Frequently occurs on clear nights Radiative cooling occurs at Earths surface

Frequently occurs on clear nights radiative cooling

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Frequently occurs on clear nights. Radiative cooling occurs at Earth’s surface, resulting in the ground and air next to the Earth’s surface cooling more rapidly than the air aloft. Temperature inversions trap pollutants in a narrow zone near Earth’s surface.
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Stable Air Can produce clouds even though it resists upward movement . Processes (lifting mechanisms) do exist which force stable air aloft. When stable air is forced aloft, the clouds produced are widespread and have very little vertical thickness compared with their horizontal dimension. Precipitation is light to moderate . On a dreary, overcast day with light drizzle, stable air was forced aloft. Widespread fog is another sign of stability .
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Absolute Instability Occurs when the environmental lapse rate is greater then the dry adiabatic rate. When absolute instability conditions exist, the ascending parcel of air is always warmer than its environment and will continue to rise because of its own buoyancy . Absolute instability occurs most often during the warmest months and on clear days when solar heating is intense . When the lowermost layer of the atmosphere is heated to a much higher temperature than the air aloft, the result is a very steep environmental lapse rate and a very unstable atmosphere . This type of instability, caused by strong surface heating, is generally confined to the first few miles (kilometers) of the atmosphere. .
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Above a few miles (kilometers), the environmental lapse rate assumes a more “normal” value. This results in the temperature dropping slowly with altitude, creating a more stable temperature regime . Clouds produced only by surface heating lack great vertical height, and thus rarely produce violent weather. These clouds may produce short, heavy rains, but are usually widely scattered. These rains and clouds are
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  • Fall '16
  • Mark Smith
  • Heat, Atmospheric thermodynamics, Instability, 100m, 1000 feet

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