Page 497 - Environment: The Science Behind the Stories

mystery, and when symptoms are general and nonspecific, the mold, and carbon monoxide. Because carbon monoxide is so
illness is often called sick-building syndrome. The U.S. Occu- deadly and so hard to detect, many homes are equipped with
pational Safety and Health Administration (OSHA) estimates detectors that sound an alarm if incomplete combustion pro-
that 30–70 million Americans have suffered ailments related to duces dangerous levels of CO. In addition, keeping rooms and
the building in which they live. We can reduce the prevalence air ducts clean and free of mildew and other biological pol-
of sick-building syndrome by using low-toxicity construction lutants will reduce potential irritants and allergens. Most of
materials and ensuring that buildings are well ventilated. all, keeping our indoor spaces well ventilated will minimize
concentrations of the pollutants among which we live.
Progress is being made worldwide in alleviating the
WeigHiNg tHe iSSUeS health toll of indoor air pollution. Researchers calculate that
HOW SAFe iS yOUr iNdOOr eNVirONMeNt? Think about rates of premature death from indoor air pollution dropped
the amount of time you spend indoors. Name some potential nearly 40 percent from 1990 to 2010. Taking steps like those
indoor air quality hazards in your home, work, or school envi- described here should bring us further progress in safeguard-
ronment. Are these spaces well ventilated? What could you do ing people’s health.
to improve the safety of the indoor spaces you use?
Conclusion
We can enhance indoor air quality
Indoor air pollution poses potentially serious health hazards,
Using low-toxicity materials, monitoring air quality, keeping but by keeping informed and taking appropriate precautions
rooms clean, and providing adequate ventilation are the keys on a personal basis, we each can minimize our risks. Outdoor
to alleviating indoor air pollution in most situations. Remedies air pollution has been addressed more effectively by gov-
for fuelwood pollution in the developing world include drying ernment legislation and regulation, together with pollution-
wood before burning (which reduces the amount of smoke pro- control technologies. Indeed, reductions in outdoor air
duced), cooking outside, shifting to less-polluting fuels (such pollution in the United States and other industrialized nations
as natural gas), and replacing inefficient fires with cleaner represent some of the greatest strides made in environmen-
stoves that burn fuel more efficiently. The Chinese govern- tal protection to date. The global depletion of stratospheric
ment invested in a program that has placed fuel-efficient ozone has been halted thanks to our efforts, and acid depo-
stoves in millions of homes across China. Installing hoods, sition is gradually being addressed. Room for improvement
chimneys, or cooking windows can increase ventilation for remains, however, particularly in reducing acid deposition
little cost, alleviating most indoor smoke pollution. and photochemical smog. In the developing world, indoor
In the industrialized world, we can try to avoid cigarette and outdoor air pollutant levels are higher and take a heavy
smoke, limit our use of plastics and treated wood, and restrict toll on people’s health. Reducing pollution from indoor
our exposure to pesticides, cleaning fluids, and other toxic fuelwood burning, automobile exhaust, coal combustion in
substances by keeping them in garages or outdoor sheds. The outmoded facilities, and other sources will continue to pose
EPA recommends that we test our homes and offices for radon, challenges as the world’s less-wealthy nations industrialize.

reviewing Objectives

you should now be able to: Relate weather and climate to atmospheric conditions
• The sun’s energy heats the atmosphere, drives air circula-
Describe the composition, structure, and function of tion, and helps determine weather, climate, and the sea-
Earth’s atmosphere sons. (pp. 470–471)
• The atmosphere moderates climate, provides us oxygen, • Weather is a short-term phenomenon, whereas climate
conducts and absorbs solar radiation, and transports and is a long-term phenomenon. Fronts, pressure systems,
recycles nutrients and waste. (p. 468) and the interactions among air masses influence weather.
• The atmosphere consists of 78% nitrogen gas, 21% oxygen (pp. 471–472)
gas, and a variety of other gases in minute concentrations. • Global convective cells called Hadley, Ferrel, and polar
(p. 468) cells create latitudinal climate zones. (p. 473)

• The atmosphere includes four layers: the troposphere, • Hurricanes and tornadoes are types of cyclonic storms that
stratosphere, mesosphere, and thermosphere. Temperature can threaten life and property. (p. 474)
and other characteristics vary across these layers. Ozone is
496 concentrated in the stratosphere. (pp. 468–469)

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