Sixty-seven scientists urged the end of “coal leasing, extraction and burning” on public land in a letter to the U.S. Department of the Interior on Wednesday, calling it essential to averting the most catastrophic impacts of climate change.

The scientists argued that the United States cannot meet its pledge to help reduce worldwide emissions enough to keep global warming below 2 degrees Celsius if it continues to produce coal on federally owned land.

“The vast majority of known coal in the United States must stay in the ground if the federal coal program is to be consistent with national climate objectives and be protective of public health, welfare, and biodiversity,” the scientists wrote.

The letter’s authors work at academic and independent research institutions nationwide—from Stanford University in California to Woods Hole Research Center and MIT in Massachusetts—and include some scientists from around the world and members of nonprofit environmental science and advocacy organizations.

The federal coal program accounts for about 41 percent of U.S. coal production. Coal extraction and production on public land generates as much greenhouse gas emissions annually as 161 million cars, according to an analysis by The Wilderness Society and Center for American Progress.

The Interior Department earlier this year launched a multi-year review of the federal coal leasing program, the first review in about 30 years. In the meantime, the Obama administration placed a moratorium on new federal coal leases. The scientists submitted this letter as part of the public comment period.

The coal industry has decried these moves, but its struggles began long before the campaign to curtail its public lands leases. Increased competition from natural gas and other energy sources, coupled with coal-specific pollution regulations has sent coal prices plummeting. Earlier this year, Peabody Energy and Arch Coal, Inc., the nation’s two largest coal companies, declared bankruptcy.

“Top climate scientists are speaking out about the need to end public coal leasing once and for all, and President Obama would be wise to heed their warning,” Shaye Wolf, climate science director at the environmental nonprofit Center for Biological Diversity, said in a statement. “It makes no sense for the federal government to undermine the climate fight by letting companies dig up more of this incredibly polluting fossil fuel from our public lands.” Wolf is among the scientists who signed the letter.

Ending the federal coal program is not only critical to meeting the nation’s climate goals, the letter argues, but also global climate targets outlined in the Paris agreement last December. The scientists cited those goals, as well as climate studies from the Intergovernmental Panel on Climate Change and prominent journals such as Nature Climate Change.

“A rapid end to federal coal extraction would send an important signal internationally and domestically to markets, utilities, investors and other nations that the United States is committed to upholding its climate obligation to limit temperature rise to well below 2°C,” the scientists wrote.

“The science is clear: to satisfy our commitment under the Paris Agreement to hold global temperature increase well below 2°C, the United States must keep the vast majority of its coal in the ground.”

Correction: A previous version of this story misidentified the one of the research organiztations as the Woods Hole Oceanographic Institution. It is the Woods Hole Research Center.