Seminar: Assessing the cause for the catastrophic flooding during Hurricane Harvey

Abstract:

Hurricane Harvey produced catastrophic flooding (about 555 mm) in southeast Texas during 25-27 August 2017. The genesis and development of tropical cyclones are regulated by dynamic, thermodynamic, and microphysical processes, including sea surface temperature (SST), vertical wind shear, vorticity, and humidity of the free troposphere. Although several recent studies have linked Hurricane Harvey’s devastation to climate change or changes in land use due to urbanization, the cause of the catastrophic flooding remains uncertain. In particular, tropical cyclones are driven by latent heat release from water condensation and are inevitably linked to the abundance of aerosols by acting as cloud condensation nuclei. In this talk, I will present results from both measurements and numerical model simulations to investigate the impacts of anthropogenic aerosols on deep moist convection, precipitation, and lightning activities during hurricane Harvey. Our work shows a non-negligible effect of anthropogenic aerosols during this regional extreme weather event, highlighting the necessity of accounting for the aerosol effects in hurricane forecast models to accurately predict precipitation and to minimize the storm damage along the heavily industrialized Gulf of Mexico region.