About 60 years ago, at the height of the Cold War, the US designed a network of top-secret mobile nuclear launch sites buried in the Greenland ice sheet to prepare for possible war with the Soviet Union. At Camp Century, which was part of Project Iceworm, soldiers lived in the ice, which enclosed the base so it wouldn’t be completely buried in snow.

Camp Century was shut down in 1967, and the site was abandoned as Project Iceworm wound down. Back then, military planners assumed the hazardous stuff buried at Camp Century—including diesel fuel, PCBs, and some radioactive coolant—would stay locked up in the Greenland ice sheet, essentially forever. But now Greenland is warming because of climate change. Dangerous contaminants threaten to re-emerge from the ice, potentially putting people in Greenland and maybe as far away as Arctic Canada (400 km offshore) at risk.

Nuclear reactors at Camp Century in Greenland. Image: US Army/Wikimedia Commons

Camp Century isn’t the only US military installation abroad that’s increasingly threatened by climate change. A Pentagon report from earlier this year, for example, noted that half of all US bases worldwide could be at risk. But Project Iceworm is a useful case study, argues Jeff Colgan, associate professor of political science and international studies at Brown University, who’s studied this in detail. That’s partly because the question of who should take responsibility for Camp Century has become such a political hot potato. According to him, at this point it isn’t clear exactly who is responsible for cleaning it up.

Over the phone, Colgan described the secondary effects of climate change—like the release of dangerous substances, or infrastructure damage—as its “knock-on effects.” (He pointed to the release of hazardous materials in Texas after Hurricane Harvey as another example.) “It creates a whole new type of politics, and it’s becoming more important in a variety of ways.”

Colgan is author of a new paper in Global Environmental Politics that views the impact of climate change on military bases as not just an environmental problem, but as a political and diplomatic one.

Project Iceworm goes to show just how politically complicated these situations can be. Camp Century was the result of a legal treaty between Denmark and the US, since Greenland was a Danish colony at that time.

Motherboard contacted the US State Department to inquire about Camp Century, and was referred to the US Department of Defense. A Defense Department spokesperson then referred our query to the government of Denmark.

The Danish foreign ministry, which handles relations with the US and Greenland, referred Motherboard to the Geological Survey of Denmark and Greenland (GEUS), an independent research institution under the Danish Ministry of Energy, Utilities and Climate. In a follow-up phone call, a ministry spokesperson said decisions around the cleanup would be made once the science is settled.

“It’s not a high priority. In fact it’s a barely known [issue] in Washington,” Colgan told me. “The only people who are really agitated [are in] Greenland, and they don’t have a lot of leverage.”

Scientists aren’t ignoring the problem. In 2016, a high-profile paper in Geophysical Research Letters predicted that Camp Century’s site could see primarily melting conditions by the year 2090, and described in detail all the hazardous stuff buried there. “It caused quite a reaction from scientists and the political system,” Flemming Christiansen, deputy director general of GEUS, told Motherboard in a phone interview, and it spurred them to study the site further.

GEUS has been monitoring the Greenland ice sheet for years, and is now tracking the Camp Century site specifically. In the summer of 2017, Christiansen said, a weather station was installed there, and scientists used radar last year to map what is locked up under the ice. (The map should be available later this year.) Climate data from Camp Century is publicly available online, although it will take some time to begin to notice longer-term trends.

Politicians, meanwhile, have yet to sort out exactly what to do about the threat posed by climate change to military installations abroad, each one governed by what Colgan calls “ad hoc” arrangements. Colgan noted that the US Pentagon, at least, does seem to appreciate the dangers of climate change. Of the hundreds of US bases overseas, “it’s unclear how many of them are at the frontlines of climate change, like Greenland,” he said, adding that other sites, like low-lying Pacific islands, are also certain to be impacted.

Meanwhile, Camp Century is melting out. “If there is something coming to the surface, you would like to know when this will happen,” Christiansen told me. Scientists are working on that part. Now it’s up to governments to come up with a plan.