Modeling and Analysis of Aerosol-Cloud Interactions in a Severe Convection Case with an Elevated Smoke Plume (Invited Presentation)

The severe storms occurring in northeast Colorado and southwest Nebraska on 22 June 2012 during the Deep Convective Clouds and Chemistry (DC3) field campaign were unique in that one severe storm ingested a wildfire smoke plume at ~7 km altitude while other storms in the area did not. This case provides the opportunity to explore via cloud-scale modeling the effect of the smoke aerosols on the storm properties, such as cloud drop and ice number concentrations, precipitation, and lightning flash rate. We use the Weather Research and Forecasting model coupled with chemistry (WRF-Chem) and CSU RAMS model to examine these aerosol-cloud interactions.  Initial results find increased cloud drop and ice number concentrations when smoke aerosols are included, but little to no change in precipitation at the surface. These results will be discussed in terms of processes occurring along trajectories in the storm that were launched in the modeled smoke plume and storm inflow regions. In addition, the effect of aerosol-cloud interactions on precipitation changes will be examined in the context of precipitation changes caused by using different boundary layer or cloud physics model parameterizations.