The 3D Dynamics of a Wildfire Plume Extending Across the Top of the Planetary Boundary Layer Using an Airborne Doppler Lidar

Abstract

As wildfire pervasiveness increases with a changing climate, there is a need to develop new techniques with emerging technologies to understand the interaction between wildfires and the surrounding atmosphere at a high spatiotemporal resolution. The Fire Influence on Regional to Global Environments and Air Quality (FIREX-AQ) experiment conducted in 2019 focused on wildfires using several measurement platforms aboard aircraft. In this study, we interpret wind measurements across a smoke plume transported vertically and advected along the top of the boundary layer (BL) from an airborne Doppler lidar (DL). Flight transects parallel and perpendicular to the orientation of the plume enabled the characterization of key features such as a fire-induced spanwise vortex, large downdrafts that modified the smoke plume, and the evolving velocity structure at different distances downwind of the fire-induced convergence zone (FICZ) at an unprecedented horizontal and vertical resolution of 10s of meters.