Dual Doppler Radar Investigation of the Tropical Convective Boundary Layer

Abstract

Radar observations of the convective boundary layer wore made during the ?COPT81? experiment in May?June 1981 over western Africa. The lower atmosphere was characterized by the interaction between the southerly monsoon and the African easterly jet above it. The mean wind shear between both Bows is found to organize convective elements along preferred directions and to transfer energy to the perturbed field (velocity variances, momentum fluxes). However, the convective organization is also the cause of increasing horizontal variance and in some cases of a negative shear stress production. The global behavior of the convective boundary layer in the four observed situations appeared similar to those observed in middle latitudes, but the strong wind shear is an important feature of the layer.