This year, climate research seemed to hit a rough patch. Scientists preparing the next generation of global climate scenarios scrapped the most extreme pathway that had shaped years of academic research, financial risk analysis, media coverage, and advocacy. A prominent study estimating that climate change would cost the global economy $38 trillion per year by midcentury was retracted by the academic journal Nature, while a new study argued that meaningful estimates of climate change’s economic damages lie beyond our analytical capabilities, prompting a Wall Street Journal op-ed headlined “You Can’t Trust ‘Climate Economics.’”
Many on the right quickly claimed vindication. After the worst-case scenario was retired in May, U.S. President Donald Trump declared on social media that climate research had been “WRONG! WRONG! WRONG!” Roger Pielke Jr. of the University of Colorado, a longtime critic of the misuse of extreme climate scenarios, wrote in the Washington Post: “The climate apocalypse isn’t around the corner after all.”
This year, climate research seemed to hit a rough patch. Scientists preparing the next generation of global climate scenarios scrapped the most extreme pathway that had shaped years of academic research, financial risk analysis, media coverage, and advocacy. A prominent study estimating that climate change would cost the global economy $38 trillion per year by midcentury was retracted by the academic journal Nature, while a new study argued that meaningful estimates of climate change’s economic damages lie beyond our analytical capabilities, prompting a Wall Street Journal op-ed headlined “You Can’t Trust ‘Climate Economics.’”
Many on the right quickly claimed vindication. After the worst-case scenario was retired in May, U.S. President Donald Trump declared on social media that climate research had been “WRONG! WRONG! WRONG!” Roger Pielke Jr. of the University of Colorado, a longtime critic of the misuse of extreme climate scenarios, wrote in the Washington Post: “The climate apocalypse isn’t around the corner after all.”
Beneath the bluster, the critics have a point. Too many climate advocates have treated worst-case scenarios as likely outcomes and too often used apocalyptic language that outran the evidence. Claims such as U.S. President Joe Biden’s 2022 warning that “climate change is literally an existential threat to our nation and to the world” overstated the case.
But Europeans sweltering through last week’s deadly heat wave could be forgiven for finding little comfort in that reassessment. Two things can be true at the same time: Some climate rhetoric has outrun the evidence, yet the evidence still points to a far hotter, more dangerous, and more disruptive world well beyond what Europe just endured.
Europe has been baking under record-breaking temperatures. Cities across the continent, where air conditioning is far less common than in the United States, suffered through dangerous combinations of heat and humidity, with hospitals, power systems, transportation networks, and vulnerable populations under severe strain. The Economist estimated that extreme heat such as that Europe experienced last week could cause around 12,000 excess deaths in just three days. Europeans also struggled with soaring energy prices as demand for cooling surged, and some power plants struggled to operate efficiently in the extreme heat.
The reason heat waves are becoming more frequent and severe is well understood: The planet is warming because greenhouse gas concentrations are rising to levels far above those experienced throughout human civilization, largely from the burning of fossil fuels. Europe is warming much faster than the global average, in part because northern latitudes are heating especially rapidly. That means what once counted as exceptional heat is becoming more common, more intense, and more dangerous.
Critics of climate alarmism are right that research and advocacy too often leaned on extreme and unlikely emissions scenarios. For years, an implausibly high-emissions pathway—with assumptions such as a fivefold increase in coal use by 2100—was routinely presented in academic studies, risk reports, and media coverage as a plausible version of the path the world was on.
But the alternative to alarmism is not complacency. The heat gripping Europe is dangerous enough on its own. What makes it even more alarming is that we still do not know how much worse climate change may become, how quickly its effects may compound, or where the thresholds are beyond which societies struggle to adapt.
The same scientific reassessment in May that found the highest-emissions scenario implausible also found that the lowest-emissions scenarios are slipping out of reach. That should give more, not less, cause for concern. On today’s likely trajectory, the world is heading toward roughly 2.5 to 3 degrees Celsius of warming by the end of the century. At those levels, weeks such as these would no longer be exceptional in much of Europe by later this century; they would become recurring features of summer —and the likely harms at these levels of warming go well beyond more sweltering days.
What may matter most is not what climate outcomes are expected but which cannot be ruled out. Temperatures may rise further and faster than anticipated. Ice sheet instability could commit the world to centuries of rising seas. Stresses on infrastructure, water, agriculture, and public health systems could drive migration, economic disruption, and conflict, falling hardest on the countries least able to adapt. None of these outcomes is certain. But all are plausible enough that no responsible risk manager would ignore them.
That is why a new academic paper that purportedly “breaks climate economics,” according to Pielke, is cause for more concern not less. The two economists who wrote it, Finbar Curtin and Matthew Burgess of the University of Wyoming, do not find that the economic harms of climate change are small but rather that the true scale of those damages is highly uncertain and too difficult to quantify. They argue that economic models that generate a false sense of precision obscure more than they reveal.
The Trump administration has drawn precisely the wrong conclusion from the genuine limits of climate economics. In May 2025, the White House directed agencies to stop factoring climate damage estimates into regulatory analyses, arguing that “the uncertainties in performing monetized impacts quantifications are too great.” It then used that uncertainty to justify weakening the climate regulations those estimates had supported. That gets the logic backward.
Uncertainty about climate damages is not a reason to abandon climate safeguards. It is, as Harvard University economist Martin Weitzman showed, a reason to take them more seriously. When catastrophic outcomes are possible but hard to quantify, conventional cost-benefit analysis that ignores such “tail risks” can systematically understate the case for action. The same features that make future climate outcomes so difficult to model—the possibility of extreme and potentially unbounded harms—are precisely what make them too consequential to ignore.
Governments understand this in other domains. They do not wait for precise damage estimates before preparing for pandemics, maintaining military deterrence, or regulating nuclear reactors. Climate change belongs in the same category. The Paris Agreement’s temperature targets were never the output of a neat optimization model. They were, appropriately, socially negotiated markers of tolerable risk.
Heightened concerns about energy security have also strengthened the case for curbing the use of oil and gas. Recent shocks, including the Strait of Hormuz crisis that sent oil and gas prices sharply higher, have reminded import-dependent economies that reliance on globally traded fuels exposed to geopolitical risks can leave them vulnerable to war, coercion, and price spikes in an increasingly fragmented world. A system that relies more on electricity from domestic sources, including renewable energy and nuclear power, will be less vulnerable to those risks.
The climate apocalypse may not be around the corner. But Europeans got a frightening reminder last week that a hotter, more unstable, and more costly world already is. The lesson of recent reassessments in climate science and economics is not that climate risk was invented or that the case for action has weakened. What has changed is that the best-case outcomes are slipping out of reach, while the full scale of the damages from continued warming remains deeply uncertain. That combination strengthens the case for rapid climate action rather than weakens it.
