The Annual Cycle of Moist Convection over West Africa

The annual cycle of the properties of moist convection over West Africa are examined using 15 years (1998-2012) of observations from the Tropical Rainfall Measuring Mission (TRMM) satellite. The properties of convective systems (e.g. system size and echo top height) are analyzed using precipitation features (PFs), contiguous areas of rain rate detected by the TRMM Precipitation Radar (PR). The frequency of different cloud types and their rainfall intensity are also examined. The annual cycle of convective properties is then related to variations in the convective environment (e.g. conditional instability, moisture, and shear) determined from reanalyses. Seasonal variations in the shape of latent heating profiles are also examined in both TRMM heating products and reanalyses. Latent heating profiles are compared to variations in the relative frequency of different cloud types and their vertical structure determined from the TRMM PR. Variations in the shape of latent heating profiles between the phases of the West African monsoon are then related to the structure of the monsoon circulation.