Riding the Transpolar Drift

How the Polarstern icebreaker accomplished the largest polar expedition in history — and what scientists learned 

Crew exchange and supply delivery of MOSAiC Leg 4 group in Longyearbyen. (Photo: Leonard Magerl)
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I was far away from the Polarstern, out on the ice in winter. The complete darkness of the polar night was a true pitch black. I had only my flashlight to create a bubble of light around me. Outside of my bubble, the darkness extended not only to the horizon, but 1,000 kilometres beyond the horizon. There were hungry polar bears out there. At the edge of my light, I could see ice structures that looked like sculptures. It didn’t look like planet Earth. It was some strange planet drifting through our vast universe in complete, frozen darkness.” — Markus Rex, head of MOSAiC

Few humans have ventured so deep into the vast isolation of the central Arctic during winter. Millions of square kilometres of thick ice, a whirling polar vortex and unceasing darkness usually locks humankind out of the North Pole during its coldest months. There is, however, a unique way to get there: hitching a ride on an ice floe.

Following the path of Fridtjof Nansen’s legendary Fram expedition in 1893-1896, German research icebreaker Polarstern set sail from Tromsø, Norway, on September 20, 2019, on the MOSAiC (multidisciplinary drifting observatory for the study of Arctic climate) expedition. Aboard were hundreds of researchers from 20 nations, including Canada, split into teams based on scientific discipline. After travelling a couple of thousand kilometres into the Arctic Ocean, the crew found a suitable ice floe — one thick enough to carry the Polarstern along as it was dragged across the Arctic via the major current known as the Transpolar Drift Stream.

The method for plugging a ship into an ice floe hasn’t changed much since 1893. “We took the ship and plowed it right into that thing,” says Matthew Shupe, expedition co-lead. From there, the largest polar expedition in history truly began. Divided into five legs with teams swapped out regularly by support vessels, the voyage allowed researchers to observe the Arctic environment over an entire annual cycle. The results of the numerous experiments are wide-ranging. Vitally, they give deep insight into the Arctic of today — and tomorrow. The rate of change is alarming: atmospheric scientist Markus Rex, who has visited the Arctic since the early ’90s, says there are areas his younger self would no longer recognize.

In February, expedition scientists began releasing articles on atmosphere, sea ice and ocean findings. Of note, the ice pack was more dynamic and faster drifting than expected, the result of large-scale atmospheric pressure in the winter creating a huge polar vortex around the Arctic.

The results of the MOSAiC expedition will inform the next generation of Arctic and climate science. For now, the winter ice is still considerable enough to keep us locked out of the North Pole until scientists next brave the Transpolar Drift. When the time comes, what strange planet will emerge from beyond the glow of their flashlights?


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This story is from the July/August 2022 Issue

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