High Resolution Tracing of Wildfire Smoke

Abstract:

While studies suggest an increasing trend in number and size of wildfire incidents, concerns are also rising about the losses sustained at different levels. When an incident occurs, especially in Wildland-Urban Interfaces (WUIs), direct consequences at that region include fatalities, infrastructure and property destruction, and people relocation. However, secondary products (i.e., smoke) go beyond the extent of the incidents, sometimes miles away, and impose activity restrictions and health issues when they reach a community. In this study an advanced physics-based model that captures the 3-D interaction between atmosphere, fuel at the surface, and the fire (WRF-SFIRE) is applied. The raster outputs representing the fire spread over time are used as the dynamic emission sources and the smoke is traced using the Stochastic Time-Inverted Lagrangian Transport (STILT) model that is driven by the high-resolution WRF wind field. The Lagrangian particles are traced in time and space as a proxy of the fire smoke plume. The hourly updated High Resolution Rapid Refresh (HRRR) atmospheric model is used as boundary condition forcing. The results of case studies (Camp/Tubbs fire?) are compared with satellite observation (absorbing aerosol index, CO, NO2, and aerosol optical depth). This methodology can be implemented for providing high resolution predictions especially for a few hours ahead, facilitate the in-time alarming of communities to be affected by far-away happening incidents, and improvements in the plume-rise parameterization.