Australia

‘Fire-breathing dragon clouds’: explaining the phenomenon caused by wildfires

NASA calls them “fire-breathing cloud dragons.”

Aerial images of the McKinney fires taken this week captured an increasingly common phenomenon.

The nearly uncontained fires raging in California’s Klamath National Forest are the latest to cause clouds this year. Derek Maria, a University of Utah researcher who recently co-authored the paper, described them as similar to thunderstorms caused by fire. Show how the smoke is risingand they are a serious concern for firefighters.

Map of the McKinney Fires in Northern California.

Thunderstorms are usually caused by large storm systems such as cyclones and cold fronts. But if the fire is big enough and there’s enough moisture in the atmosphere, the smoke can mix with the thunderstorm clouds and create a thunderstorm of its own. “Essentially, the fire is creating its own weather,” Maria said.

Pyrocumulonimbus clouds are feared for several reasons. When they form over fire, clouds can spread the flames below even faster. Pyrocumulonimbus clouds tend to be drier and tend to have less rain, Maria explained. The result is unpredictable fires under the clouds, and lightning strikes can even start new fires.”This is what happened in British Columbia in the summer of 2021, when a single fire 700,000 lightning strikes.

Pyrocumulonimbus clouds are produced by the intense Ororal Valley wildfires burning south of Canberra, Australia in 2020. Photo: Brooke Mitchell/Getty Images

Fires can also move erratically due to the vacuum created between the clouds and the ground. David Peterson, a meteorologist at the U.S. Naval Research Laboratory, said the hotter a wildfire burns, the more updrafts it creates. virtual press conference “These are pushing the smoke upwards at extreme velocities, like they are jetting smoke at altitudes higher than the cruising altitude of a jet,” Peterson said. “So we’re talking potentially 50, 60,000 feet.”

Pyrocumulonimbus clouds are becoming more common, throwing more pollutants into the upper atmosphere. As the fire grows and the fuel dries up, it produces more heat and smoke, Maria said.

Last month, lightning flashed in Siskiyou County, California. A lightning strike set off a new wildfire with the crew fighting the nearby McKinney Fire.
Last month, lightning flashed in Siskiyou County, California. A lightning strike set off a new wildfire with the crew fighting the nearby McKinney Fire. Photo: Noah Berger/AP

In some cases, tall plumes and fire convection can push aerosols into the stratosphere. moderate volcanic eruption – Can push particles into jet streams and affect air quality on a continental scale. That’s what happened when the smoke from the West Coast fires swept up to New York City.

2019 NASA Researcher I flew in an airplane through the fire clouds Understand smoke chemistry and better understand its impact on air quality and climate.

Scientists are still learning about storms caused by fires. Maria and his colleagues hope to help fire managers and firefighters by developing a method to predict when pyrocumulonimbus clouds will appear.

And they want to know how clouds cause further warming in the atmosphere. Smoke particles contain a lot of black carbon, which can cause warming when exposed to sunlight at high altitudes.

“Seeing more smoke injected into the stratosphere could warm the atmosphere even more,” he said. “If we see this more frequently, it could have long-term warming effects.”

‘Fire-breathing dragon clouds’: explaining the phenomenon caused by wildfires

Source link ‘Fire-breathing dragon clouds’: explaining the phenomenon caused by wildfires

Back to top button