Atmospheric Stability and Instability

Atmospheric stability : The resistance of the atmosphere to vertical motion.

Temperature distribution and lapse rates were discussed in Unit 4, where you learned that temperatures normally increase as we get closer to the earth's surface. This is due in part to the greater molecular activity of denser, more compressed air at lower altitudes. These conditions change throughout a 24-hour period, as the daytime solar heating and nighttime heat loss to and through the atmosphere tend to modify the temperature distributions.

Temperature inversion, is a reversal of the normal behavior of temperature in the troposphere, in which a layer of cool air at the surface is overlain by a layer of warmer air. (Under normal conditions, temperature usually decreases with height).