Abstract
The convective available potential energy (CAPE) based on monthly mean sounding has been shown to be relevant to deep convection in the tropics. The variation of CAPE with SST has been found to be similar to the variation of the frequency of deep convection at one station each in the tropical Atlantic and W. Pacific oceans. This suggests a strong link between the frequency of tropical convection and CAPE. It has been shown that CAPE so derived can be interpreted as the work potential of the atmosphere above the boundary layer with ascent in the convective region and subsidence in the surrounding cloud-free region.