Some US Scientists Stick with the IPCC Despite the Administration Pulling Out of International Climate Work

Despite a series of directives from the Trump administration aimed at disengaging the U.S. government from international climate collaboration, five U.S. scientists are part of the Intergovernmental Panel on Climate Change’s team of 100 experts from 50 countries who met in Osaka, Japan, this week to start writing a report about global warming and cities that is due in 2027.

Their participation highlights how U.S. researchers will continue to add expertise and have a voice in the international climate science community, but also how the administration’s hostility toward international collaboration will make it more difficult for U.S. scientists to engage with the global effort to study climate change.

The IPCC is resilient and can effectively perform its scientific work even if the U.S. is politically disengaged from the process, said Kevin Gurney, an atmospheric scientist at Northern Arizona University who is part of the contingent of U.S. scientists at the Osaka IPCC meeting and has worked on every IPCC assessment since the first one in 1990.

“I was a reviewer for the first report, and I still have a spiral-bound copy in my office,” he said.

As a participant since the beginning, he’s flummoxed that world leaders haven’t responded more seriously to the panel’s increasingly dire reports. 

“I never would have imagined that the year 2025 this is where we’d be,” he said. “I really thought we would take more concerted action, that the danger of climate change would resonate more with people, that surely everybody will see the urgency. But I think I was naive about politics.”

The most recent actions by the White House to obfuscate and obliterate climate science by firing federal workers, gutting agencies and censoring and deleting websites with scientific data have left his head spinning, he said.

“I was worried before I came to the meeting about whether or not I was even going to be able to come,” he said. “Obviously, as a university academic, I have freedoms that my colleagues within the U.S. science agencies don’t have. But I rely on this sort of goodwill and support that has always been there for everybody that does this.”

While travel expenses to attend meetings like the Osaka gathering are covered by the governments that send the scientists, the researchers receive no compensation for the time they work on the reports or attend meetings.

“We basically volunteer to do this,” Gurney said. “It really doesn’t cost that much other than travel to a few meetings. That’s the extent of the cost to U.S. taxpayers.”

Gurney said authors of the climate change and cities report will meet three more times in the next two years, and federal funds to pay for his travel costs are highly uncertain.

“I’m just hoping we’ll be allowed to do this, that there won’t be barriers put in the way of being involved. But I don’t know,” he said. “None of us know.”

Gurney said other U.S. scientists at the meeting in Osaka also were uncertain about what their future involvement may look like. But he anticipates being at subsequent meetings, even if the federal funding for travel is cut off. 

“For me, this process is so important that if I had to self-fund, I would,” he said.

The Trump administration did not respond to questions about future U.S. engagement with the IPCC. The executive order that ended U.S. participation says the U.S. will withdraw from “international agreements and initiatives that do not reflect our country’s values or our contributions to the pursuit of economic and environmental objectives.”

Making it Work

The IPCC is taking nominations for report authors and other roles through April 17, and one of the questions is whether NASA scientist Kate Calvin will continue to be involved as a co-chair of one of the IPCC’s three major working groups. Last week, the Trump administration fired her from her position as NASA’s chief scientist and climate advisor and it did not send her to attend an IPCC leadership meeting in late February in China. 

“I don’t know if she’s completely prohibited from participating in the IPCC,” said Kristie Ebi, a University of Washington public health researcher who worked on previous IPCC reports in a leadership role. “There are possibilities for her to continue to be engaged without traveling to meetings. During Covid, most of the IPCC meetings were remote.”

In the past, U.S. science participation in the IPCC has been organized by the federal Global Change Research Program, which coordinates climate science activities across 15 agencies and administers and supports U.S. participation in global climate efforts, as mandated by Congress in 1990. 

Ebi said the USGCRP has funded travel for U.S. scientists to attend IPCC meetings in the past, but nobody knows right now how that will work in the years ahead.

“For the rest of us, if we’re selected as authors, it’s up to us to find monies to finance our participation,” she said. “There are discussions about philanthropic organizations stepping forward and saying they’ll cover some of the travel costs, but these are all questions that we don’t have answers to at the moment.”

Usually at this stage of the IPCC process, the U.S. government would publish a federal register notice to start the selection process for the potential report authors it would nominate, but that is unlikely to happen under this administration, Ebi said. 

“It sounds like the U.S. government will not put forward nominations, but there are other ways to get nominated,” she said. “It’s more making sure that the people making nominations know which scientists would willingly volunteer their time if given the option.”

Challenging Scenarios

Participating in the IPCC will be “somewhat more challenging, but not impossible for U.S. scientists,” Ebi said. “A big feature of the IPCC are the reviews of studies in various fields, and all review comments have to be considered and responded to. I can see an effort organized by non-governmental organizations to encourage U.S. scientists to provide review comments.”

U.S. researchers could also participate as contributing chapter authors who are asked to write a paragraph or a page in their area of expertise. Chapter authors in other countries could be proactive in reaching out to U.S. scientists. 

“Both on the professional and personal level, I would say there will be quite an effort to reach out and make sure that American scientists are engaged in some way in the process,” she said. “And I suspect many scientists will want to ensure that they can provide input.”

“Having the U.S. not there binds our hands in terms of the influence on the direction of the report.”

— Kristie Ebi, University of Washington public health researcher

Scientists don’t engage with the IPCC to further their careers, she said, but “because of the importance of having these assessments for decisions about adaptation, mitigation and informing government policy.”

During the IPCC’s last assessment cycle, she said coordinating lead authors spent as long as six to nine months of unpaid time working on IPCC tasks.

“These are significant, significant amounts of time for which you’re not compensated, and people still do it,” Ebi said. “So I would expect going forward, that people are going to say, ‘Well, I’ve volunteered in the past, and I will volunteer now and find some ways to make that work.’”

It would be in the best interest of the United States to remain at the table, she said.

“One thing that has impressed me over the years in the [United Nations Framework Convention on Climate Change] is, for all of the drama, everybody shows up because you don’t want decisions taken that could affect you where you’re not at the table,” she said. “Having the U.S. not there binds our hands in terms of the influence on the direction of the report.”

Missed Opportunities

Melissa Finucane, vice president of science and innovation with the Union of Concerned Scientists, said not participating in a prestigious forum like the IPCC damages the United States’ reputation. “It makes it harder for the U.S. to lead in other international scientific initiatives,” she said. 

Early U.S. climate research, based on data from the first Earth-observing satellite missions and other sources, as well as early modeling efforts, were instrumental in building the global consensus to tackle greenhouse gas emissions and global warming. 

A diminished U.S. presence at the IPCC could result in an “economic and technical lag,” she said.

“The IPCC work informs policies that drive technological innovation, whether it’s in modeling or economic strategies,” she said. “Without access to the latest research or policy recommendations, we are going to fall very far behind in developing and implementing our own cutting-edge technologies and keeping our competitive advantage, scientifically and economically.”

Gurney, the Northern Arizona University researcher working with the IPCC, sees the U.S. backing out of work with the IPCC as damaging to the nation’s academic reputation internationally and at home, with emerging scientists and academics. 

“I worry about what this says to young scientists who may feel like they are underappreciated, or worse, that they are almost viewed as unwanted, that science is no longer a wanted endeavor,” he said. 

Two-thirds of Global Emissions are from Cities

The value of U.S. researchers at this week’s conference in Osaka is underscored by a bevy of practical considerations. Among them: heat waves have increasingly plagued American cities, which also produce about 70 percent of the greenhouse gases warming the climate. 

Julie Arrighi, another U.S. scientist tapped to author the IPCC’s upcoming report, said this is the first time cities are featured in a separate report, and for good reason. 

“One of the reasons it’s so important is just demographics in the world,” said Arrighi, who is representing the International Red Cross Red Crescent at the IPCC. “More than half of the world lives in cities, and that will continue to grow over the coming decades. As we look to adapt to changing risks, and reduce greenhouse gas emissions, cities will play a fundamental role.”

Arrighi, who holds a joint position with the American Red Cross and the Red Cross Red Crescent Climate Centre, said cities can be particularly vulnerable to climate disasters fueled by global warming. 

From a Red Cross Red Crescent perspective, she said, disasters are becoming more frequent and more intense with complex, cascading, compounding impacts in urban areas. Some recent climate attribution studies she worked on showed the scale of adaptation needed to reduce impacts in urban areas, with millions of people facing a growing risk of heatwaves and water shortages.

“Two-thirds of greenhouse gas emissions come out of cities and that makes them places where there are opportunities to reduce emissions.”

— Kevin Gurney, Northern Arizona University atmospheric scientist

That highlighted the need for the IPCC to focus on this topic, she said

“We’re already living in a changed climate,” she said, adding that people in cities are particularly vulnerable to climate threats. “A lot of the changes that we’re seeing that we anticipated years ago are happening today. We have further to go on the adaptation side to even catch up to today’s changed risk, but then we also have to look ahead to the coming decades.”

The new IPCC report, she added, is a critical step toward trying to stay abreast of the accelerating climate crisis.

Gurney said he started creating systems to track greenhouse gas emissions at a very granular level about 20 years ago, down to “every roadway, every block of a city.”

That level of detail, combined with new incoming satellite data, is enabling scientists to “see” Earth’s surface better than ever before and make better decisions, he said.

The information systems he built motivated him to work on cities.

“When you just look at the raw numbers of emissions around the planet, there’s no way of avoiding the fact that cities are just fundamental,” he said. “Two-thirds of greenhouse gas emissions come out of cities and that makes them places where there are opportunities to reduce emissions.”

Cities are worlds filled with millions of people who drive cars and live and work in buildings that emit vast quantities of greenhouse gases. 

“That’s the scale that we function at. And mitigating emissions or reducing emissions, is also at that scale,” Gurney said. “This is where things happen.You change roadways, you redesign buildings. It’s at that scale that most of the mitigation occurs.”