APES CH. 17 Test
How does a primary pollutant differ from a secondary pollutant? Give an example of each.
A primary pollutant is emitted directly into the atmosphere and a secondary pollutant is produced from reactions within atmospheric substances. An example of a primary pollutant is carbon monoxide. An example of a secondary pollutant would be Tropospheric ozone.
Describe a thermal inversion. How do inversions contribute to severe smog episodes like the ones in London and in Donora, Pennsylvania?
A thermal inversion occurs when a layer of warm air settles over a layer of cooler air, and then traps the pollutants so they cannot spread throughout the atmosphere. Because of the elevated concentration of pollutants, atoms can react to form both industrial and photochemical smog very quickly.
How do chlorofluorocarbons (CFCs) deplete stratospheric ozone? Why is this depletion considered a long-term international problem? What was done to address this problem?
Chlorofluorocarbons decrease stratospheric ozone when they are hit with intense UV radiation from the from the sun that breaks the CFCs into chlorine and carbon atoms. In a two step chemical reaction, each newly freed chlorine atom can split an ozone molecule and then ready itself to split another one. During it's long residence time in the stratosphere, each free chlorine atom can catalyze the destruction of as many as 100,000 ozone molecules. This is considered a long term international problem because it is depleting over time and once the ozone layer protecting us is gone, humans and plants will both be vulnerable to the sun's harmful UV rays. The Montreal Protocol was created to address this problem.
What has happened with concentrations of criteria pollutants in US ambient air in recent decades? What has happened with our emissions of major pollutants? Name one health risk from toxic air pollutants.
Concentrations of criteria pollutants in US ambient air have decreased because of the Clean Air Acts and the Montreal Protocol. As well as general awareness of the surplus emissions, our emissions of major pollutants such as carbon dioxide are decreasing annually due to monitoring by the EPA. A health risk from toxic air pollutants is respiratory problems.
About how thick is Earth's atmosphere? Name one characteristic of each of the 4 atmospheric layers.
Earth atmosphere is about 300 miles thick, but most of it lies within 10 miles of the Earth. The troposphere is where all weather occurs. The stratosphere contains the ozone layer. The mesosphere is about 30 to 50 miles in altitude. The thermosphere is where photoionization occurs.
Name five common sources of indoor air pollution. For each, describe one way to reduce one's exposure to this source.
Heating equipment (stoves, etc.) can emit carbon monoxide. You can decrease exposure to CO by using said heating equipment less. New carpet and carpet materials can emit VOCs. You can reduce exposure to VOCs by installing tile and hardwood floors. Broken fluorescent lights emit mercury To decrease exposure you could use candles or regular bulbs. Certain paints can emit lead and VOCs. Use low VOC paints to reduce exposure.
How does photochemical smog differ from industrial smog? How does the weather influence smog formation?
Photochemical smog is produced from reactions with light while industrial smog is produced from factories burning coal. Weather can move smog with wind and topography can trap smog between mountains or valleys.
How does solar energy influence weather and climate? How do how do Hadley, Farrell and polar cells help to determine long-term climatic patterns location and the locations of biomes?
Solar energy plays a large part in Earth's temperature and amount of sunlight. Convection cells include Hadley cells, Farrell cells, and polar cells which help regulate temperature and barometric pressure so that biomes are able to flourish in their present locations.
Why are the effects of acid deposition often felt in areas far from where the primary pollutants are produced? List three impacts of acid deposition.
The effects of acid deposition are often felt in areas far from where the primary pollutants are produced because the smog, whether it is photochemical or industrial, can be blown thousands of miles away from where the process starts. Three effects of acid deposition are acidification of lakes and streams contributing to damage of high trees, accelerates decay of buildings and paint, and harms public health.
Where is the ozone layer located? How and why is stratospheric ozone beneficial for people, whereas tropospheric ozone is harmful?
The ozone layer is located in the stratosphere. Stratospheric ozone helps block UV rays. Tropospheric ozone acts as a pollutant and causes respiratory problems.
