THULE AIR BASE, Greenland—On the last Saturday in September, ice had already begun to spread across the Arctic waters at the dock, closing the port for months to come. The temperature was 24 degrees Fahrenheit. Snow swept across the airport runway, with 15-mph winds cloaking the base in a heavy layer of white. 

A snowplow rumbled back and forth, temporarily clearing the runway before a fresh wave descended. Officials had released a warning in the morning categorizing the storm as an Alpha-level threat and cautioning that it would escalate to Charlie level the next day.

Located just 900 miles south of the North Pole, Thule Air Base is so remote it can only be accessed by chartered flights. If the weekly rotator flight out of Baltimore could not take off—it was already a day late because of technical issues in New Jersey—the departing passengers would probably be stuck in Greenland until Tuesday.

In the waiting room, tension hovered heavily in the air. One man, his fidgeting hands tucked under his legs, had yet to meet his grandson. “My wife will kill me if I don’t make it back,” he said. 

Also fretting was the only barber on the base, Shaina Simpkins, who had been at Thule for seven months. “I just want to go home,” she said. “And at this point I don’t even know when I’ll be going home—I hate it.” 

As for those due to leave on the rotator flight, this would likely have been their last trip home before darkness descended on Thule for the next six months. From November to February, the sun would not rise at all. 

In just the way summer brings the midnight sun, winter would coat the base in an endless black. Every room is therefore equipped with a sun lamp, and all personnel are supplied with Army-issued vitamin D pills. 

Thule’s chief master sergeant, Christopher Clark, takes an optimistic view of life on the isolated base. “Where you find the worst conditions, you find the best morale,” he said of its tight-knit community of military personnel, contractors and scientists. “We have a common enemy of the snow, the cold, the elements.” 

But a more menacing enemy than the historically bitter cold is imperiling the base’s mission and its very survival: climate change. 

Thule is now facing its most critical military role since the end of the Cold War, but global warming is hindering its mission: Rising Arctic temperatures are thawing the permafrost on which it was built seven decades ago. From cracks in the 10,000-foot runway to the slanting of the floor in its banquet hall, the air base is crumbling.

Thule is the northernmost U.S. military base in the world and the first outpost that would detect an imminent attack by Russia on the United States. It is the only U.S. operation that can monitor all of Russia’s missile activity, sending a warning within 60 seconds to decision-makers at the Pentagon in Washington and bases in California and Colorado.  

Then there is a growing regional challenge. The melting of Greenland’s ice sheet has opened the way for icebreakers to sail from Russia, allowing the country to establish trade routes and military infrastructure in the Arctic. For China, these new routes present similar possibilities.

The American military is belatedly scrambling to address the base’s deterioration, particularly the possibility that an infrastructure failure could disable Thule’s radar tracking. The Americans can’t risk that, even for a second. 

“We cover the entirety of Russia,” said Lt. Col. April Foley, who oversees the radar at Thule. “We need defenders at all times.” 

“Defenders,’’ a popular Air Force moniker invoking that branch’s mission readiness, resonates deeply at the base these days because of Russia’s war of aggression in Ukraine. With the fighting continuing and Russian missiles raining down on its harried population, Western governments are bracing for the possibility of direct conflict between Russia and NATO.   

A Onetime Marvel of Engineering

Thule has been critical to American security since 1953.  Constructed in just 60 days, it was touted as an engineering masterpiece: Buildings were drilled into the ice, with the permafrost serving as a substitute for cement.

Over time, problems began to emerge. The base’s buildings had been designed to minimize any thawing effect from the heat within them: Structures that had to be at ground level, like aircraft hangars, had two stories with cold air circulating between them, and the others were well above ground. As long as the 1,600-foot-thick permafrost stayed frozen, the buildings were safe.

But the engineers could not anticipate how dramatically climate change would affect the permafrost. In 2009, the summer’s unprecedented heat caused some buildings to sink into a slushy mix of water and gravel, and vehicles became trapped on the base’s soggy unpaved roads. Last month, new research showed that the first decade of the 2000s was the warmest 10 years on record in Greenland in at least 1,000 years.

Today, the original flat-topped buildings show their age, with paint peeling from the walls and rusting pipes running along their edges. Structural cracks resulting from the melting foundation are in evidence everywhere.

Building on permafrost involved “a lot of experimentation,” said Col. Brian Capps, the base’s commander. “The facilities we’re seeing with sinking foundations and things like that is because we were experimenting.” 

Stuart Pettis, an Air Force colonel who served as Thule’s commander in 2015-16, noted that any sort of construction in Thule’s environment would be exceptionally challenging. “Everything depends on a lasting permafrost,” he adds. “If you melt the permafrost, it never comes back. You have to keep that cold.” 

An Evolving Mission 

Constructed as a follow-up to a secret American mission in the region during World War II, Thule Air Base housed 10,000 personnel at its peak in the early 1960s. Today the total is at 650, a small number of dedicated Air Force and Space Force personnel who run the base’s radar and satellites. Scientists dip in for months at a time to conduct research. Visitors are rare, if not almost impossible. It’s a nonfamily duty station, the occasional pierce of a child’s laughter heard only when Greenlandic locals stop in or pass through or when a base family member makes a short visit. 

Over the last seven decades, Thule has been through countless iterations. In the beginning, it was a Strategic Air Command Installation, designated as a testing site to observe how weapons responded in extreme weather. Later it became the stage for radio communications, and in 1959, the host for materials for a nearby top secret nuclear project called Camp Century. The Ballistic Missile Early Warning System was added in 1961, and Thule became an Air Force Space Command base overseeing an array of U.S. satellites, launchings and cyberactivity in 1982.

Spanning 264 square miles, the base consists today of several dozen buildings, 65 miles of unpaved roads and the 10,000-foot year-round runway. Thule operates on generators powered by imported jet fuel, and there are electric outlets everywhere to ensure that every car is plugged in and warm. Free massage chairs are peppered across the base for comfort, and almost every building has arcade rooms and large television screens to relieve the tedium.

Problems can take months to fix.  Over 60 miles from the nearest town, the base is so remote that all of its supplies must come in by aircraft or through the port, open from just July to August every year. By that September Saturday, the base’s single tugboat had already been retired for the season, towed to shore as dusts of snow accumulated across its exposed ridges. 

Still, “there’s an investment going in to right some of those wrongs,” Capps said of the structural problems.  

In December, the U.S. Department of Defense announced that a new maintenance contract worth $3.95 billion had been awarded to the newly formed company Inuksuk A/S, owned by enterprises in Greenland, Denmark and the United States. The money will be devoted to critical improvements like upgrading the base’s energy and communications infrastructure, addressing climate risks and renovating dormitories. 

Sgt. Christopher Clark, the base’s senior enlisted leader, said he was particularly worried about Thule’s community center, a morale-building lifeline where many gather in the winter months at large round tables surrounded by soft red armchairs. The walls are lined with old wooden armoires brimming with bottles of wine and antique wine glasses. This is where weekly bingo is hosted as well as events like the base’s annual ball, which generates days if not weeks of eager anticipation. 

But the crack lines running up the walls and across the ceiling and the slanted floor threaten the prospect that socializing can continue. 

Structural engineers were on site last fall to assess the structural damage. There’s a risk that the building will need to be permanently closed because of the possibility of collapse. 

“Hopefully we can put in enough safety mitigations to make sure we can get through the winter and we don’t have to find an alternate location,” Clark said. “Because as you can imagine, when it’s dark out, you don’t really have a lot of other places for folks to go to get together.”

But because of Russia’s war with Ukraine and the support missions the United States is running out of the base, such as its key Ballistic Missile Early Warning System, some renovations have been placed on the back burner. 

A major renovation to Thule’s radar had been scheduled but has been indefinitely postponed because of the Russian invasion. “The radar couldn’t be down during the heightened state,” Foley said. 

A Scolding From the Pentagon

Such delays may be typical in any case. Last April, the U.S. Department of Defense issued a report lambasting leaders at its six Arctic and sub-Arctic military bases for failing to carry out climate contingency planning as required by U.S. law. Those leaders, investigators found, “did not comply with requirements to identify current and projected environmental risks, vulnerabilities and mitigation measures.” 

Base leaders were too focused on current conditions, it continued, and failed to analyze long-term climate threats. The report also faulted the Pentagon itself for providing inadequate guidance and resources for assessing the implications of climate change.

The Department of Defense manages over 1,700 global military installations along coastlines, areas that have already suffered the effects of climate change. In 2019, the Pentagon found that at least two-thirds of the 79 installations investigated were suffering from damage inflicted by recurring floods, with another half subject to extreme weather like droughts or wildfires. 

Most of the information about Thule Air Base is blacked out, but the report states that major renovations are planned at the base through 2025. 

A separate 2021 Climate Risk Analysis defined climate change as a serious threat undermining the armed forces’ ability to secure and defend the United States. That year, President Biden ordered defense officials to integrate climate impact and risk management into their plans for all military installations. 

The document includes photographs of cracks and depressions on the runway and in aircraft hangars caused by water freezing and melting as the permafrost thaws. There are also pictures of damage in the armoring used to prevent flooding along embankments.

The Dire Threat of a Melting Ice Sheet 

Second only to Antarctica in scale, Greenland’s ice sheet covers 80 percent of the country and is up to two miles thick. Scientists believe the ice may be 18 million years old. Antarctica excluded, the ice sheet is four times the size of all of Earth’s other ice and glaciers combined. 

According to the World Meteorological Organization, however, Greenland lost enough ice on one day alone last summer to submerge the entire state of Florida in two inches of water. Already the largest single contributor to rising sea levels, with a millimeter added every year, the island’s melting ice is expected to increase the global sea level by at least 11 inches by the end of the century. If the entire ice sheet melts, it would add 24 feet of water to the sea level, flooding every major coastal city in the United States, from Miami to San Francisco. 

These glaciers are libraries of history, fossilized stories that researchers travel from around the world to unearth: Greenland may be the most studied ecosystem on the globe. And underneath are years of buried American history, hazardous remnants of the Cold War that could be uncovered as the ice melts.

There was the surreal Project Iceworm, for example, which involved a series of subterranean tunnels, a mobile reactor and a military base, Camp Century, intended to host up to 600 nuclear missiles that could be launched in the event of a war with the Soviet Union. Opened in 1959, it was dismantled and abandoned in 1967 when the shifting ice caps made the base uninhabitable.

Fears about contamination arose recently when climate change threatened to expose the nuclear remnants, and scientists from the Geological Survey of Denmark and Greenland, or GEUS, have been tasked with monitoring the problem. The melting also exposes ancient bacteria and viruses, which scientists warn could one day unleash a pandemic.

Nigel Baker, a geologist at GEUS who has devoted his career to exploring minerals across the world, has spent the last three summers in Greenland. He documents the melt from the ice sheet and worries about the impact: His office in Copenhagen is decorated with maps that frame  Greenland’s silhouette with thermal colors to highlight the threat of rising temperatures.

“Last summer, it rained at that weather station,” he said, gesturing toward one location. “It’s never rained on the middle of the ice sheet. It should be impossible to form a rain cloud. And there wasn’t even a rain gauge on this weather station, because why would you put one? They never arranged that. These are very real indications of how serious this problem is.” 

He points to another map he designed. Dotted lines show how much the ice has receded since 1934. Small increases are registered in some years, but the loss from 2003 to 2008 is larger than that recorded in the seven preceding decades combined. And now the ice is melting faster than ever. 

Baker points to two red triangles that line Karrat Fjord. They mark a natural disaster that left four people dead: In 2017, a landslide off of Greenland’s west coast caused a tsunami so rare and so severe that it was initially thought to have been the result of a large-scale earthquake. Beyond the death toll, 45 buildings, including people’s houses, were completely washed away. 

Online videos of the event show fishermen scurrying from the beach as the water inundated the land. In only seven minutes, waves over 300 feet tall crashed onto the shore, plunging into the town of Nuugaatsiaq 20 miles away.

Up to that point, no one had assessed the risk of a climate change-induced landslide in Greenland, Baker said. But thawing permafrost and increased rainfall can undercut cliffs, exacerbating the possibility. 

Russia and China Seize On an Opportunity 

Near Thule Air Base, over 35,000 cubic meters of ice are breaking off from the Sermeq Kujalleq Glacier each year. Eruptions reverberate across the still landscape, the boom of the ice fjords calving after millenia.

“You can drive up this road and go to a place called The Secret Place that overlooks that fjord,” Clark said. “You can sit there and you can just listen to the icebergs break off the glacier.” 

The season of ice-free travel in the Northwest Passage linking the Atlantic and Pacific now runs from July to September. Before 2007, the passage had been inaccessible, but the summer heat that year finally opened a pathway. 

Since then, Russia’s emergence as a top player in the Arctic has stirred strategic concern, especially as the Kremlin’s military decision-making came to be seen as more volatile and dangerous. In 2014, Russia began expanding the construction of airfields in the Arctic and refurbishing older sites. Satellite imagery reveals the recent deployment of cargo aircraft and interceptors at its Nagurskoye Air Base.

“There have been about 472 different infrastructure projects in the last five years, including military bases and ports for search and rescue and trade, upgraded or built around the Northern Sea Route,” said James Rogers, an Arctic security expert and associate professor of international politics at the University of Southern Denmark. The 2,500-mile route runs from the Barents Sea, near Russia’s border with Norway, to the Bering Strait between Siberia and Alaska.

In 2019, Sergei Shoigu, then the Russian defense minister, announced that the country’s Northern Fleet in the Arctic would receive 368 units of Russia’s latest weapons and military equipment. The region now hosts the bulk of the nation’s modern arsenal, and Russia only continues to expand in the Arctic as the war with Ukraine rages on. 

“If Russia has its nuclear-armed intercontinental ballistic missiles stationed in the Arctic, they’ll be launched from the Arctic,’’ Rogers said. “And they’ll be launched across the north of the world towards North America.”

“You have to have incredibly sensitive radar and data to detect if there is ever a launch,” he added. That’s where Thule’s ability to monitor from Greenland comes in. 

Greenland also sits within what is known as the Greenland-Iceland-United Kingdom Gap, a triangular strategic route that the United States has monitored by submarine, satellite and other means since the advent of the Cold War. The area comprises a 200-mile stretch of ocean between Greenland and Iceland and a 500-mile gap between Iceland and Scotland. 

The GIUK Gap is currently the main point of entry into the Atlantic Ocean for Russia and China, and the only thing standing between Russia’s powerful naval fleet and North America. Thule plays a key role in securing those approaches to North America: Any move the Russians make, the base is watching.

‘The Russians Are Attacking Us’: A Local Perspective

Last month, U.S. F-35 aircrafts were deployed for the first time to Greenland. The exercise was part of a long-planned series of drills to assess the U.S. Air Force’s readiness to defend the United States in and from the Arctic. At the same time, the Russian Aerospace Forces were conducting similar tests in the region. 

In 2021, the Danish government unveiled a 1.5 billion Danish krone ($230 million) spending package to improve its monitoring of Greenland. Rogers said the money was pledged after the U.S. pressured Denmark to invest more in security surveillance of “unwanted guests” like Russian submarines.

In northern Greenland, Russia’s invasion of Ukraine may be fostering a greater appreciation of Thule Air Base among locals. Among them is Miyuki Doarana, a university student and climate activist who grew up in the town closest to the base, Qaanaaq. Over the years, she delighted in visiting the base’s canteen, taking part in its prize competitions for children and receiving presents from Santa Claus there.

Doarana recounts how a friend recently spotted a shooting star while out for a walk and assumed for a few worried seconds that it was a missile targeting the base.

When they spoke later, “he joked, ‘Now the Russians are attacking us,’’’ she said. “I don’t know if he was scared or not, or if he was thinking a lot about it, but Thule Air Base is there and there’s the possibility of war—it’s on people’s minds.”

Another threat looms: From the joint use of ports and airfields to shared research and intelligence, China has been capitalizing on its relationship with Russia to expand its presence across the Arctic. Despite being 900 miles from the region, the nation is an accredited observer at the Arctic Council, which promotes intergovernmental cooperation. And according to NATO’s secretary general, Jens Stoltenberg, China plans to build the world’s largest icebreaker for use in far northern waters.

This news arrives, many note wryly, when Russia already has a fleet of 40 icebreakers, compared with two aging U.S. vessels.

“With climate change, everything is going to melt, so there will be a point where in the Northern Sea, you need icebreakers that can cut through,” said Rogers, the security expert. “The U.S. has two, and one of them is decrepit.” 

Biden’s latest Arctic plan includes the construction of three new polar security cutters, the first icebreakers to be manufactured in the U.S. in 45 years. The Coast Guard has been weighing the purchase of a used icebreaker from a private company to help fill the gap until those cutters are delivered.

“You shouldn’t mention icebreakers to Americans, they are so embarrassed about it,” said Rasmus Leander Nielsen, the head of Nasiffik—Center for Foreign and Security Policy, a research institute at the University of Greenland at Ilisimatusarfik. “You shouldn’t even talk to them about it. They think it’s shameful that they are so far behind.” 

In November, Russia launched its two latest icebreakers, the first in the world to be nuclear-powered, in Arctic waters. Each is 568 feet long, capable of penetrating ice that is nine feet thick, and equipped to maintain a year-round presence in the region. Attending the ceremony by video link, President Vladmir Putin said the vessels would “strengthen Russia’s status as a great Arctic power.” 

The same month, Russia used an icebreaker to send its second-ever crude oil shipment through the Arctic Circle to China. The voyage of roughly 15 days from Russia’s Baltic ports to China took half the time of the conventional route through the Suez Canal, in an apparent bellwether of significantly shortened shipping times. 

Russia’s strength in Arctic waters has also sowed fear of sabotage in the West. In April 2021, a cable used to monitor activity on the Arctic seafloor was ripped away in Norwegian waters, and in January 2022, a fiber-optic cable at the world’s largest satellite ground station, in the Svalbard archipelago off Norway, was severed. Last September, amid high tensions over the war in Ukraine, major leaks suddenly erupted in the Nord Stream 2 gas pipelines running from Russia to Europe. Most Western security experts have attributed the sabotage to the Russians.

Rare Earth Minerals Beckon 

China, meanwhile, has invested over $90 billion above the Arctic Circle in infrastructure and other projects, according to U.S. officials, with the goal of creating a “Polar Silk Road” for trade. But Beijing knows that it cannot expand in the Arctic on its own. It needs Russia, and the Arctic relationship between the two has become increasingly beneficial for both nations.

Beijing has a 30-year contract with Russia to import gas from the Yamal fields in Siberia and a 20 percent stake in Yamal LNG, a liquefied natural gas company in the Russian Arctic. Russia is relying more on Chinese technology to support its gas tankers as Western firms have backed off from the country in response to its aggression in Ukraine.

China has also redoubled its efforts to purchase property and otherwise expand its presence in Greenland, having long since overtaken the United States as the largest producer of rare earth minerals. China already accounts for 85 percent of global output and has now set its sights on Greenland’s rich ore deposits.

The mountains surrounding the bucolic town of Narsaq in southern Greenland have been estimated to contain a quarter of the world’s rare earth minerals, potentially a billion tons. Under its ice sheet, Greenland is believed to harbor minerals needed to power modern technology in addition to most of the planet’s undiscovered oil.

Greenlandic officials have “been really working on attracting Chinese investors and companies,” said Ulrik Pram Gad, a Greenland expert and senior researcher at the Danish Institute for International Studies. “And now it’s clear that the U.S. wouldn’t accept that.” 

In recent years, China has offered to buy the Kvanefjeld rare-earth mining site, underwrite the construction of three airports and buy an abandoned naval base in Greenland. All three offers were rejected by the Danish government after reported pressure from the United States.

The Kvanefjeld mining site suddenly “wasn’t for sale anymore, and it dawned that it was Americans who did that,” Pram Gad said. “Now it’s two Danish soldiers that are walking around there, keeping it open.”

A Reckoning for Thule

Thule is the largest U.S. base in the world, with its various on-site missions operating miles apart from one another. Historically, this scattering was intended to provide a safe distance for base camp from the nuclear radar, but today it means upward of a 12-mile drive along the base’s gravel roads. 

It also means that when a storm descends on Thule, the severity of the weather often renders the base impossible to navigate, with the lack of visibility so blinding that base members can barely see their fingers in front of them. They may find themselves trapped at their work sites for days at a time, sleeping in windowless rooms that fit no more than a bed. Communal spaces like movie theaters, bowling alleys and fitness centers become their second home, with aging DVDs a solace in the evening. 

Being stranded can be highly dangerous, Clark warned. He jokes that it was easier to evacuate troops from Afghanistan than it would be in Thule. 

In a vehicle accident on the base, “we had a rollover and had to medically evacuate two members for follow-up care,’’ Clark said. “It took us three days to get them out of here.” 

For the U.S. military, the inaccessibility also drives up costs. Based on a reading of publicly available base contracts, Thule is its most expensive overseas base to operate, a drain of more than $100 million a year. That is 10 times the amount needed for the average Air Force base. Much of the expense is associated with the remote location, given that all of Thule’s supplies must come in by aircraft or the port open a few months a year. 

With the United States now making up for lost time on the climate challenge, the cost is set to soar. While the Pentagon’s heavily censored climate resiliency report gave no specific figure on improvements at Thule, it notes that billions of dollars will be invested across Arctic bases through 2025. (The other five U.S. bases in the Arctic are in Alaska.) 

At an Arctic Circle forum hosted by Greenland last August in its capital, Nuuk, Doug Jones, deputy assistant secretary in the State Department’s Bureau of European and Eurasian Affairs, emphasized the need for an Arctic free of conflict. He reminded the 400 participants that NATO was an ally, and that the U.S. was seeking to embrace nontraditional forms of security in fighting regional threats in the Arctic, including climate change. 

“The need for a strong deterrence and defense is more important now as we confront and we see, as Russia has made it clear, it is willing to use force to achieve its aims,” Jones said. The United States needs to “confront the greatest threat to transatlantic security since the Cold War.”

Back at Thule, U.S. soldiers are mindful of their renewed relevance to their nation’s defense, even as climate change threatens their base’s structural integrity. 

On a wall in the 12th Space Warning Squadron building, the site of Thule’s crucial Ballistic Missile Early Warning System, are handwritten testimonials from base members who spent wearying days at their posts and, when a storm marooned them there, nights, too.

“I was out here fightin’ the war at the top of the world,” someone has written beneath a little sketch of a turtle.