Answer to Question 1
ANSWER: A radiation (or surface) inversion typically forms during the night and early morning hours when the sky is clear and the winds are light. Radiation inversions also tend to be well developed during the long nights of winter. Radiation inversions normally last just a few hours, while subsidence inversions may persist for several days or longer. Subsidence inversions, therefore, are the ones commonly associated with major air pollution episodes. They form as the air above a deep anticyclone slowly sinks (subsides) and warms.
Answer to Question 2
ANSWER: Wind speed plays a role in diluting pollution. When vast quantities of pollutants are spewed into the air, the wind speed determines how quickly the pollutants mix with the surrounding air and, of course, how fast they move away from their source. Strong winds tend to lower the concentration of pollutants by spreading them apart as they move downstream. This process of spreading is called dispersion. Moreover, the stronger the wind, the more turbulent the air. Turbulent air produces swirling eddies that dilute the pollutants by mixing them with the cleaner surrounding air. Hence, when the wind dies down, pollutants are not readily dispersed, and they tend to become more concentrated.
Eversion and inversion of the foot.
Electromagnetic Radiation
Weather Typically Associated with a Warm Front (North America)
Signs and Symptoms of Radiation Exposure
Relationship of Sun Angle and Solar Radiation
The effects of a single crossover in a paracentric inversion heterozygote