Critics of mainstream climate science and allies of the fossil fuel industry are taking aim at a prominent expert who’s helping coordinate the next United Nations review of global climate research, arguing that her work aims to bolster multibillion-dollar lawsuits against oil and gas companies.
In an August New York Post op-ed, Roger Pielke Jr., a political scientist at the conservative think tank American Enterprise Institute, raised concerns about the appointment of Friederike Otto as a coordinating lead author for the seventh assessment report of the influential Intergovernmental Panel on Climate Change.
The criticism is aimed at extreme weather attribution, a popular field of research that studies whether and to what degree human-caused global warming has made an extreme weather event, such as a heat wave or heavy rain, more severe or likely to occur. Otto co-founded World Weather Attribution, which develops analyses showing climate’s role in extreme weather events.
Attribution science has been cited in congressional hearings and included in legislation to highlight the links between extreme weather events and climate change. The findings have also been included in lawsuits that seek to hold fossil fuel producers liable for the costs of dealing with climate change — and have drawn the scrutiny of the Trump administration.
Pielke said that Otto’s inclusion in the IPCC report could harm the international scientific body’s reputation.
By putting Otto — a climate science professor at Imperial College London — and her “fellow travelers in charge of the IPCC’s chapter on extreme events,” he wrote, “the IPCC is signaling that media hits, climate litigation, and energy advocacy trump rigorous science.”
Energy in Depth (EID), the advocacy arm of the Independent Petroleum Association of America, amplified Pielke’s call last week, saying Otto’s involvement raises concern the IPCC’s “traditionally neutral assessments could be hijacked by climate litigation supporters.”
Otto said Pielke’s argument that event attribution was inspired by litigation against the oil industry drew on comments he’d taken out of context. She told POLITICO’s E&E News that Pielke was referring to a comment she made about a 2003 paper by Myles Allen, a climate expert at Oxford University, that raised the idea of suing polluters for damages related to global warming. But it “obviously doesn’t mean that everything subsequently has been done for litigation,” Otto said.
“As an author on IPCC, I will be assessing peer-reviewed science,” she added. “And there are many, many peer-reviewed studies that show how climate change has affected extreme weather events.”
The criticism comes as the Trump administration is working to discredit established climate science, in part by producing its own reports that mainstream climate researchers say cherry-pick studies to provide an incomplete picture of how the burning of fossil fuels and other human activities are warming the planet.
A task force whose members were selected by Energy Secretary Chris Wright took aim at the IPCC in a July report that has been criticized by climate scientists as disinformation. Some researchers said their work was misrepresented in the report.
The DOE report argued that the world is on track for less warming than the IPCC’s worst-case scenarios predicted and that its “studies have led the public to believe that climate change is more harmful than it actually is.”
The IPCC’s worst-case scenario assumes world leaders will take no additional steps to address climate change in the coming decade, leading to as much as 5 degrees Celsius (9 degrees Fahrenheit) of warming by the end of the century. While this scenario is unlikely to occur, the latest IPCC report said rising temperatures are already having catastrophic effects.
The IPCC publishes its report every five to seven years, providing a foundational assessment of the latest climate science by hundreds of experts who evaluate thousands of research papers.
Otto will co-coordinate the chapter on changes in regional climate and extreme weather.
Rachel Cleetus, senior policy director with the climate and energy program at the Union of Concerned Scientists, an environmental group that has supported climate litigation, called the criticism against Otto a “deliberate mischaracterization” of her research and the broader IPCC undertaking.
“This is not a process that individual scientists hijack and use for their own purposes,” Cleetus said.
The IPCC does not conduct new research. It relies on hundreds of scientists to synthesize thousands of peer-reviewed studies, and its work is based on consensus so that no single author controls the process. The IPCC also has no role in determining whether the science it assesses is used in lawsuits, Cleetus said.
“But it is a very, very important way in which the world, the public, policymakers, can understand what the latest state of the climate science is,” Cleetus said of the IPCC assessments. “And there’s a whole industry of people, many of them with fossil fuel ties, who are trying to deny those scientific realities.”
The fossil fuel industry and the Trump administration have recently escalated efforts to quash a raft of climate litigation that could leave oil companies on the hook for billions. Since 2017, more than three dozen lawsuits have been filed by cities, counties, states and tribes accusing the oil and gas industry of knowing about the dangers of burning fossil fuels — but failing to warn the public.
The Trump administration has taken two states to court in an effort to prevent them from filing climate liability lawsuits and has asked the Supreme Court for relief.
Otto’s extreme event attribution work has been cited in a number of the climate lawsuits against the oil industry, EID noted. That includes a $51 billion lawsuit filed by Multnomah County, Oregon, accusing Exxon Mobil, the American Petroleum Institute and hundreds of other defendants of contributing to a deadly 2021 heat wave.
“Placing an advocate of litigation-driven science at the helm of the IPCC’s extreme weather chapter risks turning the world’s most trusted climate referee into an arm of climate litigation,” EID wrote last week.
EID, which frequently critiques climate litigation efforts by governments and tracks groups that support those efforts, has long questioned attribution science as politically motivated, arguing that the authors of studies aren’t impartial scientists but climate activists who are biased against the fossil fuel industry.
‘Nothing to do with litigation’
Jakob Zscheischler, an earth system scientist at the Helmholtz Centre for Environmental Research in Germany and an author of the upcoming chapter with Otto, said he had “absolutely no concerns” about her appointment as a coordinating lead author or the legitimacy of extreme event attribution.
“It helps us [disentangle] which aspects of specific types of extreme weather events are changed by anthropogenic climate change and which aspects are not, with a level of detail that was not possible before,” Zscheischler said in an email.
He and Andrew Dessler, a climate scientist at Texas A&M University, noted that the impact of a single author on the IPCC is limited by having other lead authors on the same chapter and several rounds of external reviews.
Dessler said there is a cadre of critics ready to dispute the connection between extreme events and climate change — even in a report that is still years away from release. The IPCC has not yet confirmed a timeline for the seventh assessment, but it’s expected to be completed around 2029.
The IPCC defended the author selection process, pointing to a fact sheet that says lead authors are nominated by experts, IPCC member governments and observer organizations.
A “balanced assessment of the full range of scientific views, protected from the influence of special interests, is supported through the method of author team selection, multiple rounds of review of each report” and the group’s conflict of interest policy, the IPCC added.
The IPCC reports are organized in three working groups, and each group has a series of chapters. Otto will serve as one of three coordinating lead authors for Chapter 3 of Working Group I on current climate impacts on a regional scale. That includes extreme weather events.
Otto said coordinating authors are expected to make sure the chapter is delivered according to the outline agreed to by global governments, adding that her work with the IPCC has “absolutely nothing to do with litigation.”
The correlation between individual weather events and rising temperatures has been used in some climate liability lawsuits, Otto noted. But she said her critics have sought to combine various statements she has made over the past 10 years and used them out of context.
Otto was previously an author on part of the IPCC’s sixth assessment report published in 2021 and the accompanying synthesis report published in 2023.
Climate change ‘signal’
Pielke told E&E News that the IPCC has traditionally “played it pretty straight” when it comes to establishing links between climate change and extreme weather. But he said extreme event attribution is a departure from the IPCC’s traditional framework for detection and attribution.
That approach refers to the influence of global warming on long-term, large-scale trends in weather or other climate impacts, rather than individual weather events. It’s a strategy that predates extreme weather event attribution and is separate from that field.
Pielke has for years argued that climate activists exaggerate the IPCC’s findings on the links between climate change and long-term trends in extreme weather. And in his recent op-ed, he argued that extreme event attribution is “a cottage industry of promotional studies” designed to replace the IPCC’s conventional methods.
But most climate scientists say extreme event attribution complements — and agrees with — long-term detection and attribution studies. In its most recent assessment report, the IPCC’s chapter on extreme events found that climate change has influenced a variety of weather events.
Pielke, alongside other researchers who are skeptical of mainstream climate science, has in the past sought to back up his claims with an IPCC chart that indicates many forms of extreme weather have no “emergence of a signal” linking them to climate change. It’s an argument the DOE’s climate report used as well.
Many climate scientists say that’s a misleading argument. They have noted that an emerging signal refers to a specific kind of statistical pattern in extreme weather — a trend that has grown so large that it has moved outside the range of being possible without climate change. The absence of this signal doesn’t mean that events aren’t worsening or that climate change isn’t influencing them, researchers say.
‘Fundamental science’
World Weather Attribution was founded to provide scientific evidence in the aftermath of an extreme weather event, Otto said, adding that the methodology it uses and many of its studies have been peer reviewed.
“The numbers have never changed through the peer-review process,” Otto said. “Everything we do is super transparent, so all the data is freely available. It is very fundamental science.”
World Weather Attribution publishes papers that show climate change does play a role in extreme weather events — but also that it sometimes does not play a role, or that the data isn’t conclusive, Otto said.
“The aim with World Weather Attribution is to understand how climate change impacts people today, and that is what we do,” she added.
