On September 5, 2020, California’s Creek Fire produced a thunderstorm so intense that it created its own weather system. This phenomenon, known as a pyrocumulonimbus cloud, has become more common during fire seasons in the western United States and can have significant effects on air quality, weather patterns, and climate. Until recently, scientists had difficulty simulating these wildfire-induced storms in Earth system models.
A new study published on September 25 in Geophysical Research Letters marks the first time researchers have successfully recreated these storms within an Earth system model. The research was led by Ziming Ke of the Desert Research Institute (DRI) and involved scientists from Lawrence Livermore National Laboratory, University of California Irvine, and Pacific Northwest National Laboratory.
The team’s model accurately reproduced the timing, height, and strength of the Creek Fire’s thunderhead—one of the largest pyrocumulonimbus clouds observed in the United States according to NASA. It also simulated multiple thunderstorms generated by the 2021 Dixie Fire under different conditions. The findings highlight how moisture lifted into higher atmospheric layers by terrain and wind contributes to storm development.
“This work is a first-of-its-kind breakthrough in Earth system modeling,” Ke said. “It not only demonstrates how extreme wildfire events can be studied within Earth system models, but also establishes DRI’s growing capability in Earth system model development — a core strength that positions the institute to lead future advances in wildfire–climate science.”
Pyrocumulonimbus clouds inject smoke and moisture into the upper atmosphere at levels similar to small volcanic eruptions. These aerosols can remain for months or longer and alter stratospheric composition. When transported to polar regions, they influence Antarctic ozone dynamics and contribute to changes in cloud cover and surface reflectivity, which may accelerate ice melt.
Scientists estimate that tens to hundreds of such storms occur worldwide each year. As wildfires become more severe due to changing climate conditions, their frequency is expected to increase further. The inability to simulate these events until now has limited understanding of their impact on global climate systems.
The research used the Department of Energy’s Energy Exascale Earth System Model (E3SM) to capture interactions between wildfires and atmospheric processes.
“Our team developed a novel wildfire–Earth system modeling framework that integrates high-resolution wildfire emissions, a one-dimensional plume-rise model, and fire-induced water vapor transport into DOE’s cutting-edge Earth system model,” Ke said. “This breakthrough advances high-resolution modeling of extreme hazards to improve national resilience and preparedness, and provides the framework for future exploration of these storms at regional and global scales within Earth system models.”
The full study is available online: https://agupubs.onlinelibrary.wiley.com/doi/10.1029/2024GL114025
Study authors include Ziming Ke (DRI/Lawrence Livermore National Lab), Qi Tang (Lawrence Livermore National Lab), Jishi Zhang (Lawrence Livermore National Lab), Yang Chen (UC Irvine), James Randerson (UC Irvine), Jianfeng Li (Pacific NW National Lab), Yunyan Zhang (Lawrence Livermore National Lab).
Desert Research Institute is Nevada's non-profit research organization founded in 1959 with over 600 staff members across Reno and Las Vegas campuses conducting more than $52 million in sponsored research during 2024 focused on improving human lives.