US Environmental Protection Agency Administrator Lee Zeldin speaks at EPA Headquarters on February 18, 2025, in Washington, DC. (Photo by Kayla Bartkowski/Getty Images)
Repealing the endangerment finding, they wrote, “is contrary to science and the public interest.”
More than 1,000 scientists and other experts on Tuesday sent a letter to US Environmental Protection Agency Administrator Lee Zeldin explaining why they “strenuously object” to his effort to repeal the EPA’s 2009 “endangerment finding,” which has enabled federal climate regulations over the past 15 years.
Amid mounting fears that he would take such action, Zeldin in late July unveiled the rule to rescind the landmark legal opinion that greenhouse gases endanger public health and the welfare of the American people—part of Republican President Donald Trump’s broader pro-polluter agenda.
“As climate scientists, public health experts, and economists, we can attest to the indisputable scientific evidence of human-caused climate change, its harmful impacts on people’s health and well-being, and the devastating costs it is imposing on communities across the nation and around the world,” states the new letter, organized by the Union of Concerned Scientists. “This explicit attempt to undermine or weaken these findings, as well as the critical regulations linked to them, is contrary to science and the public interest.”
“We also strongly oppose the EPA’s reckless dismissal of established climate science as part of its proposal to repeal the endangerment finding, including the agency’s heavy reliance on an unscientific study commissioned by the Department of Energy. This report is rife with inaccuracies, deliberately cherry-picks and mischaracterizes data, and has not undergone a rigorous scientific review process,” the letter continues, echoing an expert review of the government report from earlier this month.
🚨NEW: Scientists from nearly every state, DC, and Puerto Rico are calling out Trump's Environmental Protection Agency for failing to fulfill their core duties: protect the environment and public health.
Citing major US and global analyses, along with thousands of independent, peer-reviewed scientific studies, the letter stresses that “the scientific evidence on human-caused climate change and its consequences was unequivocal in 2009 and, since that time, has become even more dire and compelling.”
It says that “based on the best available science,” scientists know:
Climate change poses severe harms to human health and well-being;
Climate change is clearly increasing the likelihood of extreme events; and
The economic toll of climate change is rising.
Harms to human health and well-being include higher rates of heat-related deaths, increased spread of some infectious diseases, and decreased food and water safety due to climate-fueled extreme weather events, the letter says. It also highlights that, according to data from the National Oceanic and Atmospheric Administration (NOAA), “billion-dollar disasters in the United States are on the rise, driven by a combination of climate factors and increased development in disaster-prone areas.”
Despite such findings, the Trump administration is making various moves to boost the planet-wrecking fossil fuel industry and the president withdrew the United States from the Paris Agreement—again—when he returned to office in January. Parties to the 2015 climate agreement aim to limit global temperature rise this century to 1.5°C above preindustrial levels.
🌎🧪Over 1,000+ scientists joined together to defend the EPA's Endangerment Finding, and you have SIX DAYS to make your voice heard too.
“The world stands on the cusp of breaching the 1.5°C (2.7°F) mark on a long-term basis, the global average temperature increase above preindustrial levels that scientists have long warned about,” the experts noted Tuesday. “Communities across the nation are already dealing with devastating and costly climate impacts, that are set to worsen as global warming accelerates. Humanity’s window to act to stave off some of the worst impacts of climate change is fast closing; any further delay is harmful and costly.”
“We urge you to stop dismantling critical climate regulations and evading EPA’s responsibility by pushing disinformation about climate science and impacts,” they concluded. “Instead, we call on you to act with urgency to help address this pressing challenge by limiting heat-trapping emissions. People across the nation are relying on the EPA to fulfill its mission to protect public health and the environment.”
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Climate activists protest against US President Donald Trump’s state visit to Britain outside Windsor Castle, September 15, 2025 [Pic: Richard Bayfield]
‘A stain on our collective consciousness’
CLIMATE activists unfurled a banner calling US President Donald Trump a war criminal in the grounds of Windsor Castle ahead of a series of protests during his three-day state visit to Britain starting on Tuesday.
The sign showed a picture of President Trump with the words “Climate criminal. War criminal. The only place he’s welcome is The Hague.”
Campaigners from Fossil Free London chanted: “Climate criminal, war criminal, Trump’s not welcome here” as they drew attention to the “wannabe dictator’s” climate and foreign policy record today.
His second state visit to Britain has sparked calls for a large demonstration in London tomorrow, 2pm at Portland Place, organised by the Stop Trump Coalition.
Fossil Free London director Robin Wells said: “Genocide is unfolding. Seen on our phones through the faces of thousands of screaming children. Floods and fires across Europe get closer each day to our own front doors. But Trump claps and cheers for more.
Elon Musk urges you to be a Fascist like him, says that you can ignore facts and reality then.Donald Trump urges you to be a Climate Science denier like him. He says that he makes millions and millions for destroying the planet, Burn, Baby, Burn and Flood, Baby, Flood.
A child pours tap water into a glass in this undated photo. (Photo by Teresa Short/Getty Images)
One environmental attorney said that the EPA proposal “prioritizes chemical industry profits and utility companies’ bottom line over the health of children and families across the country.”
Public health and environment defenders on Friday condemned the Trump administration’s announcement that it will no longer uphold Environmental Protection Agency rules that protect people from unsafe levels of so-called ”forever chemicals” in the nation’s drinking water.
In addition to no longer defending rules meant to protect people from dangerous quantities of per- and polyfluoroalkyl substances (PFAS)—called forever chemicals because they do not biodegrade and accumulate in the human body—the EPA is asking a federal court to toss out current limits that protect drinking water from four types of PFAS: PFNA, PFHxS, GenX, and PFBS.
The EPA first announced its intent to roll back limits on the four chemicals in May, while vowing to retain maximum limits for two other types of PFAS. The agency said the move is meant to “provide regulatory flexibility and holistically address these contaminants in drinking water.”
However, critics accuse the EPA and Administrator Lee Zeldin—a former Republican congressman from New York with an abysmal 14% lifetime rating from the League of Conservation Voters—of trying to circumvent the Safe Drinking Water Act’s robust anti-backsliding provision, which bars the EPA from rolling back any established drinking water standard.
“In essence, EPA is asking the court to do what EPA itself is not allowed to do,” Earthjustice said in a statement.
“Administrator Zeldin promised to protect the American people from PFAS-contaminated drinking water, but he’s doing the opposite,”Earthjustice attorney Katherine O’Brien alleged. “Zeldin’s plan to delay and roll back the first national limits on these forever chemicals prioritizes chemical industry profits and utility companies’ bottom line over the health of children and families across the country.”
Jared Thompson, a senior attorney with the Natural Resources Defense Council (NRDC), said that “the EPA’s request to jettison rules intended to keep drinking water safe from toxic PFAS forever chemicals is an attempted end run around the protections that Congress placed in the Safe Drinking Water Act.”
“It is also alarming, given what we know about the health harms caused by exposure to these chemicals,” Thompson added. “No one wants to drink PFAS. We will continue to defend these commonsense, lawfully enacted standards in court.”
PFAS have myriad uses, from nonstick cookware to waterproof clothing to firefighting foam. Increasing use of forever chemicals has resulted in the detection of PFAS in the blood of nearly every person in the United States and around the world.
Approximately half of the U.S. population is drinking PFAS-contaminated water, “including as many as 105 million whose water violates the new standards,” according to the NRDC, which added that “the EPA has known for decades that PFAS endangers human health, including kidney and testicular cancer, liver damage, and harm to the nervous and reproductive systems.”
Betsy Southerland, a former director of the Office of Science and Technology in the EPA’s Office of Water, said in a statement Friday:
The impact of these chemicals is clear. We know that this is significant for pregnant women who are drinking water contaminated with PFAS, because it can cause low birth weight in children. We know children have developmental effects from being exposed to it. We know there’s an increased incidence of cardiovascular disease and cancer with these chemicals.
Two of the four chemicals targeted in this motion are the ones that we expect to be the most prevalent, and only increasing contamination in the future. With this rollback, those standards would be gone.
Responding to Thursday’s developments, Environmental Advocates NY director of clean water Rob Hayes said that “the EPA’s announcement is a big win for corporate polluters and an enormous loss for New York families.”
“Administrator Zeldin wants to strip clean water protections away from millions of New Yorkers, leaving them at risk of exposure to toxic PFAS chemicals every time they turn on the tap,” he added. “New Yorkers will pay the price of this disastrous plan through medical bills—and deaths—tied to kidney cancer, thyroid disease, and other harmful illnesses linked to PFAS.”
While Trump administration officials including Agriculture Secretary Brooke Rollins and Health and Human Services Secretary Robert F. Kennedy Jr. have claimed they want to “make America healthy again” by ending PFAS use, the EPA is apparently moving in the opposite direction. Between April and June of this year, the agency sought approval of four new pesticides considered PFAS under a definition backed by experts.
“What we’re seeing right now is the new generation of pesticides, and it’s genuinely frightening,” Nathan Donley, the environmental health science director at the Center for Biological Diversity, toldCivil Eats earlier this week. “At a time when most industries are transitioning away from PFAS, the pesticide industry is doubling down. They’re firmly in the business of selling PFAS.”
Elon Musk urges you to be a Fascist like him, says that you can ignore facts and reality then.Donald Trump urges you to be a Climate Science denier like him. He says that he makes millions and millions for destroying the planet, Burn, Baby, Burn and Flood, Baby, Flood.
The price of eggs has more than doubled in the past eight years, which isn’t great, but at least you can eat eggs. The price of US government subsidies for the fossil-fuel industry has also more than doubled in that time, which is far, far less great. Welfare for an industry that makes billions of dollars in profits and pollutes the climate is worse than useless. It’s self-destructive.
The federal government gives oil, gas and coal producers at least $34.8 billion in subsidies each year, according to a new study by the research and advocacy nonprofit Oil Change International. In 2017, OCI estimated these gifts at $14.7 billion annually. This doubling in federal largesse has taken place under both Democratic and Republican political administrations, highlighting the difficulty of stopping its growth, much less reversing it.
In fact, some of the most recent extensions of federal aid have made it possible for these subsidies to explode in the future, threatening to reach trillions of dollars. When the world needs exponential growth in clean-energy investments to avoid the most catastrophic effects of global heating, the US government will be bankrolling fossil-fuel expansion and stoking the emergency.
Donald Trump urges you to be a Climate Science denier like him. He says that he makes millions and millions for destroying the planet, Burn, Baby, Burn and Flood, Baby, Flood.Greenpeace activists display a billboard during a protest outside Shell headquarters on July 27, 2023 in London. (Photo: Handout/Chris J. Ratcliffe for Greenpeace via Getty Images)Experienced climbers scale a rock face near the historic Dumbarton castle in Glasgow, releasing a banner that reads “Climate on a Cliff Edge.” One activist, dressed as a globe, symbolically looms near the edge, while another plays the bagpipes on the shores below. | Photo courtesy of Extinction Rebellion and Mark Richards
Global warming linked to the world’s biggest oil and gas companies made all “major” 21st century heatwaves more intense and frequent.
This is according to new research, published in Nature, which uses “extreme event attribution” to assess the impact of climate change on all 21st-century heatwaves that were classified as “major disasters”.
The authors find one-quarter of the 213 heatwaves would have been “virtually impossible” without human-caused global warming.
They add that the effect of climate change on heatwave frequency and intensity is becoming more pronounced as the planet warms.
The study estimates the emissions stemming from the operations and production of more than 100 “carbon majors”, such as ExxonMobil, BP, Saudi Aramco and Shell.
The fossil fuels produced by these companies account for 60% of all human-caused CO2 emissions over 1850-2023, the study says.
The authors find that heatwaves recorded over 2000-23 were made, on average, 1.7C hotter due to climate change, with half of this increase due to the emissions originating from carbon majors.
This study “could be used to support future climate lawsuits and aid diplomatic negotiation”, according to a scientist not involved in the research.
The EM-DAT database catalogues all “major disasters” that have been reported since the year 1900 – defined as events that cause at least 10 fatalities, affect at least 100 people, or result in the declaration of state of emergency or a call for international assistance.
Between 2000 and 2023, the database lists more than 200 heatwaves. These are shown on the map below, where darker pink indicates a greater number of heatwaves. Countries with no reported heatwaves are shown in grey.
The map below shows the number of heatwaves per country recorded over 2000-23 on the EM-DAT database. Data: Quilcaille et al (2025).
The study authors acknowledge that heatwave reporting is “highly uneven”, with only nine of the heatwaves reported in the database since the year 2000 in Africa, Latin America or the Caribbean. (This is largely because extreme heat events in these regions are not routinely monitored.)
They then carried an attribution analysis on each heatwave to identify whether it was made more likely or intense due to human-caused climate change.
The chart below shows how climate changes increased the intensity and frequency of the 78 heatwaves assessed over 2000-09 (left), 54 heatwaves assessed over 2010-19 (middle) and 81 heatwaves assessed over 2020-23 (right).
The authors find that climate change increased the intensity and probability of all 213 heatwaves in the study. They add that the influence of climate change on heatwaves is strengthening over time.
In each panel, the bars show the percentage of heatwaves in that time period that were made 0.25-1.0C (yellow), 1.0-2.0C (orange) or 2.0-3.0C (red) hotter due to climate change.
The position of bars indicate the change in likelihood of the heatwaves. This ranges from those made 1-10 times more likely due to climate change (left-most bar in each panel) to those made more than 11,000 times more likely (right-most bar in each panel).
The extent to which climate changes increased the intensity and frequency of the 78 heatwaves assessed over 2000-09 (left), 54 heatwaves assessed over 2010-19 (middle) and 81 heatwaves assessed over 2020-23 (right). These are shown by colours and bar heights respectively. Source: Quilcaille et al (2025).
Heatwaves recorded over 2000-09 were, on average, 20 times more likely due to climate change, according to the authors. Meanwhile, those recorded over 2010-19 were about 200 times more likely.
Similarly, 2000-09 heatwaves were 1.4C hotter due to human-caused climate change on average, according to the study, while 2010-19 heatwaves were made 1.7C hotter.
The study finds that human-caused climate change made 55 heatwaves at least 10,000 times more likely. According to the authors, this is “equivalent to saying that they would have been virtually impossible” without the influence of human activity.
Carbon majors
To assess the contribution to heatwaves by oil and gas companies’ products, the authors use a database of carbon dioxide and methane emissions from 180 carbon majors over 1854-2023. This includes direct emissions from the companies, as well as the emissions released when the oil and gas they produced is used by others.
The 180 carbon majors in the database represent 60% of all human-caused CO2 emissions, including land use, over 1850-2023, according to the study. The paper adds that 14 companies, including ExxonMobil, BP, Saudi Aramco and Shell, are responsible for almost half of these emissions.
Using the Earth system model OSCAR, the authors estimate that global average surface temperatures increased by 1.3C between the 1850-1900 average and the year 2023.
They find that 0.7C of this increase was linked to the carbon majors, with 0.3C due to the emissions of the 14 largest.
The chart below, taken from an accompanying Nature “news and views” article, shows the contribution of oil and gas companies’ products to increasing global average surface temperatures over 1950-2023, compared to the 1850-1900 average.
Each colour indicates a carbon major, while grey indicates other sources of temperature increase, such as land-use change.
The contribution of oil and gas companies to increasing global average surface temperatures over 1950-2023, compared to the 1850-1900 average. Each colour indicates a company, while grey indicates other sources of temperature increase. Source: Haustein (2025).
Heatwaves recorded over 2000-23 were, on average, 1.7C hotter due to climate change, according to the study. The authors find that emissions originating from carbon majors and their products contributed about half of the increase in intensity of heatwaves seen since pre-industrial times.
The authors then break down the contribution of emissions from each carbon major on each heatwave in their analysis.
For example, they find that the emissions linked to Saudi Aramco made 51 heatwaves at least 10,000 times more likely. They add that on average, emissions tied to the company made the 213 heatwaves 0.04C hotter.
Legal action
Attribution studies already play an important role in courts by providing evidence that helps judges to determine liability.
Dr Rupert Stuart-Smith is a research associate in climate science and the law at the University of Oxford’s Sustainable Law Programme. He was not involved in the study, but has published separate work showing that the emissions linked to each of the six largest corporate emitters cause one heat-related death in Zurich alone, every summer.
Stuart-Smith tells Carbon Brief that the new paper is a “high-quality analysis and a meaningful step forward for the field of climate change attribution”. He adds:
“With more and more lawsuits aiming to hold high-emitting companies responsible for their contributions to climate change impacts or compel state and corporate actors to reduce their emissions and prevent rising climate harms, work like this provides the basis for well-informed judicial decision-making.”
Dr Yann Quilcaille is a researcher at ETH Zürich and lead author of the study. He stresses the importance of attribution research for court cases, telling Carbon Brief that he hopes his work “can be used by legal practitioners”.
However, he also says that his role as a scientist is not to assign “responsibility” for climate change, but to “provide information to governments for decision making and to courts for litigation”.
Mankin tells Carbon Brief that the new paper is “very closely” linked to his research.
Callahan says the new paper is “an important contribution to an emerging literature that illustrates how individual emitters can be linked to the change risk of extreme climate conditions and human impacts”.
He explains that “this kind of evidence will be important in courtrooms – holding emitters legally accountable requires demonstrating a causal nexus between that emitter and a particularised harm suffered by a plaintiff”.
Attribution
The cutting-edge field of extreme weather attribution seeks to establish the role that human-caused warming played in these events. Attribution studies have been carried out on hundreds of heatwaves all around the world, as shown in Carbon Brief’s interactive map.
The new paper uses one of the earliest and most commonly used methods of attribution, called “probabilistic attribution”.
The authors first chose a temperature “threshold” to define their heatwave.
They then used a global climate model to simulate two worlds – one mirroring the world as it was during the heatwave and the other using the climate of 1850-1900. This second scenario is used to represent the climate in a world without human-caused climate change.
The authors run their models thousands of times in each scenario. As the world’s climate is inherently chaotic, each model “run” – individual simulations of how the climate progresses over many years – produces a slightly different progression of temperatures. This means that some runs simulate the heatwave, while others do not.
The authors count how many times the threshold temperature was in each model run. They then compared the likelihood of crossing the threshold temperature in the world with – and a world without – climate change.
For example, they find that the 2021 Pacific north-west heatwave was made 3.1C hotter due to human caused climate change and more than 10,000 times more likely.
(A study by the WWA at the time of the heatwave found that the heatwave was made 150 times more likely. The discrepancy is due to differences in the definition of the event, as well as its “very unlikely nature” according to the study authors.)
Dr Frederieke Otto is a professor at Imperial College London and founder of the WWA initiative. She tells Carbon Brief that the new study is “very similar to some other recent studies on impacts, based on the hazard attribution method used by WWA”, but says that “this is the most high profile and wide-reaching one”.
Otto adds:
“I do hope that many more impact attribution studies will follow, based on our or other extreme event attribution studies. We need more research on this.”
Donald Trump urges you to be a Climate Science denier like him. He says that he makes millions and millions for destroying the planet, Burn, Baby, Burn and Flood, Baby, Flood.Nigel Farage urges you to ignore facts and reality and be a climate science denier like him. He says that Reform UK has received millions and millions from the fossil fuel industry to promote climate denial and destroy the planet.Greenpeace activists display a billboard during a protest outside Shell headquarters on July 27, 2023 in London. (Photo: Handout/Chris J. Ratcliffe for Greenpeace via Getty Images)Experienced climbers scale a rock face near the historic Dumbarton castle in Glasgow, releasing a banner that reads “Climate on a Cliff Edge.” One activist, dressed as a globe, symbolically looms near the edge, while another plays the bagpipes on the shores below. | Photo courtesy of Extinction Rebellion and Mark Richards
Climate activists protest against US President Donald Trump’s state visit to Britain outside Windsor Castle, September 15, 2025 [Pic: Richard Bayfield]
