The Stratiform Radiation Effect on Tropical Organized Deep Convection

Self-aggregation studies have implicated the importance of longwave (LW) cloud-radiative forcing (CRF) in facilitating or accelerating the upscale development of tropical moist convection. While different cloud types are known to have distinct CRF, their distinct roles in driving upscale development through radiative feedback is largely unexplored. Considering the impact CRF has on convection, we hypothesize that different cloud modes have different effects on mesoscale tropical convection through radiative feedback, with stratiform regions dominating contributions toward organizing convection. We test this hypothesis by analyzing output from convection-permitting ensemble Weather Research and Forecasting (WRF) model simulations of Super Typhoon Haiyan. Using a novel column-by-column cloud classification scheme introduced herein, we use this model output to identify the relative contribution of five cloud types (shallow, congestus, and deep convection; and stratiform and anvil clouds) to the direct LW radiative forcing and the upscale development of convection via the LW moist static energy variance term. Results indicate that stratiform and anvil regions contribute dominantly to the domain averages of these variables.