On May 11, 2023, the U.S. Environmental Protection Agency (EPA) released its proposed new rules designed to further reduce emissions of greenhouse gases like carbon dioxide (CO2) from coal and new gas-powered power plants. They would rely on existing technologies for implementation, and are designed to reduce emissions through 2042 by more than 600 million metric tons of CO2 (equivalent to roughly 50 percent of the current emissions from automobiles in the U.S.). Estimates of the expected net direct climate and health benefits exceed $80 billion over the same time period.
These benefits are, however, significant underestimates, because they do not account for obvious co-benefits that would be derived from reductions in other unhealthy pollutants.
Take, for example, the damages caused by the growing list of enormous wildfires across the country. They are mentioned without detail or fanfare on page 46 of the rules document: “Wildfire smoke degrades air quality increasing health risks, and more frequent and severe wildfires due to climate change would further diminish air quality, increase incidences of respiratory illness, impair visibility, and disrupt outdoor activities, sometimes thousands of miles from the location of the fire.”
It seems to me that reviewers of the proposed rules should know more about what lies behind this statement. First of all, wildfires are becoming more extreme, more frequent and sometimes concurrent. In August of 2022, for example, five of the largest six wildfires in California recorded history (including the largest ever) were all burning at the same time. The power of each was enhanced by a long-term drought accompanied by extreme heat and a 10-fold increase in the incidence of dry lightning strikes over the forests. As well, much of the forested region was dotted with large swaths of dead trees owing to an ongoing, widespread and devastating bark beetle infestation. At the same time, large wildfires raged up the coast in Oregon, Washington, and British Columbia.
Detection of these fires was easy, of course, but so is attribution to climate change. Each of the triggers listed above are signatures of climate change, and the causal link has been established with very high confidence. Because they happened simultaneously, their impacts were compounded.
There is also ample evidence, as noted in the draft EPA proposal, that damage from wildfires was not confined to the narrowly defined areas actually affected by the fires. In a comprehensive study published on Feb. 17, 2023, Jeff Wen and colleagues used a severity index to identify the nine most severe wildfires that occurred in the United States from 2006 through 2020. Their index reflected the amount of smoke, the populations affected, and the total number of exposure days distributed across the country.
Six of the nine fires mentioned in their list occurred in 2020, and another occurred in 2018. Of the six from 2020 that burned in California, three had plumes that extended into New England: the August Complex fire (still the largest in California recorded history); the Creek fire; and the Claremont fire. The other three had plumes that extended across the middle of the country west of the Mississippi River; two were also in California (the Dolan fire and the Bobcat fire) while the third was the Santian fire in Washington. The Ranch fire in California is the 2018 entry to their list; its plume also extended to the Mississippi. From personal experience, I know that the 2022 California fires in August extended to Washington, D.C., with enough density to turn the sunsets orange.
It should also be noted that this phenomenon is not confined to the United States. The boreal forests across the entirety of the northern hemisphere are now burning at heretofore unobserved rates. Boreal forest wildfires had typically accounted for 10 percent of the planet’s annual fire-related pollution; in 2021, though, they contributed an unprecedented 21 percent.
The EPA proposal is surely onto something. Readers and reviewers should take account of the effect of these associated benefits, though mentioned only casually, to understand that the true total benefits of the proposed new rules will be more than $80 billion — in the U.S. and around the world.
Gary Yohe is the Huffington Foundation Professor of Economics and Environmental Studies, Emeritus, at Wesleyan University in Connecticut. He served as convening lead author for multiple chapters and the Synthesis Report for the IPCC from 1990 through 2014 and was vice-chair of the Third US National Climate Assessment.