Monterey scientist a leader in new wildfire research
MONTEREY >> Research being conducted in Monterey could unlock secrets about the effects massive wildfires have on everything from climate to high altitude pollution.
Dave Peterson, a meteorologist and atmospheric scientist with the U.S. Naval Research Laboratory, just returned to Monterey from a major endeavor involving hundreds of scientists and computer modeling experts, where he led a team of fire and weather forecasters.
The research venture, called the NASA/NOAA Field Campaign FIREX-AQ, studied a phenomenon that occurs in several wildfires that can affect everything from firefighting efforts to climate conditions.
Firefighters involved in the 2013 Rim fire near Yosemite and the 2018 Carr fire outside of Redding have described the blazes as having created their own weather. Thunderstorms, to be exact. When the conditions are right, such as the level of heat present and the amount of moisture in the air, such fires produce what Peterson calls massive pyrocumulonimbus clouds, or pyroCbs.
Cumulonimbus clouds are those white, puffy, towering vertical clouds. PyroCbs are similar, but they are being generated by uplift from the center of wildfires. Think of pyroCbs as massive chimneys sucking smoke and other particles vertically into the atmosphere — sometimes as high as Mount Everest. Like any thunderstorm, pyroCBs can produce their own lightning.
Peterson led the fire and forecasting team out of Boise, Idaho, that studied one of those massive smoke elevators. He and his team accomplished the first successful forecasting of a pyroCb generated from a wildfire in Washington state Aug. 8.
“This smoke is rapidly injected into higher altitudes that produce dirty clouds but no precipitation,” Peterson said Thursday from his Monterey lab. “It’s like an engine pumping smoke into these higher altitudes for anywhere from a few minutes to an hour or more.”
Higher is the keyword. Satellite images and data have recorded these monsters injecting smoke into the lower rungs of the stratosphere, which begins at about 33,000 feet. The summit of Mount Everest is at 29,029 feet. The ramifications of such events are what’s being studied.
The campaign was not about scientists sitting around in front of computers, although there was a lot of that. Peterson and other atmospheric scientists, chemists and a host of other disciplines hopped aboard a DC-8 outfitted with a bevy of sensitive instrumentation and flew into the cloud. Chemists were on board to measure the composition of the smoke to see if it had changed at all during the process of being injected into the atmosphere.
Researchers don’t yet know how toxic wildfire smoke is. Kent Pinkerton, a professor at UC Davis, said there is a greater concentration of particles in wildfire smoke that vary in size and have different constituents that may create a more toxic combination than researchers find in other sources of air pollution.
“We don’t have the complete data on the complexity of wildfire smoke composition that may contain chemicals that are quite toxic,” Pinkerton said.
Consider the fire in Paradise in November that burned plastics, asbestos and even lead as homes were consumed.
This matters because pyroCbs can travel vast distances. Peterson noted that the scientific investigations began in the early 2000s, when better satellite technology identified data and images of smoke in the stratosphere. In 2017, a wildfire in British Columbia created a pyroCb that was caught in high, fast winds that resulted in smoke covering most of the Northern Hemisphere, essentially circling the globe.
“This is all new science,” Peterson said. “We’re asking questions like how wide can they get and how hot is hot enough to create them?”
Now that data has been collected from the Washington state pyroCb, it will take months for it to be analyzed to perhaps answer some of those questions. In the meantime, other scientists believe climate change is fueling much of the volatile and deadly fire seasons seen in the past few years in California, so more pyroCbs are likely to form above wildfires that are sure to come.