Observed Links between Deep Convection Aggregation and Tropical Cloud Variations
Spatial organization of convection is found to play an important role in modulating tropical radiation budget by altering the distribution of moisture and structural characteristics and radiative properties of tropical clouds. It is still unclear how large-scale convective aggregation interacts with the distribution of moisture, clouds and the related atmospheric cloud radiative effects, and large-scale circulation, and how it potentially affects cloud feedbacks to surface warming. Here, we investigate these relationships with multiple independent satellite and reanalysis datasets and disentangle the effect of deep convective aggregation on the observed variations of subtropical low clouds from several local clouds controlling factors including sea surface temperature, lower tropospheric stability, free tropospheric and boundary layer mixing, and subsidence rate. In this presentation, I will discuss how deep convective aggregation may impact low cloud feedback through several physical pathways. Results from climate model simulations in terms of these relationships will also be presented and discussed.