MADISON | Wisconsin’s Green Fire (WGF), a science-based conservation nonprofit, urges the US Environmental Protection Agency (EPA) to keep the 2009 Endangerment Finding in place and to maintain the greenhouse gas emission standards for light-duty, medium-duty, and heavy-duty vehicles and engines. WGF is submitting detailed comments opposing the EPA’s proposed rule (Federal Register Number 2025-14572). WGF’s comments were prepared by subject matter experts on climate change and are available on the WGF website here. The EPA’s public comment period on this topic closes on September 22nd, 2025.
In a 2007 US Supreme Court decision, the nation’s highest court ruled that greenhouse gases qualified as air pollutants under the Clean Air Act. The US EPA subsequently issued the 2009 Endangerment Finding. It stated that: 1) that greenhouse gases threaten public health and 2) that motor vehicles contribute to greenhouse gas pollution. These findings are the basis for emissions standards that aim to reduce pollution and protect public health. There have been no new developments, particularly no peer-reviewed scientific studies, that cast doubt on the reliability of the 2009 Endangerment Finding or challenge its assumptions. Counter to the EPA’s mission to protect human health and the environment, the EPA is ignoring or misconstruing the science and the obvious facts: climate change is a grave existential threat to human health and welfare.
We now have nearly 15 years of additional experience and data to support the Endangerment Finding more thoroughly and with greater confidence. According to the National Oceanic and Atmospheric Administration (NOAA), the past 10 years have been the 10 warmest years on record since 1850. Additionally, nine of the top 10 years for extreme one-day precipitation events have occurred since 1995. This is not a random coincidence.
These changes impact Wisconsin directly, too. According to the 2021 Assessment Report from the Wisconsin Initiative on Climate Change Impacts (WICCI), “In the last decade, nearly every region of our state has experienced extreme rainfall events that led to flooding of roads, homes, businesses, and farm fields.” The August 2025 flooding in Milwaukee and other parts of southeastern Wisconsin is just one example of a 1000-year rainstorm. From 1980 to 2024, NOAA documented 44 severe storms in the Midwest, including Wisconsin. In a similar time frame from 1988 to 2023, there were nine droughts. Droughts are associated with health risks like heat stress. Furthermore, droughts can cause widespread crop losses to economically important crops like corn and soybeans. Life-threatening weather events are becoming almost annual in our region.
Beyond weather events, greenhouse gases endanger public health by lowering the air quality. Emissions from vehicles and other sources create smog. Warm temperatures accelerate those smog-creating conditions. Smog harms human health, resulting in acute respiratory symptoms that lead to reduced productivity (missed school and work days), hospitalizations, and premature death.
Warming temperatures and changing weather patterns also bring increased risks of vector-borne disease like Lyme disease, West Nile virus, dengue fever, and Zika virus. According to BioMed Research International, since 2009, cases of dengue have been documented in Florida for the first time in 75 years. The warmer and wetter conditions caused by global warming will make some areas of the US more conducive to the spread of mosquitoes and ticks that spread these dangerous diseases.
The climate factors occurring today, including temperature increases, changing precipitation patterns, changes in humidity and other factors are different in one dramatic and devastating regard—the rapid rate of change. Thousands of species of birds, fish, mammals, amphibians, trees, coral reef species, and others are threatened with extinction. In 2020, the International Union for Conservation of Nature (IUCN) assessed that climate change was the biggest factor leading to extinction.
Page 36292 of the Federal Register entry (Vol. 90, No. 146 / Friday, August 1, 2025) describes the various documents, reports, proceedings, and other materials reviewed and considered by the EPA Administrator (Mr. Zeldin) in pursuing this rulemaking to rescind the Endangerment Finding. The first document listed on that page was a report from the Department of Energy (DOE) entitled “A Critical Review of Impacts of Greenhouse Gas Emissions on the U.S. Climate.” As published in ScienceAdvisor, Science Feedback, and elsewhere, many scientists referenced in this report have quickly denounced the report for cherry-picking data, mischaracterizing findings, and sometimes coming to the opposite conclusion their research papers actually support.
Wisconsin Green Fire does climate work because we care deeply about what kind of future we’re leaving for our children and grandchildren. Concerned members of the public can submit their comments to the Federal Register under Docket ID No. EPA-HQ-OAR-2025-0194 by September 22, 2025 or contact their elected representatives about the Endangerment Finding.
