Relationship Between Convection and African Easterly Waves

The interaction between different deep convection types and African easterly waves (AEWs) phases and their impact on tropical cyclogenesis (TC-genesis) over Tropical North Africa is studied using 1.25° grid MERRA data at 3-hourly time step and weather state (WS) dataset from the International Cloud Climatology Project (ISCCP). We also use 3-hourly, global 0.5° horizontal grid cloud-top brightness temperature to study deep convection. Our results show isolated, less organized type of deep convection transitioning to a larger scale well organized type of deep convection near East and West African Mountain ranges. In this work, we investigate the mechanisms that determine this transition. Specifically, the role background environment, specifically to the wind shear in East Africa and diurnal cycle will be explored. Using ISCCP data we will identify regions of cold cloud tops (T < 245 K) and convective towers (T < 220 K) and match these with different types of WS. This analysis will also give additional information about the time variation of cold clouds, for example, their motion, size variation, and lifetime. We will also study year association of convection and AEWs and how they vary across higher elevations across Tropical North Africa and to see is there is any implication for TC-genesis. Understanding AEWs variability and their relationship to deep convection (related to convective rainfall) is important because their variability can have an important impact in Africa and over the Atlantic TCs.