REVIEW: Lesson Summary

Summary

Air pollution gets trapped by an inversion layer. Salt Lake City, UT. 

• The atmosphere is made of gases that are essential for photosynthesis and respiration, among other life activities
• The atmosphere is made of primarily nitrogen and oxygen. The atmosphere also contains minor amounts of other gases, such as carbon dioxide and water vapor
• The layers of the atmosphere are the troposphere, stratosphere, mesosphere, thermosphere and exosphere
• Not everything in the atmosphere is a gas: particulates are particles that are important as the nucleus of raindrops and snowflakes. Too much particulate matter is a form of air pollution
• Air density and pressure decrease with increasing altitude
• Gravity mpulls more air molecules toward the center of the planet
• Warm air rises, cool air sinks. Warm air has lower density
• Different layers of the atmosphere have different temperature gradients
• Temperature gradient is the change in temperature with distance
• Air pollution is any substance released into the atmosphere in harmful or unnatural amounts
• Types of air pollution include particulate matter, acid rain, tropospheric ozone (photochemical smog) and CFCs

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