Downdrafts in the near cloud environment of deep convective updrafts

Abstract

Abstract We used a large domain, large eddy simulation (LES) of tropical deep convection to investigate the properties of 3‐D cloudy updrafts and the near cloud environment (NCE) directly adjacent to them. We show for the first time that the properties of the air in the NCE of deep convection imply the existence of a subsiding shell like that which is already known to exist around shallow convection. We show that there is negative buoyancy in the NCE due to mixing and evaporative cooling, and that there is significant negative net mass flux in the NCE relative to the cloudy updraft mass flux. This demonstrates that the “subsiding shell” viewpoint of the NCE region of shallow cumulus updrafts can and should be applied to deep convective updrafts as well.