On Destabilization of Clouds by Radiative Cooling

Abstract

Destabilization of clouds due to long-wave radiation is computed as the difference in the radiative cooling rates across the cloud layer. The changes in destabilization and cooling rates due to changes in cloud amount, cloud altitude, cloud thickness, and temperature structure of the lower layer have been assessed separately. Changes in cloud amount cause large changes in the destabilization value and cooling rates near the top and base of the cloud. For a given cloud layer, destabilization is less in low clouds than in middle or high clouds. The presence of an inversion is equivalent to that of a cloud layer and is associated with weak destabilization.