Why a Warming Arctic Has the U.S. Coast Guard Worried About the Rest of the Country

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One of the perks of going out on a U.S. Coast Guard icebreaker in the Arctic is something called Ice Liberty. Ports are few and far between when you’re north of the Arctic Circle, so instead of shore leave, Coastguardsmen and women will locate a large slab of floating ice, cordon off a safe area, put up a watch for polar bears, and throw a football around. It’s cold, but worth it, says electrician master chief Mark Hulen, who, over the past two decades, has gone out for Ice Liberty on every one of his last six Arctic missions with the Coast Guard. But this year, as the Coast Guard cutter Healy —one of two ice breakers in the U.S. Fleet—traversed the Arctic from Seattle to Baltimore via the Northwest Passage, Ice Liberty wasn’t an option. “We struggled with finding a good enough piece of ice to stand on,” he says. “Nothing was thick enough.”

A small disappointment for Hulen and his crewmates is a warning sign of things to come. The Arctic is warming at roughly twice the rate as the rest of the world, and summer sea ice cover has declined to unprecedented lows. Arctic sea ice minimums are measured in September, before the winter starts a new cycle. This year’s extent was tied for seventh lowest in 43 years of recordings (2020 was the second lowest). Overall, minimum sea ice extent has decreased by more than a third since 1979. That means what would have been work for an icebreaker 40 years ago was largely smooth sailing this time around. But that doesn’t mean things will get any easier for the Coast Guard. In fact, it’s likely to get a lot harder. “A warming Arctic means more work for the Coast Guard,” says Admiral Karl L. Schultz, commandant of the U.S. Coast Guard. And not just in the Arctic, but across the United States. “There is that old saying that what happens in Vegas stays in Vegas,” he says. “Well, what happens in the Arctic doesn’t stay in the Arctic.”

That sea ice decline has critical effects on climate and weather, says oceanographer Larry Mayer, director of the Center for Coastal and Ocean Mapping at the University of New Hampshire, and the lead scientist on the Healy expedition. “The greater extent of the open water in the Arctic is having a severe impact on storminess in North America. A lot of the anomalous weather patterns we’ve seen over the past few months are really a direct result of that.”

By some estimates, we could start seeing consistently ice-free Arctic summers as early as 2035 and certainly by 2050 if fossil fuel emissions are not radically reduced, according to a study published last year in Nature Climate Change. For centuries explorers had sought a sea route through the Arctic Archipelago north of mainland Canada. Such a route, dubbed the Northwest Passage, would dramatically shorten shipping times between the Pacific and Atlantic oceans. In 1906, Norwegian explorer Roald Amundsen was the first man to successfully navigate the passage by boat. But the perennially ice-bound route was never easy. By the 100th anniversary of Amundsen’s successful transit, only 103 other transits had been completed. But as summer sea ice declines, the passage becomes increasingly viable. Since 2006, cruise liners, pleasure yachts, ice breakers and other vessels have transited the Northwest Passage more than 200 times. Easy access to the top of the planet opens up immense opportunities for resource extraction, tourism and shipping traffic. It also opens up the region to conflict, ecological disaster, and, for both the Canadian and U.S. Coast Guards, the potential for increased search-and-rescue operations as explorers and tourists venture further north in search of adventure.

On Sept. 6 Admiral Schultz joined his Canadian counterpart on the Healy to observe a joint search-and-rescue exercise in the Northwest Passage. TIME was invited along. As crewmembers raced to rescue a boat full of stranded and drowning mannequins in the vast, frigid expanse of Resolute Bay, Schultz spoke to TIME about what a warming Arctic means for U.S. foreign policy, maritime security and Arctic governance. And while he covered the expected geostrategic implications of trans-Arctic shipping routes and newly accessible mining resources, he returned repeatedly to the issue of climate change. It’s a subject impossible to ignore up in the Arctic. “Over the course of my 40-year Coast Guard career we’ve seen a 31 to 32% reduction in the amount of ice in the Arctic. That’s palpable,” says Schultz.

Sea ice reflects 80% of sunlight back into space. When there is no ice, the darker waters absorb up to 90% of that solar energy, according to the National Snow and Ice Data Center. “It’s like parking a black car and a white car next to each other on a sunny day,” says Schultz. “Take the thermometer inside, and you will see the black car is going to be a whole lot hotter.” The more the ocean absorbs the sun’s rays, the warmer it gets, which in turn melts even more ice in a continuous feedback loop. The effect stays through the winter, resulting in a decline of multi-year ice—the thick layers packed together over the course of years that make for good Ice Liberty sessions—which means at the beginning of the following summer, there is even less of an ice base to start from.

The Arctic, says Schultz, acts as the planet’s refrigerator. When it stops functioning the effects are felt globally, and not always predictably. A study published in Science last week drew strong links between a warming arctic and the deep freeze that devastated Texas in early 2021. “What we are seeing here is a harbinger for weather across the globe,” says Schultz. When the Arctic warms, there is less of a temperature difference between the northern and southern latitudes. That in turn weakens the jet stream, the band of wind that circulates the globe in the upper atmosphere, driving weather patterns. “When the jet stream is in a weaker state it tends to take these bigger north–south swings,” says climatologist Jennifer Francis, acting deputy director for the Massachusetts-based Woodwell Climate Research Center. It also moves more slowly, which means that the weather patterns stay in place longer. Both the heat wave in the Pacific Northwest earlier this summer as well as the droughts and subsequent wildfires that have plagued the Southwest and California can be attributed to this effect. So too can the rapid intensification of Hurricane Ida and unusually wet summers on the east coast. So even though those extremes seem like polar opposites, they are, in fact, two manifestations of the same phenomenon. “Those are all tied to the fact that the globe is warming so fast, and that what is happening in the Arctic is accelerating that warming,” says Francis.

A third of Americans were impacted by extreme weather events over the past three months, according to a recent assessment by The Washington Post. The Atlantic hurricane season of 2021 is shaping up to be just as bad, if not worse, than 2020’s record-breaking season. As someone who has served in the Coast Guard since 1983, and as its commander for the past three years, Schultz has had a front row seat to some of the worst weather-related disasters the U.S. has ever seen. More are bound to follow.

Just because Hulen and his fellow crewmates couldn’t find a good enough slab for ice liberty doesn’t mean the Healy saw nothing but open waters. Earlier in the transit, the icebreaker encountered a passage clogged with towering, jagged fragments of broken ice that had been compacted together by severe winds. Ridged ice, as the phenomenon is called, is much more dangerous to traverse than what is known as fast ice—flat slabs attached to land that make for easier ice-breaking. As multi-year ice declines, ridged ice will be more common. A warming Arctic means the Coast Guard will be navigating a more challenging route, both north of the Arctic Circle as well as further afield.