Images of vast clouds of wildfire smoke towering into the sky have become all too familiar during the recent years of record-breaking fires across the western United States and elsewhere. Now, a team of atmospheric scientists has demonstrated these plumes have major impacts on the stratosphere and climate. The results were just published in the journal Science.
Big wildfires can send smoke plumes to immense heights. These towering clouds, called pyrocumulonimbus or pyroCbs, are generated when the intense heat of a wildfire triggers a huge thunderstorm that carries smoke into the stratosphere, five to seven miles above the surface.
In 2017, a U.S. airborne mission to study the atmosphere over the remote oceans intersected with smoke from an enormous pyroCb event in the Pacific Northwest. The smoke was so widespread that remote sensing instruments around the globe monitored it for more than eight months. Measurements showed that it and several additional Northern Hemisphere pyroCb events that year dominated contributions of black carbon and organic carbon to the lower stratosphere, outpacing human emissions from vehicles, industry, heating, cooking and agricultural land-clearing. The net effect was to cool the planet.
Read more at: Columbia Climate School
The Williams Flats fire in northeastern Washington state generated a fire cloud, or pyroCb, that injected smoke into the stratosphere on August 8, 2019. A NASA aircraft flew in to investigate. (Photo Credit: David Peterson, NRL)