SENSITIVITY OF LOCAL DEEP CONVECTION POTENTIAL OVER WATER BODIES TO SEA-SURFACE TEMPERATURE AND WIND-SPEED

The sea surface temperature (SST. wind speed, and surface-layer therma l stability affect surface thermal fluxes that are conducive to deep c onvection. In the present study, numerical model sensitivity evaluatio ns were carried out to quantify the impact of these properties on the potential for deep convection when short periods or airmass travel dis tances are pertinent. A comparison is also made between the widely use d Charnock formula for the sea surface roughness length and a more rec ent formulation. The numerical model results usually indicate enhancem ent of the deep convection potential as SST and wind speed increase fo r a given simulation period. However, for a given airmass travel dista nce, the total surface thermal fluxes and deep convection reduce moder ately with increased speed. Scaling evaluations are presented to provi de additional insight into the basic thermodynamic forcings.