Page 499 - Environment: The Science Behind the Stories

4. List the main sources responsible for the emission of the 8. Explain how chlorofluorocarbons (CFCs) deplete strato-
following pollutants—CO, SO , NO , VOCs, and particu- spheric ozone. Why is this depletion considered a long-
x
2
late matter into the atmosphere. term international problem? What was done to address
5. How does a primary pollutant differ from a secondary this problem?
pollutant? Give an example of each. 9. Why are the effects of acid deposition often felt in areas
6. Using the examples of Tehran and Los Angeles, discuss far from where the primary pollutants are produced? List
the special problems that vehicles create for urban out- three impacts of acid deposition.
door air pollution. 10. Why is indoor pollution still such a huge problem? What
7. How does photochemical smog differ from industrial are the most dangerous indoor pollutants in developing
smog? How do the weather and topography influence and developed nations?
smog formation?

Seeking Solutions

1. Consider responses to the photochemical smog pollution dioxide. Your county is partly rural but is home to a city of
that has plagued Los Angeles, Mexico City, and other 200,000 people and 10 sprawling suburbs. There are sev-
metropolitan areas. Describe several ways in which major eral large and aging coal-fired power plants, a number of
cities have tried to improve their air quality. factories with advanced pollution control technology, and
2. Name one type of natural air pollution, and discuss how no public transportation system. What steps would you
human activity can sometimes worsen it. What potential urge the county government to take to meet the air quality
solutions can you think of to minimize this human impact? standards? Explain how you would prioritize these steps.
3. Describe how and why emissions of major pollutants 6. Think iT Through You have been elected mayor of
have been reduced by well over 50% in the United States the largest city in your state. Your city’s residents are com-
since 1970, despite increases in population, energy use, plaining about photochemical smog and traffic congestion.
and economic activity. Traffic engineers and city planners project that population
and traffic will grow by 20% in the next decade. Some
4. International action through a treaty has helped to halt fur- experts are urging you to restrict traffic into the city, allow-
ther stratospheric ozone depletion, but other transboundary ing only cars with odd-numbered license plates on odd-
pollution issues, including acid deposition, have not yet been numbered days, and those with even-numbered plates
addressed as effectively. What types of actions do you feel on even-numbered days. However, business owners fear
are appropriate for pollutants that cross political boundaries?
losing money should these measures discourage shoppers
5. Think iT Through You have become the head of your from visiting. Consider the particulars of your city, and
county health department, and the EPA informs you that then decide whether you will pursue an odd-day/even-day
your county has failed to meet the national ambient air driving program, and explain why or why not. What other
quality standards for ozone, sulfur dioxide, and nitrogen steps would you take to address your city’s smog problem?

Calculating Ecological Footprints

“While only some motorists contribute to traffic fatalities, Total NO NO emissions
X
X
all motorists contribute to air pollution fatalities.” So stated a emissions (lb) from vehicles (lb)
writer for the Earth Policy Institute, pointing out that air pol- You
lution kills far more people than vehicle accidents. According
to EPA data, emissions of nitrogen oxides in the United States Your
class
in 2012 totaled 11.3 million tons. Nitrogen oxides come from
fuel combustion in motor vehicles, power plants, and other Your
industrial, commercial, and residential sources, but fully 6.4 state
million tons of the 2012 total came from vehicles. The U.S. United 22.6 billion 12.8 billion
Census Bureau estimates the nation’s population to have been States
313.9 million in 2012 and projects that it will reach 346.7 mil- Data from U.S. EPA.
lion in 2025. Considering these data, calculate the missing
498 values in the table below (1 ton = 2000 lb).

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