Record heat and growing wildfires are creating firestorms that can generate their own lightning in the skies above the western United States and British Columbia, Canada.
Towering over the burning forests up to 5 miles (8.9 kilometers) in height, these anvil-shaped pyrocumulonimbus clouds – dubbed “fire clouds” – can produce hurricanes and lightning, which can generate even more fires, according to the BBC.
And they are nearly impossible to fight. Nasa calls pyrocumulonimbus “the fire-breathing dragon of clouds,” because they act like a chimney, sucking the smoke and heat from the fire up into the Earth’s atmosphere while hurling thunderbolts, wind, and rain.
Usually, wildfires are driven along by the wind, but a massive blaze can carry so much power and be so hot that its smoke is not pushed to the side. Instead, it forms a plume that rises up about 5 to 10 miles into the sky.
When all that heat and moisture in the plume reaches the Earth’s stratosphere, it can condense and form clouds. Pyrocumulonimbus clouds also tend to form in the afternoon when the fire is at its hottest.
When these fire clouds form over a roaring wildfire, they can make the blaze spread even faster. Sometimes they can also create their own lighting, which can spark more fires. They can even produce rain.
“Later in the afternoon, that cloud will collapse and create a downdraft of heavy smoke, embers, things like that, and it can actually create additional fire behavior,” Lisa Cox, information officer for the western California fires told the Los Angeles Times.
‘Fire-Breathing’ Clouds over Lytton, British Columbia
Temperatures in Lytton, 153 kilometers (95 miles) south of Vancouver, hit 121.2 degrees Fahrenheit (49.5 degrees Celsius) on Tuesday, June 29, – a new national record for Canada.
The heatwave preceded a wildfire that prompted the town’s mayor to issue an evacuation order for all 250 residents. As of Thursday morning, July 1, the 20,000-acre blaze had burned 90 percent of Lytton, according to local outlet City News.
Satellites circling above the Earth were also watching the wildfire in Lytton. Dakota Smith, a meteorologist from Colorado’s Cooperative Institute for Research in the Atmosphere, reported seeing “incredible & massive storm-producing pyrocumulonimbus plumes” on satellite images above Lytton Wednesday.
The 2020 Creek Fire in California
The Creek Fire was a large wildfire that started on September 4, 2020, near Shaver Lake in California. The fire burned 379,895 acres (153,738 hectares) and was declared 100 percent contained on December 24, 2020.
Besides being the fourth-largest wildfire in California’s history, The fire also created a pyrocumulonimbus cloud formation, the largest ever seen in the US – It measured 175,893 acres, or 275 square miles, in size (an area more than three times the size of Seattle, Washington).
Rising temperatures and drier air are associated with more frequent and more intense wildfires. And as wildfires increase in size and severity, fire-generated storms, too, are becoming more common.
In 2002, Canada, the US, and Mexico saw about 17 storms in total. About two decades later, the average number of annual pyrocumulonimbus events had jumped to 25 in western North America alone, Yale360 reported.
