In April 2024, the prestigious journal Nature released a study finding that climate change would cause far more economic damage by the end of the century than previous estimates had suggested. The conclusion grabbed headlines and citations around the world, and was incorporated in risk management scenarios used by central banks.
On Wednesday, Nature retracted it, adding to the debate on the extent of climate change’s toll on society.
The decision came after a team of economists noticed problems with the data for one country, Uzbekistan, that significantly skewed the results. If Uzbekistan were excluded, they found, the damages would look similar to earlier research. Instead of a 62 percent decline in economic output by 2100 if carbon emissions push global temperatures up by 8.5 degrees Celsius, global output would be reduced by 23 percent.
Of course, erasing more than 20 percent of the world’s economic activity would still be a devastating blow to human welfare. The paper’s detractors emphasize that climate change is a major threat, as recent meta analyses have found, and that more should be done to address it — but, they say, unusual results should be treated skeptically.
“Most people for the last decade have thought that a 20 percent reduction in 2100 was an insanely large number,” said Solomon Hsiang, a professor of global environmental policy at Stanford University who co-wrote the critique published in August. “So the fact that this paper is coming out saying 60 percent is off the chart.”
Retractions have become more common in recent years, according to Retraction Watch, an organization that tracks corrections in scientific journals. But they are still rare, amounting to about one in 500 articles published.
Economists have long struggled to incorporate granular, sometimes subtle impacts of climate change into models that forecast far into the future, especially when combining them with something as complex as the global economy.
The study was led by Leonie Wenz, an economist at the Potsdam Institute for Climate Impact Research in Germany, and Maximilian Kotz, who was a postdoctoral researcher at the institute. The team devised several novel techniques to more comprehensively capture climate change’s economic ramifications.
They used a painstakingly compiled data set of economic conditions in geographic areas smaller than countries, like states and provinces. They incorporated a range of climatic conditions, such as rainfall and heat waves, rather than just average temperatures. And they took into account the effects of extreme weather events over a decade, rather than assuming they dissipated quickly.
“We were trying to understand how long we can observe these impacts in the data,” Ms. Wenz said. “That led to higher damage magnitudes compared to work that wasn’t taking these more persistent effects into account.”
It also led to a striking comparison with the costs of avoiding catastrophic warming. Damages that are essentially baked in over the next 25 years will cost six times the money it would take to lower emissions enough to limit the world to 2 degrees Celsius of warming, the goal set by the Paris Climate Accord.
The paper’s ambitious scope attracted the Network for Greening the Financial System, a network of mostly European central banks and financial regulators, as it updated a guide that is used for stress testing whether banks would remain sound as climate damage mounted. After questions were raised, the organization added a disclaimer to the guide, and said it would rely on a wider range of other research for future updates.
The paper was also cited by the Organization for Economic Cooperation and Development, and was in the top 5 percent of journal articles tracked by Altmetric, a measurement tool for research impact. Carbon Brief, a climate-focused news outlet, found it was the second most referenced climate paper in 2024.
But the criticisms mounted. A few days after the Stanford researchers’ comment published over the summer, another came from a colleague of the authors at the Potsdam Institute for Climate Impact Research, Christof Schötz. He focused on a common problem when teasing out the impact of one variable for many different geographical points: Nearby places often behave similarly to each other. The authors’ failure to account for those correlations, Mr. Schötz argued, made the results so uncertain that they were essentially worthless.
“The paper does not provide additional evidence of economic damages from climate change, nor can it serve as a basis for reliable future projections,” he said in an email.
In response to the counterarguments, Mr. Kotz and Ms. Wenz made corrections that they said altered the results only modestly, with a slightly larger uncertainty range and slightly smaller economic impact by the end of the century. “There are small quantitative changes, but these general qualitative messages are very much the same,” Mr. Kotz said.
They plan to revise the paper and resubmit it.
Some researchers say it is still possible that climate change could exact damages as large as the Potsdam researchers originally found. Scientists in the field are figuring out ways to incorporate more and more ripple effects — the impact of wildfire smoke on respiratory health, for example, or how sea level rise affects home values.
Timothy Neal, an economist at the University of New South Wales, recently published a paper finding climate change will cause global disruptions that will constrain economic growth even in countries where the weather is less extreme. The results suggest a 40 percent loss in 2100 if carbon emissions remain high.
“Damages are very likely to be undercounted in the existing literature,” Mr. Neal said.
However, climate economists are concerned about maintaining credibility, especially while the Trump administration is defunding climate science and discarding efforts to lower emissions.
Lint Barrage, chair of energy and climate economics at ETH Zurich, thinks the retracted paper has other methodological problems having to do with country-level inflation calculations that bias the results upward. Mr. Kotz and Ms. Wenz’s correction note shows that their findings would be “substantially smaller” if they used Ms. Barrage’s preferred approach, which she finds frustrating.
“It can feel sometimes, depending on the audience, that there’s an expectation of finding large estimates,” Ms. Barrage said. “If your goal is to try to make the case for climate change, you have crossed the line from scientist to activist, and why would the public trust you?”
As one remedy, some researchers recommend not trying to do so much in the first place. Noah Kaufman, a senior research scholar at Columbia University’s Center on Global Energy Policy who worked in the Biden White House, believes studying specific questions — like how to decarbonize while keeping electricity affordable — is more useful than projecting macroeconomic impacts decades down the road.
“There are just a lot of examples in the world where we do recognize that there are large risks, but we don’t pretend we can optimize our response to them,” Mr. Kaufman said. “We just try to avoid them in a reasonable way.”
Lydia DePillis reports on the American economy for The Times. She has been a journalist since 2009, and can be reached at [email protected].
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