Scientists are about to lock themselves into an Arctic ice floe for a year
In the largest Arctic expedition yet, researchers will gather as much data as they can on the fading ice—and climate change.

Polarstern in the Weddell Sea, in the Southern Ocean. Image Credit: Stefan Hendricks, Alfred Wegener Institute
On Friday, a 400-foot-long German ship will set sail from the port of Tromsø, Norway, charting a northeastern course. For about two weeks, it will churn through the Arctic Ocean, first forging a path through water, then plowing into the region’s thin autumnal ice, until it reaches a point just north of the Siberian coast. There, the crew will cut the engine and let the Arctic waters refreeze around the vessel, clenching it like an icy fist.
Then, the real work will begin.
For the next 13 months, that ship—the research icebreaker Polarstern—will drift through the central Arctic atop a sheet of floating sea ice, guided by wind and ocean currents. During that time, Polarstern will host the largest Arctic expedition ever attempted: the Multidisciplinary drifting Observatory for the Study of Arctic Climate (MOSAiC), a $134 million endeavor to monitor climate change at the fastest-warming part of our planet.
Under the influence of rising temperatures, the summertime ice that shrouds Arctic seas has rapidly thinned and receded, now covering just 60 percent of the area it did in 1980. It’s also become shorter lived, forming and dissipating over spans of single years instead of four or more at a time. Rising air and ocean temperatures have triggered the collapse of glaciers, and expunged life from habitats both marine and terrestrial. At this rate, researchers project, there may soon be summers during which the Arctic Ocean is nearly ice-free—a reality that would warp its delicate landscape past the point of recognition.
And such transformations in the Arctic will reverberate throughout the rest of the world. Without ice to reflect sunlight back into space, the darker-hued ocean and land will absorb extra heat, nudging global temperatures higher. Rising sea levels, fed by melting land ice, could swallow coasts further south. And without the coolness of Arctic ice to stabilize the jet stream that hovers over the Northern Hemisphere, extreme weather events may become more common.

Melt ponds in the Arctic, formed by the liquid water collecting from melting ice. The evolution of these ponds will be one of the things studied by MOSAiC. Image Credit: NASA Goddard Space Flight Center, Wikimedia Commons
In the face of all this change, the Arctic remains one of the least understood habitats on Earth. No research bases can be built on its fluctuating ice, and much of the data on the region is collected via satellite.
Until now, researchers haven’t had many chances to get a close look at the fast-fading ice. But if all goes according to plan, the MOSAiC team will glimpse the heart of the Arctic—and collect intel that might help it make a comeback, while it’s still possible.
“The Arctic is changing so fast,” says atmospheric scientist Matthew Shupe, MOSAiC’s scientific co-coordinator. “The questions we’re asking are really urgent.”
By mid-October, Polarstern and its scientists will be moored into a slab of ice, where they’ll study nearly every aspect of the surrounding ecosystem and the physical, geochemical, and biological processes that sustain it through all four seasons. The data they collect will clarify our portrait of the Arctic, thereby improving climate models, informing economic policies, and more.
At any given time, the ship will house about 100 people, working in two-month stints that begin and end with the arrival of aircraft and additional icebreakers that will resupply Polarstern with fuel, provisions, and personnel. By the fall of 2020, when the ship docks in Germany, it will have supported some 300 researchers from 19 countries around the world. (Many of them will have returned to the vessel for multiple shifts.)
All that hinges on picking the right ice floe—one that’s thick and sturdy enough to support the ship, its inhabitants, and their scientific instruments without sending the whole operation bobbing back into open waters, or careening too far off course, before it spits the ship back out east of Greenland next year. Years of modeling and calculations have narrowed Polarstern’s target region, but the final decision will have to be made in real time, as the ship crunches through the frozen sea, Shupe says. That makes the first two-month leg of this trip, which will literally set the trajectory of the remainder of the expedition, “extraordinarily important,” he says. “We really are subject to the whims of the sea ice.”

A potential drift trajectory for Polarstern, which will tentatively start near 120 degrees East and 84 degrees North. Image Credit: Alfred Wegener Institute
Icebreaking ships are designed to, well, break ice, making Polarstern’s mission a bit unconventional. But it won’t be the first ship intentionally locked into Arctic ice. That honor belongs to Fram—the vessel of a Norwegian explorer named Fridtjof Nansen, who, in 1893, hitched his ship to ice in the hopes of catching a quick lift to the North Pole. Rather than fighting the ice, Nansen reasoned, he could take advantage of its natural mobility.
Nansen and Fram ended up missing the pole. Still, their three-year sojourn, which spanned more than 1,000 miles of Arctic sea, proved that this strategy was viable.
Once Polarstern has settled into the ice, its residents will set up their scientific base, which, for a year, will be the northernmost settlement on Earth. Dozens of instruments will be installed in its vicinity. Some will take measurements of the sea ice itself—its varying thickness, the chemistry that dictates its ebb and flow. Others plunge through it to peer at life lurking in the sea below, or rise to sample the atmosphere above.

A helium-filled tethered balloon being deployed for atmospheric research at Flyger’s Hut, about 2 km south of Station Nord, Greenland. Image Credit: Esther Horvath, Alfred Wegener Institute
Meanwhile, an accompanying Russian icebreaker, Akademik Fedorov, will arc around its sister ship, wreathing it in a network of autonomous monitoring stations that will take their own measurements, some up to 30 miles from base camp. After delivering the equipment, Akademik Federov will return to Tromsø alone.
“All of this information is going to [come together] to give us a cohesive picture of the interactions between water, sea ice, and atmosphere,” says Carolynn Harris, a polar ecosystem scientist at Montana State University, and one of 20 students in the MOSAiC School, a six-week training program for early career scientists aboard Akademik Fedorov. “This will tell us about the future of climate change.”
Even after the crucial first leg draws to a close, plenty of obstacles will remain. By then, Polarstern will be catching the last rays of light before polar night sets in, blanketing the region in nearly six months of darkness. With the ship rooted in place, instruments will need to remain operational—and morale high—through extreme wind and snow, Shupe says.

Scientists trudging through the ice in the Weddell Sea in the Southern Ocean. Image Credit: Mario Hoppmann, Alfred Wegener Institute
There are living dangers, too: the Arctic’s polar bears, which weigh up to 1,500 pounds and can handily disembowel similarly-sized seals. To protect the team, a 2,000-foot perimeter will be established around the ship, ringed with tripwires and a daily patrol squad armed with rifles.
Researchers who need to take measurements outside the safe zone, or during off-hours, will need to be accompanied by a teammate who’s been trained as a part-time guard—an opportunity that appealed to United States Coast Guard veteran Brandi Downs, now an electrical engineer at Ohio State University. Most polar bears are just curious, she says, and might be scared away with as little as a flare. Only in the direst of situations would a shot be fired.

Two polar bears on Arctic sea ice. Image Credit: Mario Hoppmann, Alfred Wegener Institute
But Downs’ biggest worry is a bite from something far more insidious: frost. In the dead of winter, temperatures are expected to plunge down to about minus 50 degrees Fahrenheit—well below the point at which digits or entire limbs can freeze off unprotected bodies. “The ice really draws the heat from your feet, through your boots,” says Downs, who will be operating instruments that measure the thickness and salinity of sea ice. “When you’re working, you need to have gloves with dexterity, or have the ability to take your gloves off and still work with a metal instrument.”
Still, the trip, which will take Downs away from her husband and five-year-old son for two months, is worth the hardship. “It’s kind of a lifelong dream to be able to do this,” she says.
For Shupe, who’s been involved in MOSAiC’s planning for more than a decade, Friday can’t come fast enough. “I’m just excited to get underway,” he says. “I’ve been thinking about this for 11 years...and wow. It’s finally here. Once we set sail, that will be exceedingly elating for me.”