The Trump EPA wants to eliminate protections against the climate pollution that endangers public health. The public must be allowed to weigh in.

The Trump EPA recently made the deeply damaging decision to repeal the Endangerment Finding — the foundational scientific determination that climate change harms public health and welfare. To justify that decision, it relied on new and deeply flawed analysis that the American public never got a fair chance to examine.  

Environmental Defense Fund led a group of 16 environmental and public health groups in filing a petition that calls on EPA to reopen its decision and let people comment on the new material. This is a core rule of fair decision-making, and it is especially important now, as the Trump administration races ahead to abandon scientific consensus and repeal a decade-and-a-half of protective standards.  

The Endangerment Finding supports commonsense safeguards to cut pollution, protect health, and save money 

The Endangerment Finding is EPA’s bedrock protection against the climate pollution that endangers people’s health and well-being. It’s also the legal basis for limits on climate pollution from cars and trucks. The Trump EPA’s
repeal attempts to remove this bedrock finding along with all federal limits on vehicle climate pollution.  

EDF, along with hundreds of thousands of concerned stakeholders — individuals, business representatives, state and local officials, and public health and medical associations — filed public comments opposing this unlawful rollback, and we have done extensive analysis that shows the enormous stakes for Americans.  

Repealing these climate protections could: 

• Add as much as 18 billion tons of additional climate pollution to our air through 2055
• Impose as much as $4.2 trillion in climate damages and up to $500 billion more in health costs from increased soot and smog-forming pollution
• Cause up to 58,000 premature deaths. That’s early, preventable mortality for a population that could be a mid-sized town

All those damages are on top of $1.4 trillion in additional fuel costs — a cost estimate that was based on cheaper gas prices, predating the current high prices at the pump.  

(See EDF’s new interactive maps for more about how climate change is already raising costs for families and how the administration’s attack on the Endangerment Finding will make that worse.)

Totally new and flawed analysis  

The Clean Air Act requires EPA to disclose the factual basis and methodology for a proposed rule so the public has a real chance to respond. However, EPA is attempting to repeal these foundational protections based on totally new and flawed analysis that did not exist at the time of the public comment period — so no member of the public could ever critique it.   

The biggest problem involves EPA’s new so-called “futility” analysis, which claims that the agency can’t regulate climate pollution from cars and trucks because their impacts on health and welfare are so small as to be meaningless. This is particularly cynical given that the U.S. transportation sector is the largest source of climate pollution in the U.S. and one of the largest sources in the world. 

In its earlier proposal for the repeal, EPA leaned heavily on a draft Climate Working Group report to justify this conclusion — a report written by a small group of handpicked climate skeptics that was inconsistent with overwhelming scientific evidence. Following a lawsuit brought by EDF and the Union of Concerned Scientists, a federal court found that draft was secretly created in violation of federal sunshine laws.  

In its final rule, EPA said it was no longer relying on that report. Instead it switched to a completely new and different technical approach — modeling claiming to show how U.S. vehicle carbon dioxide emissions impact global temperature and sea level rise. That analysis was never put before the public for comment, and it’s wrong — slanted in countless ways that make the impacts look artificially small.  

For instance, EPA begins its modeling in 2027, after more than fifteen years of greenhouse gas protections have already reduced pollution and delivered cleaner technology into the vehicle market. It’s like examining a patient after medicine has lowered a fever and saying the medicine must have been pointless because the temperature is lower now. EPA’s choice of starting point takes credit for years of pollution protections and then uses that already-improved baseline to claim the pollution protections do not matter. 

EPA also chooses to focus on only two climate indicators — global average temperature and global sea level rise. EPA itself admits these numbers “are not themselves the adverse impacts on health and welfare.” They are middle steps, not the final harm people actually experience.  

EPA then takes its artificially small temperature and sea level impacts and just divides them in half to make them look even smaller. EPA admits that its method “pairs some analytic tools not intended for this purpose with other tools in the literature” and “cannot be assumed to translate with precision directly to specific adverse health or welfare impacts.” In other words, EPA admits it used a method not intended for this purpose and the results do not represent what the agency claims.

EPA goes on to compare its slanted calculations of temperature and sea level impacts to three yardsticks  against  which it claims climate pollution does not measure up:  

• The degree of uncertainty in our ability to measure global temperature and sea level changes, or “measurability”  
• How much global temperature varies over time, or “variability”  
• A one-percent contribution to the total pollution problem 

According to EPA, if its modeled temperature and sea level changes fall below these yardsticks, then they’re so small as to be meaningless. But these are the wrong yardsticks — and the wrong conclusions. 

To begin with, the agency uses measurability and variability even though those metrics do not speak to the impacts that result from reducing climate pollution from cars and trucks. For example, say the average global temperature in 2030 is 60 degrees plus or minus two degrees, for a temperature band of 58-to-62 degrees. If we reduce temperatures by one degree, that would reduce the average temperature to 59 degrees, and the entire temperature band to 57-to-61 degrees. The whole world would be one degree cooler, a meaningful change.  

In addition, EPA doesn’t explain how it derived its measurability and variability figures. In one case, it doesn’t reveal the figure at all. The government websites EPA cites do not contain the agency’s numbers, and in trying to reconstruct EPA’s work we found numerus math errors which, when corrected, produce figures as much as 85% lower. This is an especially serious problem when those flawed numbers are so central to EPA’s conclusions in the final rule. 

When we apply more rigorous methods to estimate both the impacts and the thresholds for measurability and variability, we find that the impacts far exceed these thresholds. Our modeling shows that U.S. cars and trucks produce so much climate pollution that they could

cause sea level rise almost 36 times the size of measurement uncertainty. They could also cause temperature impacts 24times the size of measurement uncertainty and almost 14 times the size of variability (all through 2200).  

EPA’s one percent threshold is even more revealing. EPA suggests that if an impact is around one percent of total projected global warming or sea level rise it is too small to count. The agency tries to justify this based on a string of court cases, only one of which talks about a one percent threshold but does so in an entirely different context. But context matters. One percent of a problem as vast as climate change is not a rounding error — it translates into real illnesses, real deaths, real dollars.  

Overwhelming scientific evidence supports the imperative for climate action and highlights that every single ton of climate pollution matters for protecting human health and welfare. In this case, when we assess the climate pollution harms from U.S. cars and trucks through 2200, they range up to $52.5 trillion in damages – almost twice the Gross Domestic Product (GDP) of the entire American economy in 2024.  

Another major problem is EPA’s decision to treat public health benefits from reducing deadly soot and smog as worth zero dollars. For decades, the agency has assigned dollar values to the health benefits of reducing these pollutants that worsen asthma, trigger heart and lung disease, and cause premature deaths. These monetized benefits are supported by robust scientific assessments developed across decades of empirical research and countless studies. EPA offers no new science to support its deeply damaging conclusion to assign no value to the tremendous health benefits of reducing soot and smog pollution.  

EPA is trying to support its sweeping rollback of climate and public health protections with deeply flawed analysis, without giving the public a chance to vet the agency’s work. Our petition argues that the agency must follow the law by allowing the public to see and respond to EPA’s choices before EPA locks them into place.  

Read more:  

Petition  
Accompanying technical appendices 
Erratum 
Press release 

You can also read more about the lawsuit challenging EPA’s repeal of its Endangerment Finding. This petition for administrative reconsideration is separate from and in addition to that lawsuit.