Hill Heat

In a lawsuit filed Monday, the university coalition that manages the National Center for Atmospheric Research (NCAR), in Boulder, Colo., defended it against the Trump regime’s planned breakup. The University Corporation for Atmospheric Research (UCAR) accused the Trump White House of using the National Science Foundation (NSF) to inflict “unlawful retaliation” against the Colorado state government.

The suit cites the ongoing case Colorado v. Trump, over the Trump administration’s blockage of SNAP food benefits for the state. The judge in that case agreed the Trump regime’s administrative actions against Colorado are tied to Trump’s efforts to overturn Colorado’s conviction of county clerk Tina Peters, who conspired to overturn the 2020 election.

The lawsuit, filed by the boutique California litigation firm Hueston Hennigan on behalf of UCAR, notes a “cascading series of retaliatory measures” against UCAR and NCAR in addition to NSF’s plans to disintegrate NCAR:

Since then, the Agencies have taken concrete retaliatory actions targeting UCAR and NCAR across multiple fronts. The cascading series of retaliatory measures has included:

• NSF’s decision to divest UCAR of its stewardship of the NCARWyoming Supercomputing Center (“NWSC”) that UCAR built, financed with tax-exempt bonds, and has operated since 2012;
• NOAA’s termination of a multi-million-dollar cooperative agreement with UCAR designed to fund climate adaptation and mitigation research;
• NSF’s use of disparate and undue reporting requirements calculated to saddle UCAR and NCAR with pointless bureaucratic burdens; and
• NSF’s imposition of gag orders that unconstitutionally restrain the speech of UCAR and NCAR officials to prevent them from communicating with the public and their employees.

The defendants named for their “series of ongoing unconstitutional, arbitrary, and capricious actions” are the National Science Foundation, NSF director Brian Stone, the National Oceanic and Atmospheric Administration, NOAA director Neil Jacobs, the White House Office of Management and Budget, and OMB director Russ Vought.

In 2011, climate scientist Kevin Trenberth wrote one of the most important scientific papers on climate change in history. Its lessons remain unlearned.

In “Attribution of climate variations and trends to human influences and natural variability,” published in WIREs Climate Change in 2011, NCAR climatologist Kevin Trenberth shattered the lie implicit in almost all scientific communication, policymaking, and journalistic coverage of climate change and its causal relationship with extreme weather.

As the abstract explains in scientific terms:

Past attribution studies of climate change have assumed a null hypothesis of no role of human activities. The challenge, then, is to prove that there is an anthropogenic component. I argue that because global warming is ‘‘unequivocal’’ and ‘very likely’ caused by human activities, the reverse should now be the case. The task, then, could be to prove there is no anthropogenic component to a particular observed change in climate, although a more useful task is to determine what it is. In Bayesian statistics, this change might be thought of as adding a ‘prior’. The benefit of doubt and uncertainties about observations and models are then switched. Moreover, the science community is much too conservative on this issue and too many authors make what are called ‘Type II errors’ whereby they erroneously accept the null hypothesis. Global warming is contributing to a changing incidence of extreme weather because the environment in which all storms form has changed from human activities.

Trenberth’s article precisely described the phenomenon identified in climate science communication at the time by writers like myself. In a 2010 article entitled “If Doctors Were Climate Scientists, We’d Be Dead,” I listed several examples of climate journalism and quotations from climate scientists privileging the false null hypothesis:

“it is impossible to blame mankind for single severe weather events”

“language — which suggests that we can, in fact, attribute specific weather events to global warming — should be strictly avoided”

“the usual caveat that no current weather event can be said to be ‘caused’ by climate change”

“As we continually stress, one extreme weather event, or even a series of weather events, is not caused by global warming or climate change”

“you cannot say a single event or a single summer is unequivocally due to climate change — by definition it’s weather, and not climate”

“a single weather event cannot be blamed on climate change”

“climate change cannot be said to cause an individual event”

“You can’t attribute any single weather-related event to a hotter planet”

This seeding of false doubt continues to this day, to the benefit of no one but the polluters profiting from our inaction.

“The result of bad and misleading statements about attribution, of which there have been many, is to grossly underestimate the role of humans in climate events of note in recent times to the detriment of perceptions about climate change and subsequent policy debates,” Trenberth wrote in 2011. “Humans are changing our climate. There is no doubt whatsoever.”

We have exactly one planet to live on, and it’s one whose climate system is now being driven by manmade pollution. The coming changes which are known with absolute certainty — sea level rise, glacial decline, ocean acidification — presage suffering on an apocalyptic scale. There is no alternate planet with everything the same except with pre-industrial levels of carbon dioxide to compare against. Weather phenomena are determined through physical processes by the state of the ocean-atmosphere system, making greenhouse pollution one of the causative agents of today’s weather.

The following was submitted by pre-eminent climate scientist Kevin Trenberth, who was employed by the National Center for Atmospheric Research from 1984 to 2019, to the National Science Foundation.

Comment on Dear Colleague Letter on the National Center for Atmospheric Research

This letter focusses on the second topic, “NCAR weather modeling and atmospheric observing capabilities.”

I am writing as an individual who is a U.S. citizen (and also a New Zealand citizen). I lived in the United States for over 45 years and was employed by NCAR until 2019. Earlier, for 7 years from 1977 to 1984, as a professor at the University of Illinois, I visited NCAR every summer and had my students using the NCAR computers and data archives remotely.

I believe my credentials are second to none as a climate scientist:

My publication record includes a total (as of January 2026) of 80 books or book chapters, and 308 journal articles, plus 26 non-technical articles on The Conversation and 22 on New Zealand’s Newsroom, for a total of 662 publications plus 4 videos. On Google Scholar, there are > 137,500 citations and an H index of 142 (or 89 since 2021). I have been heavily involved in the World Climate Research Programme.

I am appalled at the attacks on NCAR and attempts to break it up. That is not to say that its operations could not be improved, but much of the U.S. Administration’s rhetoric is misguided and scientifically quite wrong.

NCAR is a national and even international center for research on the atmosphere and Earth system. It plays a major role as a center for 125 or so universities in education of students and provides facilities for research. Many students visit over the summer and participate in specially designed programs and seminars, and many doctoral theses are written jointly with NCAR scientists as co-advisors. Altering NCAR would be a major setback for the entire community, and it would also ultimately negatively impact every person in the U.S. and on Earth, and the impact would be felt for decades to come. NCAR activities include maintaining a major community super-computing center along with enormous data archives; heavily instrumented airplanes and many other instruments for field programs and exploring the Sun, and maintaining and developing community weather and Earth system models that are used widely in the US and around the world. The latter range from specialized models, such as for FAA and aircraft and airport management, a hydrology model, a major weather model (Weather Research and Forecasting Model: WRF), and the Community Earth System Model. The CESM has evolved from being a climate model to much more. A key aspect of all of these is that the atmosphere is global and it interacts with the land and oceans, and solar radiation. The land includes all of the complexity of the topography and vegetation, as well as ice and snow cover. Accordingly, it is an exceedingly challenging problem and through NCAR the entire community can participate fully.

NCAR’s science is diverse, and involves all aspects of atmospheric sciences, including atmospheric chemistry, and also the upper atmosphere and the Sun. It increasingly goes further to embrace all Earth sciences, including the entire climate system (atmosphere, oceans, land and ice), and social science aspects on how to best utilize this information for societal benefit. Climate change is a tiny component of all this, but has to be included because all the Earth systems are changing, and now most of that change is driven by human activities. But even in the absence of climate change, climate study and understanding is essential for all of human endeavours, especially farming, forestry, air travel, shipping and transport.

It has been argued that NCAR should not do climate but should focus on improving weather forecasting. However, the main challenges and scope to improve weather forecasts on all time scales are by improving the way interactions of the atmosphere occur with the land hydrology, vegetation, ice, and ocean. Rainfall fundamentally involves the hydrological cycle. It includes evaporation from the surface and oceans, transport of water vapor onto land, precipitation, stream flow back to the ocean, and storage in ponds and lakes. These are inherently all climate processes.

As another critical example, in early days dealing with hurricanes was regarded as a problem for meteorologists. Now hurricanes are recognized to depend on heat and moisture from the oceans which fuel the storms and result in heavy rainfalls and potentially flooding on land. A new major review highlights the complexities and why hurricanes are inherently a climate problem.

Ma, Z., L. Cheng, S. Camargo, K.E Trenberth, I.I. Lin, G. R Foltz, D. R. Chavas, D. Zhang, E. A Ritchie, J. Fei, C. Pasquero, K. J. E. Walsh, Z. Tan, R. L. Sriver, H. Ye and L. Zhou, 2026: Interactions of tropical cyclones with global energy and water cycles. Nature Reviews Earth & Environment, doi:10.1038/s43017-026-00770-6, in press.

I am included among the mix of authors here, involving 16 different institutions, which highlights also the global nature of the scientific issues- and that leadership is moving towards China.

None of the statements from the administration nor from NSF make sense physically and would amount to a major step backwards and loss of progress in improving skill in forecasting on all time scales. The observations, data processing, assimilation, modeling, and simulations must all be strongly linked. Climate and the atmosphere are inherently global, and their simulation have necessarily always utilized the biggest and fastest super computers available.

NCAR has been a unique leader and major center in the global and coupled aspects of climate and Earth system science, as well as in training early career scientists and graduate students. No doubt some aspects of NCAR could be improved in some way, but the component links are there because they reflect the physical and biogeochemical links in the real world and the global nature of the atmosphere.

Kevin E Trenberth