The Role of Radiation in Tropical Cyclone Genesis and Early Intensification

University Of Colorado At Boulder, Boulder CO

Investigators

Abstract

Abstract This proposal seeks to transform our knowledge of the role of radiation in tropical cyclogenesis. Evidence suggests that radiation could play a crucial role in the early stages of genesis, particularly with the nighttime cooling and enhanced convection in the early morning hours. However, the complicated pathway to genesis under the influence of radiation and induced circulations is not well understood. Two genesis pathways have been identified in past work by the investigators in this study, and the role of radiation in these pathways will be examined in this research. Intellectual Merit This study will add to our understanding of tropical cyclogenesis by elucidating the role of radiation in the core of tropical cyclones and in the surrounding environment. The investigation will also explore other phenomena like the diurnal cycle of deep convection that appear to be connected to radiative forcing. While the vorticity field appears to be full of both positive and negative components near cold pool edges, overall vorticity increases with time. These are cutting-edge questions to explore now that we have the computational horsepower to simulate radiation and microphysics on cloud-resolving grids. Previous generations of models showed a diurnal cycle of convection (thunderstorms) but weren't able to simulate growth of the cirrus cloud canopy and the expanding cold rings aloft--features that are evident in nature. Progress under this proposal would build on previous work and improve our knowledge in this area of tropical meteorology. Broader Impacts This study will improve our understanding of the role of radiation in tropical cyclogenesis and could eventually lead to improved forecasting of these destructive storms. This research should help us understand how tropical cyclogenesis in future climates may differ from the present. Results will be disseminated to the community through conferences, workshops and published in peer-reviewed journals. A web site will be established to more broadly disseminate research results and provide open communications with the community.