Chapter 18
What is air pollution?
1. presence of chemicals in atmosphere in concentrations high enough to harm: - organisms, ecosystems, or human-made materials, or alter climate
what are the effects of lead on the human body?
The neurotoxin can impact children bc they are most vulnerable, and can cause death brain damage, and paralysis
What percentage of these deaths are caused by indoor air pollution? Describe the health threat from diesel fumes.
- 3% worldwide - cancer from breathing soot-laden diesel fumes emitted by buses and trucks
What are four ways to reduce indoor air pollution?
- Test for radon and formaldehyde inside your home and take corrective measures as needed - Do not buy furniture and other products containing formaldehyde - Test your home or workplace for asbestos fiber levels and check for any crumbling asbestos materials
List the advantages and disadvantages of using an emissions trading program.
- advantages: cheaper and more efficient than gov. regulation - without strict government oversight -> cheating possible, b/c cap-and-trade based largely on self-reporting of emissions
Approximately, how many people die prematurely from air pollution each year in the world and in the United States?
1. 3.2 million people worldwide die prematurely each year—an average of nearly 365 deaths every hour—from the effects of outdoor air pollution. 2. 150,000 to 350,000 people US
how do SABC contribute to acid rain
1. Aerosols in the clouds are pulled into thunder-storms -> 2. dump acid rain into the Indian and Pacific Oceans 3. harming marine life and ecosystems
Industrial (Grey-air) smog:
1. Caused: emissions from motor vehicles, industrial facilities, and power plants 2. A mix of sulfur dioxide, suspended droplets of sulfuric acid, and a variety of suspended solid particles (ammonium sulfate) in outside air. 3. Primarily as a result of burning coal (which results in sulfur dioxide, carbon monoxide, carbon dioxide, and soot)
What are the top three indoor air pollutants in the United States? Three reasons why they present a serious threat to human health.
1. Chloroform Source: Chlorine-treated water in hot showers Possible threat: Cancer 2.Radon-222 Source: Radioactive soil and rock surrounding foundation, water supply Threat: Lung cancer 3.Nitrogen oxides Source: Unvented gas stoves and kerosene heaters, woodstoves Threat: Irritated lungs, children's colds, headaches
Summarize the major ways to reduce emissions from power plants and motor vehicles.
1. Disperse emissions (which increase downwind pollution) using tall smokestacks 2. Remove pollutants from smokestack gases 3. Tax each unit of pollution produced
Explain how these laws can be strengthened, according to some scientists.
1. Greater emphasis on prevention air pollution 2. Sharply reduce emissions from older call burning power and industrial plants, cement plants, oil refineries, and waste incinerators 3. Continue to improve fuel efficiency standards for motor vehicles 4. Regulate more strictly the emissions from motorcycles and two-cycle gasoline engines used in devices such as chainsaws
How do SABC affect food production and solar power
1. Hindering photosynthesis & Collins land and ocean surfaces -> reducing evaporation and rainfall 2. Dimming of sunlight -> lowers output of centralized solar energy power plants
What are its major environmental impacts on vegetation, lakes, human-built structures, and human health?
1. Low pH reduces plant productivity and the ability of soils to buffer or neutralize acidic inputs - weaken trees, vulnerable to stresses (severe cold, diseases, insect attacks, and droughts) - mountaintop forests = terrestrial areas hit hardest by acid deposition a) tend to have thin soils w/out much buffering capacity and areas are bathed almost continuously in highly acidic fog and clouds b) result: uncontrolled emissions of sulfur dioxide and other pollutants can devastate the vegetation in these sensitive areas
What are the major differences between troposphere and stratosphere?
1. layer closest to earth; Air movements: troposphere -> Earth's weather and climate 2. 2nd layer; less matter than troposphere; composition: volume of water vapor is 1/1,000th than tropo. & concentration of ozone: higher
3 big ideas
1. Outdoor air pollution, in the forms of industrial smog, photochemical smog, acid deposition, and indoor air pollution, is a serious global problem. 2. Each year, at least 2.4 million people die prematurely from the effects of air pollution; indoor air pollution, primarily in less-developed countries, causes about two-thirds of these deaths. 3. We need to put our primary emphasis on preventing outdoor and indoor air pollution throughout the world.
define ozone layer
1. Ozone layer: concentrated in portion of stratosphere - 17-26 kilometers (11-16 miles) above sea level - produced when some oxygen molecules in layer interact w/ ultraviolet radiation emitted by sun (30_2 + UV -><- 2O_3) - global sunscreen
what is the difference between primary and secondary air pollutants and give an example of each.
1. Primary pollutants: chemicals or substances emitted directly into the air from natural processes and human activities at concentrations high enough to cause harm (CO, NO, CO_2) 2. Secondary pollutants: in the atmosphere, some primary pollutants react with one another and with other natural components of air to form new harmful chemicals (SO_3, HNO_3, O_3)
Explain why radon-222 is an indoor air pollution threat, how and where it occurs, and what can be done about it.
1. Radon-222 Source: Radioactive soil and rock surrounding foundation, water supply Threat: Lung cancer 2. Human health risks kills 21,000 people/year in the U.S. Decays into Polonium-210 a) Can expose the lungs to high amounts of radiation b) 90% of radon-related lung cancers occur among current or former smokers what can be done: radon test
Describe the human body's defenses against air pollution, how they can be overwhelmed, and the illnesses that can result.
1. Respiratory System: protects: - hairs in nose filter large particles - sticky music in lining of upper respiratory tract captures smaller particles and dissolves some gaseous pollutants - sneezing & coughing: expel contaminated air and mucus when irritate respiratory system 2. Cilia 3. Can be overwhelmed with prolonged/acute exposure to air pollutants 4. Fine and ultrafine particulates can get lodged deep in lungs and contribute to: lung cancer, asthma, heart attack, and stroke
Impact south asian brown clouds have on photosynthesis
1. Soot & sulfate particles in South Asian Brown Clouds decrease amount of sunlight that penetrates the atmosphere 2. dimming can lead to lower food production by hindering photosynthesis 3. cooling land and ocean surfaces, and reducing evaporation and rain-fall.
How could the South Asian Brown Clouds be a factor in the melting on the Himalayan glaciers?
1. Soot and some particles in brown clouds absorb sunlight and heat the air above the glaciers 2. Black soot falling on the white surface of the glaciers also decreases their ability to reflect sunlight back into space 3. glaciers then absorb more solar energy, which adds to the warming of the air above them and also increases the rate of glacial melting
Define stratosphere
1. Stratosphere: next layer above the earth's surface; lower portion holds enough ozone (O3) gas to filter out about 95% of the sun's harmful ultraviolet (UV) radiation - global sunscreen allows life to exist on surface of planet - reaching from 17 to 50 kilometers (11-31 miles)
What is acid deposition and how does it form?
1. Sulfuric acid and nitric acid compounds 2. Wet deposition - rain, snow, fog, cloud vapor 3. Dry deposition - particles a) Substances remain in the atmosphere 2-14 days b) Caused mainly by coal-burning power plants and motor vehicle emissions c) Threatens human health, aquatic life and ecosystems, forests, and human-built structures in some regions
Photochemical (brown-air) smog:
1. Sunlight (UV radiation) plus cars (primary pollutants) 2. VOCs + NOx + Heat + Sunlight yields: Ground level O3 (ozone) and other photochemical oxidants (NO2 and PANs), Aldehydes, Other secondary pollutants, and Brown-air smog
Summarize the U.S. air pollution laws and how they have worked to reduce pollution. (Clean Air Acts of 1970, 1977, 1990)
1. The Federal Government directed the Environmental Protection Agency to establish air-quality standards for 6 outdoor air pollutants: 2. Carbon monoxide (CO), nitrogen dioxide (NO2), sulfur dioxide (SO2), suspended particulate matter (spm), ozone (O3), and lead (Pb) 3. Primary goal: human health 4. Secondary goal: environmental/property 5. strength air pollution laws
Define troposphere
1. Troposphere: inner layer of the atmosphere; contains air we breathe, consisting mostly of nitrogen (78% of the total volume) and oxygen (21%) - remaining 1% of air = water vapor, carbon dioxide, and methane - extends 17 kilometers (11 miles) above sea level at the tropics and about 7 kilometers (4 miles) above earth's north and south poles
Explain the connections among low-sulfur coal, atmospheric warming, and toxic mercury.
1. U.S power plants - lowered SO2 emissions by switching high to low sulfur coals 2. has increased CO2 emissions that contribute to atmospheric warming & climate change 3. low sulfur coal: high levels of toxic mercury and other trace metals emitted into atmosphere
List three major ways to reduce acid deposition.
1. Use of affordable and cleaner-burning natural gas and wind 2. large amounts of limestone or ground lime are used to neutralize some acidified lakes and surrounding soils 3. Air pollution laws
What is a temperature inversion? How does it affect air pollution levels?
1. When a layer of warm air can temporarily lie atop the cooler air near the ground. 2. Cool air is more dense -> does not rise 3. Pollutants can build up in the cool air to harmful or even lethal concentrations
List five harmful effects of such depletion
1. Worse sunburns. 2. increased acid deposition 3. immune system suppression 4. reduce yield for some crops 5. CFCs: greenhouse gasses
5 natural factors that increase air pollution
1. gravity 2. rain and snow 3. salty sea spray 4. winds 5. chemical reactions: (e.g., SO2 + O2 -> SO3 + H2O -> H2SO4)
What has the world done to reduce the threat of ozone depletion in the stratosphere?
1. substitutes for CFCs 2. U.S. government asked the UN to enact mandatory reductions in HFC emissions through the Montreal Protocol.
6 factors that decrease air pollution
1. urban buildings 2. hills and mountains 3. high temperatures (increase chem. reactions that lead to dev. of photochemical smog) 4. emissions of VOCs from trees and plants increase formation of photochemical smog 5. 5. grasshopper effect (spread of pollutants at high altitudes to polar areas) 6. temperature inversion
How might projected climate change undermine this progress?
As atmosphere warms and the global climate changes, ozone levels may take much longer to return to where they were before ozone thinning began (or may never recover completely)
How can pollutants be detected biologically?
Biologically: are/were living organisms; Animal Dander (minute scales from hair, feathers, or skin), dust mite and Cockroach parts, infectious agents (bacteria or viruses), and Pollen
How have human activities depleted ozone in the stratosphere?
CFCs: coolants in air conditioners and refrigerators, propellants in aerosol spray cans, cleaners for electronic parts (computer chips), fumigants for granaries and ships' cargo holds, and gases used to make foam insulation and packaging
list of major outdoor air pollutants
Carbon monoxide, carbon dioxide, Nitrogen oxides [Nitric oxide (NO); Nitrogen dioxide (NO2), Nitrous oxide (N2O)], Sulfure oxides [Sulfur dioxide (SO2), Sulfur trioxide (SO3)], Particulates [Suspended particulate matter (SPM)], Ozone (O3) [Ingredient of photochemical smog], Volatile organic compounds (VOCs) [Hydrocarbons from plants Methane]
How can pollutants be detected chemically?
Chemically: enters human body through: - human inhalation, ingestion, or dermal absorption - Effects: damage to liver, kidneys, nervous systems, bool and immune system
Why is preventing air pollution more important than controlling it?
If we stop it from growing, control won't be as necessary
how long does it take for SABC's pollutants to circle the globe
It takes 3-4 days for pollutants to circle the globe
Where is "bad" ozone
Ozone in the troposphere near ground level: "bad" ozone; ground level ozone
Where do the substances come from (SABC)
These substances come from from drought and from the clearing and burning of forests for planting crops, and human sources, including coal-burning power and industrial plants, motor vehicles, and road construction.
What makes south asian brown clouds
They are made of small particles of dust, smoke, and mercury.
Where is "good" ozone? What does good ozone do? How is ozone made?
Where: Stratosphere What: protects from harmful UV radiation How: heat and sunlight cause chemical reactions between oxides of nitrogen (NOX ) and Volatile Organic Compounds (VOC) -> Hydrocarbons
How does density, as it relates to atmospheric pressure, differ in each layer?
decreases with altitude b/c fewer gas molecules at higher altitudes
What is the major indoor air pollutant in many less-developed countries?
indoor burning of wood, charcoal, dung, crop residues, coal, and other fuels in open fires or in unvented or poorly vented stoves