Summary:
Advances in climate fingerprinting, which uses patterns of observed climate change to distinguish human influences from natural variability, have improved scientists’ understanding of how greenhouse gas emissions are altering Earth’s climate system.
A review published in Earth’s Future, led by Benjamin Santer of the University of East Anglia, examines research conducted since 2009, when the US Environmental Protection Agency (EPA) determined that greenhouse gas emissions endanger public health and welfare. The researchers conclude that the scientific basis for that decision has strengthened substantially.
Longer observational records, improved climate models and large collections of climate simulations have helped researchers detect human influence across the atmosphere and oceans. Scientists have also improved their ability to assess how human-caused warming affects the likelihood and intensity of certain extreme weather events, particularly heatwaves and heavy rainfall in some regions.
The review challenges a 2025 US Department of Energy assessment that questioned climate attribution research. Its authors argue that the assessment fails to account for decades of scientific progress and the extensive evidence connecting human activities to observed climate changes.
— Press Release —
Scientists reaffirm ‘incontrovertible’ evidence of human influence on climate
The study shows that more than three decades of climate “fingerprint” research has provided overwhelming evidence that greenhouse gas emissions are driving changes throughout Earth’s climate system.
It argues that the scientific basis for the US Environmental Protection Agency’s landmark 2009 Endangerment Finding – the legal determination that greenhouse gas emissions endanger public health in the US – was already compelling in 2009 and has become even stronger since then.
Published in the journal Earth’s Future and led by Prof Benjamin Santer at the University of East Anglia, the review traces the history of climate fingerprint studies, a field that uses patterns and timing of climate changes to distinguish between human and natural influences on Earth’s climate.
The review follows what the scientists call a “deeply flawed” July 2025 report from the US Department of Energy (DOE), which challenged the credibility of climate fingerprinting and questioned the scientific basis for the Endangerment Finding. They say the DOE assessment fails to reflect both the weight of evidence available in 2009 and significant scientific advances made over the past 17 years.
The move to revoke the Endangerment Finding has prompted concerns about the impact on human health and on efforts to reduce greenhouse gas emissions. A further concern is that rescinding it could open the door to ending other environmental regulations in the US.
Prof Santer and colleagues – from UEA, the Massachusetts Institute of Technology (MIT), Colorado State University and the University of Edinburgh – say fingerprinting techniques have evolved to the point where human influence can now be identified throughout Earth’s climate system and is “increasingly affecting the ability of societies and ecosystems to thrive”.
They note that in addition to advances in climate fingerprinting, global warming has also advanced: the post-2009 period included the 10 warmest years in instrumental surface temperature records, enhancing the signal of human-caused warming relative to the ‘noise’ of natural variability.
“The climate science that’s been published since the 2009 Endangerment Finding is now stronger than in 2009, the evidence is incontrovertible,” said Prof Santer, of UEA’s School of Environmental Sciences.
“Our review suggests that the growing body of evidence linking human activity to observed climate changes reinforces the need for policies aimed at limiting greenhouse gas emissions and addressing climate-related risks.
“A different kind of ‘Endangerment Finding’ is that the continuation of rigorous attribution science is endangered. It’s inconvenient science for those who seek a fossil fuel intensive future, because it connects the dots between fossil fuel burning and harms to our personal health, to the health of our planet, and to the health of our societies and economies.”
Over more than 30 years, Prof Santer has collaborated with colleagues around the world to identify human fingerprints in many different aspects of the climate system. His early research contributed to the historic 1995 conclusion of the Intergovernmental Panel on Climate Change: that “the balance of evidence suggests a discernible human influence on global climate.”
This new review focused on fingerprint studies that deal with annual, decadal and seasonal changes in climate. It also touched on the extensive body of scientific evidence that addresses the impact of human-caused climate change on the properties of extreme events.
Extreme events affect human and ecosystem health and welfare through such impacts as heat stress, flooding, wildfires, and crop damage. Fingerprint studies build a direct link between human-caused increases in greenhouse gases and such threats.
“Many rigorous fingerprint studies by multiple research groups worldwide have enhanced confidence in the reality and seriousness of human-caused climate change,” said Prof Susan Solomon, the Lee and Geraldine Martin Professor of Environmental Studies at MIT.
“These studies reveal that many independently monitored aspects of Earth’s climate have all been altered by global warming in physically consistent ways, just as we expect – from the top of the stratosphere to the depths of the world’s oceans.”
Prof Gabi Hegerl, of the University of Edinburgh, added: “Methods have also been developed to understand how greenhouse gases have changed the frequency and intensity of extreme events and how a weather event we observe today has been changed due to greenhouse gas emissions.”
Journal Reference:
Santer, B. D., Solomon, S., Thompson, D. W. J., Fu, Q., & Hegerl, G. C., ‘Fingerprint evidence for human effects on climate: Advances after the 2009 endangerment finding’, Earth’s Future 14, 10: e2026EF009129 (2026). DOI: 10.1029/2026EF009129
Article Source:
Press Release/Material by University of East Anglia (UEA)
Featured image credit: Jan Tang | Pexels
