His family confirmed his death but did not cite a cause.
Dr. Michaels, who spent decades as a professor of environmental sciences at the University of Virginia and as Virginia’s state climatologist, was one of the most prominent contrarian voices in political and policy discussions surrounding climate change.
He did not dispute the rising temperatures widely documented around the planet, nor did he deny a human role in the phenomenon. “I believe in climate change caused by human beings,” he told The Washington Post in 2006. “What I’m skeptical about is the glib notion that it means the end of the world as we know it.”
His stance, and the forceful way he promoted it in his frequent media appearances, attracted the condemnation of scientists and environmentalists who accused Dr. Michaels of obstructing policy changes that might mitigate the threat posed by climate change. They noted his association with the libertarian Cato Institute in Washington, where he was for a period director of the Center for the Study of Science, as well as his financial backing by the fossil fuel industry, to question the integrity of the research he cited in support of his positions.
But with his combination of academic bona fides, his state title and his flair in the boxing ring of policy debate — he described former vice president Al Gore, a leading climate change activist, as a “scientist wannabe” and denounced the “self-selected community of climate boffins” and “keepers of the environmental-gloom paradigm” — Dr. Michaels proved an often effective champion of his cause.
“He was just a born fighter,” said Robert Balling, a professor at Arizona State University who co-wrote books with Dr. Michaels including “The Satanic Gases: Clearing the Air About Global Warming” (2000) and “Climate of Extremes: Global Warming Science They Don’t Want You to Know” (2009).
“I knew people who refused to debate him,” Balling added, recalling the frustrations of some scientists, highly trained in their fields but unpracticed in the political arena, who were called upon to spar with him.
Dr. Michaels wished to be known not as a climate change “skeptic,” but rather as a “lukewarmer.” That term, said Judith Curry, an atmospheric scientist and professor emerita at Georgia Tech, denotes someone who argues that global warming is caused only partly by human activity, with natural climate variability as another contributing factor.
He was named Virginia state climatologist by Gov. John N. Dalton, a Republican, in 1980. By all accounts, Dr. Michaels performed ably in that role, once described by The Post as a “cross between a meteorologist and a librarian,” in which he was tasked with gathering and analyzing data on weather across the state.
But as climate change emerged as an issue of increasing urgency, and as scientific agreement coalesced around its human causes, Dr. Michaels became more outspoken in challenging what he regarded as alarmist positions on global warming and regulatory overreach in the effort to combat it.
He argued that the United States should not sign the 1997 Kyoto Protocol to reduce greenhouse gas emissions (the United States ultimately was not a signatory to the agreement) and described the 2016 Paris agreement (which the United States joined under President Barack Obama, left under President Donald Trump and rejoined under President Biden) as “climatically insignificant.”
In 2006, the office of Virginia Gov. Tim Kaine, a Democrat, asked Dr. Michaels to clarify that he did not speak for the state or the governor when he addressed matters related to global warming. Dr. Michaels stepped down from the post and from U-Va. the following year, lamenting what he said was a lack of “academic freedom.”
Dr. Michaels left the Cato Institute in 2019 and joined the Competitive Enterprise Institute in Washington. Responding to critics who noted his funding over the years from coal-burning utilities, he said that he had been “working on climate change long before I worked as a consultant” and that his “views have been quite consistent over that period.”
In his frequent media appearances, he exploited the “norm” that “for every PhD there is an equal and opposite PhD” on the other side of a political issue, Andrew Revkin, a former New York Times journalist who has written about climate change since the 1980s and who now runs a communication innovation initiative at the Columbia Climate School, said in an interview.
“He was artfully accepting the human role in the climate system and artfully always able to present the case for caution or for uncertainty,” but in a way that suited the advocacy and interest groups he worked for, Revkin said.
“He was an excellent writer and verbal communicator, but in my opinion he undermined his own effectiveness by being strident,” David Policansky, a former scholar and senior project director at the National Academies of Sciences, Engineering and Medicine wrote in an email, noting “the risks and rewards of mixing science and politics. A risk is undermining one’s credibility and a reward is influencing policy.”
Patrick Joseph Michaels was born in Berwyn, Ill., on Feb. 15, 1950. His father was a mushroom farmer, and his mother was a homemaker.
Dr. Michaels received a bachelor’s degree in biological sciences in 1971 and a master’s degree in biology in 1975, both from the University of Chicago. He received a doctorate in ecological climatology from the University of Wisconsin at Madison in 1979. He was a past president of the American Association of State Climatologists.
His books included “Sound and Fury: The Science and Politics of Global Warming” (1992), “Meltdown: The Predictable Distortion of Global Warming by Scientists, Politicians, and the Media” (2004) and “Lukewarming: The New Climate Science that Changes Everything” (2016), written with Paul C. Knappenberger.
Dr. Michaels’s marriage to Erika Kancler ended in divorce. Survivors include his wife of six years, the former Rachel Schwartz of Marshall, Va.; two children from his first marriage, Erika Michaels of Waynesboro, Va., and Robert Michaels of Richmond; and two brothers.
Even among those who disagreed intensely with his scientific positions, Dr. Michaels found his defenders.
“He did care about the environment,” said Larry Kalkstein, a professor emeritus of climatology at the University of Delaware and the University of Miami, recalling that he had seen Dr. Michaels “painted unfairly as a … pawn for industry.”
“I never found his gaining money from industry as being a negative,” Kalkstein added, noting his own financial support from environmental groups. “I found that it’s basically the same in my mind.”
“I disagreed with Pat vehemently when it comes to the science and policy implications of climate change,” Michael E. Mann, a professor of atmospheric science at Pennsylvania State University who had earlier worked with Dr. Michaels at the University of Virginia, wrote in an email. “But I always found him to be an amicable colleague during our overlap at U. Va two decades ago.”
At climate conferences, Dr. Michaels was easily identifiable by the green tennis shoes he often wore — a ready-made conversation starter in a world of polarizing debate.
Jason Samenow contributed to this report.