Two sources familiar with the matter said that the Trump administration had halted participation by U.S. researchers in U.N. climate assessments. This is part of a broader withdrawal of the Trump administration from climate change mitigation and multilateral cooperation.
The order to stop work affects employees of the U.S. Global Change Research Program and National Oceanic and Atmospheric Administration are involved with a working group of the Intergovernmental Panel on Climate Change.
One of the sources said that the U.S. won’t be attending a major IPCC meeting next week in Hangzhou, China plans to attend their 7th global climate assessment.
The White House refused to comment, and the State Department didn’t respond to a comment request.
The IPCC has the power to bring governments, businesses, and global institutions together with a common set of conclusions. Delta Merner of the Union of Concerned Scientists said the U.S.’s complete removal from this process was concerning.

The absence of American scientists at the IPCC will be felt. While American scientists are in attendance, they will continue to work on the climate research used by the IPCC.
Hangzhou’s meeting, which will take place from February 24-28, is expected to make some key decisions that could influence the outcome of the next assessment of climate change. This includes the role played by carbon capture and removal technology.
China’s Foreign Ministry said it did not know about the withdrawal of U.S. participants.
The U.S. and Malaysia are co-chairs of a group that focuses on ways to reduce greenhouse gases or climate mitigation.

Congress has not yet appropriated the $1.5 million pledged by the U.S. to support IPCC.
Climate scientists are not surprised by the U.S. withdrawal from the IPCC, especially after President Donald Trump announced his intention to pull the U.S. out of the Paris climate accord, claw back U.S. climate finance globally, and end international climate partnerships.
Kathryn Bowen is a Melbourne University professor and lead author of the IPCC’s 6th assessment report, published last year.
She noted that federal funding has been cut for climate science around the world.
