Author Question: Discuss the role of topography in air pollution. What will be the ideal ... (Read 156 times)

Charlie

  • Hero Member
  • *****
  • Posts: 640
Discuss the role of topography in air pollution.
  What will be the ideal response?

Question 2

Describe how the semipermanent Pacific high off the coast of California contributes to air pollution in that region.
  What will be the ideal response?



nyrave

  • Sr. Member
  • ****
  • Posts: 344
Answer to Question 1

ANSWER: The shape of the landscape (topography) plays an important part in trapping pollutants. At night, cold air tends to drain downhill, where it settles into low-lying basins and valleys. The cold air can have several effects: It can strengthen a pre-existing surface inversion, and it can carry pollutants downhill from the surrounding hillsides. Valleys prone to pollution are those completely encased by mountains and hills. The surrounding mountains tend to block the prevailing wind. With light winds, and a shallow mixing layer, the poorly ventilated cold valley air can only slosh back and forth like a murky bowl of soup. Valleys susceptible to stagnant air exist in just about all mountainous regions. Air pollution concentrations in these valleys tend to be greatest during the colder months. During the warmer months, daytime heating can warm the sides of the valley to the point that upslope valley winds vent the pollutants upward, like a chimney.

Answer to Question 2

ANSWER: The position of the semipermanent Pacific high off the coast of California contributes greatly to the air pollution in that region. The Pacific high promotes subsiding air, which warms the air aloft. Surface winds around the high promote upwelling of ocean water. Upwellingthe rising of cold water from belowmakes the surface water cool, which, in turn, cools the air above. Warm air aloft coupled with cool, surface (marine) air together produce a strong and persistent subsidence inversionone that exists 80 to 90 percent of the time over the city of Los Angeles between June and October, the smoggy months. The pollutants trapped within the cool marine air are occasionally swept eastward by a sea breeze. This action carries smog from the coastal regions into the interior valleys producing a smog front.



Related Topics

Need homework help now?

Ask unlimited questions for free

Ask a Question
 

Did you know?

According to the American College of Allergy, Asthma & Immunology, more than 50 million Americans have some kind of food allergy. Food allergies affect between 4 and 6% of children, and 4% of adults, according to the CDC. The most common food allergies include shellfish, peanuts, walnuts, fish, eggs, milk, and soy.

Did you know?

IgA antibodies protect body surfaces exposed to outside foreign substances. IgG antibodies are found in all body fluids. IgM antibodies are the first type of antibody made in response to an infection. IgE antibody levels are often high in people with allergies. IgD antibodies are found in tissues lining the abdomen and chest.

Did you know?

Every 10 seconds, a person in the United States goes to the emergency room complaining of head pain. About 1.2 million visits are for acute migraine attacks.

Did you know?

Blood is approximately twice as thick as water because of the cells and other components found in it.

Did you know?

Every flu season is different, and even healthy people can get extremely sick from the flu, as well as spread it to others. The flu season can begin as early as October and last as late as May. Every person over six months of age should get an annual flu vaccine. The vaccine cannot cause you to get influenza, but in some seasons, may not be completely able to prevent you from acquiring influenza due to changes in causative viruses. The viruses in the flu shot are killed—there is no way they can give you the flu. Minor side effects include soreness, redness, or swelling where the shot was given. It is possible to develop a slight fever, and body aches, but these are simply signs that the body is responding to the vaccine and making itself ready to fight off the influenza virus should you come in contact with it.

For a complete list of videos, visit our video library