Scientists Fly Into Wildfire Firestorm Clouds in Breakthrough Research Mission

As wildfires grow larger and hotter around the world, a team of researchers has embarked on an unprecedented airborne mission to study the severe storm clouds that form over intense blazes. Known as pyrocumulonimbus, or pyroCb, these firestorm clouds can pump as much smoke into the stratosphere as a volcanic eruption while generating extreme weather phenomena including dry lightning and firenadoes. Because much about their inner workings remains unknown, predicting their behavior poses a significant danger to residents and emergency crews.

This summer, a multi-year collaborative project called the Injected Smoke and Pyrocumulonimbus Experiment, or INSPYRE, deployed a pair of research aircraft to fly over, around, and directly into active wildfire smoke plumes. The mission is led by scientists from NASA, the U.S. Naval Research Laboratory, and the National Center for Atmospheric Research. According to NASA Goddard Space Flight Center research physical scientist John Yorks, being able to sample inside the plumes, inside the clouds, and above them simultaneously is something researchers have never achieved before.

Describing the operational scope, NRL meteorologist and principal investigator David Peterson compared the project to a well-organized storm chase targeting storms triggered by wildfires. Peterson noted that the team's initial deployment successfully wrapped up after navigating what he called an unworldly experience of flying through dark, orange-hued smoke and sampling the tops of the clouds. The project involves a coordinated effort of at least 150 personnel on the ground and in the air, utilizing truck-mounted radar and lidar alongside specialized aircraft.

NASA's Earth Resources-2 plane operated as a steerable satellite high above the weather, while the National Center for Atmospheric Research Gulfstream V aircraft flew through the smoke below. Inlets on the Gulfstream V pulled outside air into onboard instruments to measure chemicals, aerosols, and water vapor. During the final week of this year's deployment, crews tracked a smoke plume originating from a massive firestorm cloud in Siberia that crossed the Pacific Ocean and reached as far as Idaho, representing what Peterson described as the most comprehensive sampling of such an event to date.

Firestorm clouds form when hot, dry, windy conditions with abundant fuel create dense smoke plumes that rapidly carry water vapor and smoke particles high into the atmosphere. As the water vapor cools and condenses, a pyroCb cloud forms. Researchers explain that these formations act like giant chimneys, amplifying weather events by orders of magnitude and creating hazardous conditions on the ground. Dry lightning can ignite new fires miles away, while strong downdrafts produce storm-force winds that endanger firefighters. Furthermore, the thick smoke and cloud cover obscure the flames, complicating evacuation efforts.

While more commonly observed in North America and Australia, pyrocumulonimbus clouds are increasingly appearing in other regions, including Europe. France documented its first recorded pyroCb cloud in July amid record continental heat. Over the past decade, major events have pushed massive quantities of smoke to high altitudes, rivaling or exceeding volcanic eruptions. This includes Australia's devastating 2019-2020 Black Summer bushfire season, which produced a super outbreak of pyroCb clouds, including one plume that persisted in the Southern Hemisphere for over a year.

Despite their impacts, firestorm clouds have only been studied intensively for about 15 to 20 years, leaving significant gaps in understanding how they form and interact with regional meteorology. While satellites have long provided top-down observations, scientists previously lacked direct in-situ data from within the clouds. Ziming Ke, an assistant research scientist at the Desert Research Institute who led a 2025 study simulating firestorm clouds using an Earth system model, compared the previous lack of visibility to looking inside a smoky house.

Researchers are particularly focused on analyzing aerosols such as black carbon, or soot, which absorbs solar radiation and generates heat. Chemistry professor Anne Perring of Colgate University noted that a primary objective is understanding how efficiently black carbon moves through the system and whether it survives into the upper atmosphere to alter atmospheric chemistry. Better data on particle sizes and ice crystal formation will allow forecasters to improve computer models, predict lightning, and better forecast smoke dispersion and temperature effects.

With this year's flights concluded, the INSPYRE team is shifting its focus to detailed data analysis. Researchers plan to evaluate what was captured successfully, identify remaining gaps, and prepare for subsequent deployments next year to continue refining their predictive models.