Air quality is worse in developing countries: Mexico City & Beijing: air exceeds WHO standards 350 days/year

INDOOR AIR POLLUTION • Indoor air pollution usually is a greater threat to human health than outdoor air pollution. • According to the EPA, the four most dangerous indoor air pollutants in developed countries are: • Tobacco smoke. • Formaldehyde. • Radioactive radon-222 gas. • Very small fine and ultrafine particles.

Para-dichlorobenzene Chloroform Tetrachloroethylene Formaldehyde 1, 1, 1- Trichloroethane Styrene Nitrogen Oxides Benzo-a-pyrene Particulates Tobacco Smoke Radon-222 Asbestos Carbon Monoxide Methylene Chloride Fig. 19-11, p. 453

INDOOR AIR POLLUTION • Household dust mites that feed on human skin and dust, live in materials such as bedding and furniture fabrics. • Can cause asthma attacks and allergic reactions in some people. Figure 19-12

Case Study: Radioactive Radon • Radon-222, a radioactive gas found in some soils and rocks, can seep into some houses and increase the risk of lung cancer. Sources and paths of entry for indoor radon-222 gas. Figure 19-13

HEALTH EFFECTS OF AIR POLLUTION Normal human lungs (left) and the lungs of a person who died of emphysema (right). Figure 19-15

Air Pollution is a Big Killer • Each year, air pollution prematurely kills about 3 million people, mostly from indoor air pollution in developing countries. • In the U.S., the EPA estimates that annual deaths related to indoor and outdoor air pollution range from 150,000 to 350,000. • According to the EPA, each year more than 125,000 Americans get cancer from breathing diesel fumes.

Air Pollution is a Big Killer • Spatial distribution of premature deaths from air pollution in the United States. Figure 19-16

PREVENTING AND REDUCING AIR POLLUTION • The Clean Air Acts in the United States have greatly reduced outdoor air pollution from six major pollutants: • Carbon monoxide • Nitrogen oxides • Sulfur dioxides • Suspended particulate matter (less than PM-10)

Solutions: Reducing Outdoor Air Pollution • There are a of ways to prevent and control air pollution from coal-burning facilities. • Electrostatic precipitator: are used to attract negatively charged particles in a smokestack into a collector. • Wet scrubber: fine mists of water vapor trap particulates and convert them to a sludge that is collected and disposed of usually in a landfill.

Solutions: Reducing Outdoor Air Pollution • There are a # of ways to prevent and control air pollution from motor vehicles. • Because of the Clean Air Act, a new car today in the U.S. emits 75% less pollution than did pre-1970 cars. • There is an increase in motor vehicle use in developing countries and many have no pollution control devices and burn leaded gasoline.

Solutions Motor Vehicle Air Pollution Prevention Cleanup Mass transit Emission control devices Bicycles and walking Less polluting engines Less polluting fuels Car exhaust inspections twice a year Improve fuel efficiency Get older, polluting cars off the road Give buyers large tax write-offs or rebates for buying low-polluting, energy efficient vehicles Stricter emission standards Fig. 19-19, p. 460

Indoor Air Pollution • Little effort has been devoted to reducing indoor air pollution even though it poses a much greater threat to human health than outdoor air pollution. • Environmental and health scientists call for us to focus on preventing air pollution (especially indoor) in developing countries.

Solutions Indoor Air Pollution Cleanup or Dilution Prevention Use adjustable fresh air vents for work spaces Cover ceiling tiles & lining of AC ducts to prevent release of mineral fibers Increase intake of outside air Ban smoking or limit it to well ventilated areas Change air more frequently Set stricter formaldehyde emissions standards for carpet, furniture, and building materials Circulate a building’s air through rooftop green houses Prevent radon infiltration Use exhaust hoods for stoves and appliances burning natural gas Use office machines in well ventilated areas Use less polluting substitutes for harmful cleaning agents, paints, and other products Install efficient chimneys for wood-burning stoves Fig. 19-20, p. 461

Air Quality Index (AQI) • Measures levels of 5 criteria pollutants • Forecast of daily air pollution levels • Purpose to educate and protect public- focuses on health effects • Categories: green= good, yellow= moderate, orange= unhealthy for sensitive groups, red= unhealthy, purple= very unhealthy

Agriculture Fertilizers, animal wastes, etc. Water Pollution Municipal Waste • Sewage, fertilizers, dumping into drainage ditches, etc. Industrial Waste • Chemicals left over from manufacturing, waste products, etc.

Global Outlook: Stream Pollution in Developing Countries Water in many of central China's rivers are greenish black from uncontrolled pollution by thousands of factories. Figure 21-5

Case Study: India’s Ganges River: Religion, Poverty, and Health Religious beliefs, cultural traditions, poverty, and a large population interact to cause severe pollution of the Ganges River in India. Very little of the sewage is treated. Hindu believe in cremating the dead to free the soul and throwing the ashes in the holy Ganges. Some are too poor to afford the wood to fully cremate. Decomposing bodies promote disease and depletes DO.

Case Study: India’s Ganges River: Religion, Poverty, and Health Daily, more than 1 million Hindus in India bathe, drink from, or carry out religious ceremonies in the highly polluted Ganges River. Figure 21-6

POLLUTION OF FRESHWATER LAKES Dilution of pollutants in lakes is less effective than in most streams because most lake water is not mixed well and has little flow. Lakes and reservoirs are often stratified and undergo little mixing. Low flow makes them susceptible to runoff. Various human activities can overload lakes with plant nutrients, which decrease DO and kill some aquatic species.

Oil Spills When a tanker accident happens, it gets lots of publicity. But, more oil is released by normal operation of offshore wells, washing tankers & from pipeline or storage tank leaks. One estimate says that oil companies spill, leak, or waste per year an amount of oil equal to that shipped by 1000 huge Exxon Valdez tankers.

Floating Oil Oil coats the feathers of birds (especially diving birds) and the fur of marine animals, destroying the animals’ natural insulation and buoyancy Many drown or die of exposure from loss of body heat.

Reducing Water Pollution through Sewage Treatment Primary and Secondary sewage treatment. Figure 21-16

Safe Drinking Water Act It required the EPA to determine the maximum contaminant level, the max permissible amount of any pollutant that might adversely affect human health. Water Legislation

Water Quality Act • controlling toxic pollutant discharges • control non-point sources of pollution • authorized $18 billion for wastewater treatment • address problems such as coastal estuaries, the Great Lakes, and the Chesapeake Bay

Is Bottled Water the Answer? Some bottled water is not as pure as tap water and costs much more. 1.4 million metric tons of plastic bottles are thrown away. Fossil fuels are used to make plastic bottles. The oil used to produce plastic bottles in the U.S. each year would fuel 100,000 cars.

Love Canal — There Is No “Away” Between 1842-1953, Hooker Chemical sealed multiple chemical wastes into steel drums and dumped them into an old canal excavation (Love Canal). In 1953, the canal was filled and sold to Niagara Falls school board for $1. The company inserted a disclaimer denying liability for the wastes.

Core Case Study: Love Canal — There Is No “Away” In 1957, Hooker Chemical warned the school not to disturb the site because of the toxic waste. In 1959 an elementary school, playing fields and homes were built disrupting the clay cap covering the wastes. In 1976, residents complained of chemical smells and chemical burns from the site.

Core Case Study: Love Canal — There Is No “Away” President Jimmy Carter declared Love Canal a federal disaster area. The area was abandoned in 1980 (left). Figure 22-1

Core Case Study: Love Canal — There Is No “Away” It still is a controversy as to how much the chemicals at Love Canal injured or caused disease to the residents. Love Canal sparked creation of the Superfund law, which forced polluters to pay for cleaning up abandoned toxic waste dumps.

WASTING RESOURCES Solid waste: any unwanted or discarded material we produce that is not a liquid or gas. Municipal solid waste (MSW): produce directly from homes. Industrial solid waste: produced indirectly by industries that supply people with goods and services. Hazardous (toxic) waste: threatens human health or the environment because it is toxic, chemically active, corrosive or flammable.

WASTING RESOURCES Solid wastes polluting a river in Jakarta, Indonesia. The man in the boat is looking for items to salvage or sell. Figure 22-3

WASTING RESOURCES The United States produces about a third of the world’s solid waste and buries more than half of it in landfills. About 98.5% is industrial solid waste. The remaining 1.5% is MSW. About 55% of U.S. MSW is dumped into landfills, 30% is recycled or composted, and 15% is burned in incinerators.

Electronic Waste: A Growing Problem E-waste consists of toxic and hazardous waste such as PVC, lead, mercury, and cadmium. The U.S. produces almost half of the world's e-waste but only recycles about 10% of it. Figure 22-4

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