7A.5 Evaluation of wet scavenging for the May 29, 2012 DC3 severe storm

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Bela, Megan, University of Colorado (CU), Barth, Mary, National Center for Atmospheric Research (NCAR), John Wong, Owen Toon, CU, Hugh Morrison, Morris Weisman, Kevin Manning, Glen Romine, Wei Wang, NCAR, Kristen Cummings, University of Maryland, Kenneth Pickering, National Aeronautics and Space Administration, and the DC3 Science Team

Deep convective thunderstorms affect the vertical distribution of chemical species through vertical transport, lightning-production of NOx, wet scavenging of soluble species as well as aqueous and ice chemistry. This work focuses on the May 29 Oklahoma thunderstorm from the DC3 (Deep Convective Clouds and Chemistry) field campaign. WRF-Chem simulations at cloud parameterizing (dx=15km) and cloud resolving scales (dx=3 and 1km) are being conducted to investigate wet scavenging of soluble trace gases. The simulated meteorology, evaluated with the NEXRAD radar reflectivity, is shown to represent the structure and evolution of the storm, although the simulated storm triggers about an hour early, has a larger area of high reflectivity and extends further north than observed in NEXRAD. Vertical distributions of trace gases with varying solubilities within the storm and immediately surrounding the storm are compared with observations from the GV and DC-8 aircraft in storm inflow and outflow regions. Observed mean vertical profiles of some soluble species in outflow are better represented in the model with scavenging, while others are overly scavenged. The dx=15km simulation is further evaluated for its prediction of lightning flash rate, which is based on the convective parameterization and poorly matches the flash rate observations. We will provide recommendations on improving the flash rate parameterization.