Western wildfires are producing massive plumes of smoke that have, in recent years, clouded eastern skies. But a new study finds that, paradoxically, heat from fires is reshaping weather patterns in ways that are actually improving overall air quality on the East Coast.
The modeling study reveals that the intense heat rising from wildfires weakens the flow of cool, moist air from the West to the Great Plains. Warmer, drier air on the Great Plains, in turn, draws in winds from the East. Easterly winds not only suppress the spread of smoke from western fires, they also bring in moisture from the Atlantic Ocean. And that extra moisture fuels rainfall on the East Coast, cleaning particulate pollution from the air.
Extreme wildfires lead to a decline in eastern pollution not just while forests are ablaze but throughout the fire season, according to the study. The findings may come as a surprise to New Yorkers who have seen skies turn hazy as smoke blew in from fires in California. But the net effect of western fires, the study finds, is to make eastern air cleaner.
By helping to clear pollution, western wildfires are preventing 2,900 early deaths yearly on the East Coast, authors estimate. The findings, published in the journal Science, “show that local wildfires may unexpectedly have far-reaching effects on weather in distant regions.”
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