Integrating Fire-Induced Meteorological Changes into Plume Rise Modeling for Extreme Wildfire Simulations

Abstract. Wildfire emissions are a major environmental concern, especially as climate change increases the frequency of extreme events. Our study investigates the limitations of the widely used Freitas plume-rise model during the Australian New Year’s wildfires of 2019/2020, focusing on how accounting for fire-atmosphere feedbacks in the host model affects plume rise. Simulations were conducted at a 6.6 km grid resolution, where convection is parameterized but fire-induced meteorological effects remain significant. Including fire-induced moisture release led to increased cloud formation, but had minimal impact on plume dynamics. In contrast, accounting for fire-induced heat release significantly increased the plume height due to enhanced buoyancy and cloud formation, even without added moisture.

Simulating aerosol–radiation interactions initially reduced injection height, as solar absorption by dense aerosols stabilized the atmosphere. However, a lofting effect emerged from the second day onward. The combined simulation—incorporating heat and moisture release and aerosol-radiation interaction—produced the highest plume rise and best matched satellite observations, including the aerosol layer in the upper troposphere/lower stratosphere. The effects were strongest on the first day, when fire intensity peaked. For less intense fires, the Freitas plume-rise model performed well without additional feedback mechanisms.