Stopped by global warming

Statsraad Lehmkuhl had to turn back just days before reaching Port Inlet, the eastern entrance to the Northwest Passage. The ship is polar-certified to sail in Open Waters, meaning less than ten percent of the sea covered by ice. Forecasts indicated more ice than that in the western part of the passage, and Transport Canada withdrew the sailing permit.

Many who commented on this on social media take it as a sign that the ice in the Arctic Ocean is not disappearing as climate scientists warn. But they are wrong - sea ice extent is at a record low this year, and it is in fact the warming of the north that halted Statsraad Lehmkuhl's voyage.

There are two types of ice in the Arctic Ocean.

There is sea ice, formed when seawater freezes. And there are icebergs, from massive cliffs of ice to small chunks, formed where the glaciers in Greenland meet the sea and breaks apart. Sea ice forms on the ocean - glacier ice forms on land.

Bergy waters

It was glacier ice that stopped Statsraad Lehmkuhl, the kind of conditions ice pilot Stèphan Guy calls “bergy waters.”

– The ship could not continue because there were too much bergy waters. What happens with global warming is that glaciers get weaker and weaker, and pieces of ice are falling into the water. And then these pieces of ice we call icebergs, or bergy bits, are drifting within the ocean. So it's not related to the cold climate, that we have more bergy waters, but it is related to global warming, Guy explains.

Researcher in climate dynamics, Rebekka Jastamin Steene at the Arctic University of Norway, agrees.

– The sea ice is melting because of climate change. There is less of it. But at the same time, the warming causes the glaciers to calve more, resulting in more icebergs floating around in the ocean.

Stèphan Guy began his career as a captain in the Canadian Coast Guard and has over 40 years of experience aboard icebreakers and other vessels in Arctic waters. He was involved in planning Statsraad Lehmkuhl’s voyage and was on board en route to the Northwest Passage. That the ice should stop the ship from sailing came as a surprise.

– A voyage through the passage seemed realistic based on the amount of ice we’ve seen over the last ten years. We were unfortunate, but in the end, nature decides here, not us.

Sharp decline

The extent of sea ice in the Arctic varies with the season, largest in mid-March, smallest in mid-September.

Both winter and summer extents are declining dramatically. Since satellites began monitoring the ice in 1979, the extent has decreased by 13 percent per decade, according to the U.S. National Snow and Ice Data Center.

The winter of 2025 saw the lowest extent in the last 35 years, and this summer’s extent so far matches the record low of 2012.

At the same time, the ice is getting thinner. From being two to three meters thick - and up to five meters at its thickest, more and more of it is now only one to two meters thick.

The “blanket” is gone

Warmer air and warmer ocean water are the main reasons for melting Arctic ice, but the loss of ice at sea further accelerates warming.

Less white ice means less sunlight is reflected in summer. More heat is absorbed by the dark ocean, causing even more melting. In winter, the effect is reversed - the ice acts like a blanket, preventing heat from the ocean from warming the cold air above.

Steene calls this mechanism “Arctic amplification.”

– It is the reason the Arctic warms even more than the rest of the planet. In fact, it is warming between two and five times faster than the global average.

One swimming pool per second

The thickness of the inland ice covering most of Greenland also varies throughout the year. Glaciers gain mass from November through March and shrink in the summer months.

Ice on land is also disappearing at a rapid pace.

For 28 consecutive years, more ice has melted in summer than has been added in winter, according to the Geological Survey of Denmark and Greenland.

The losses are not small - an average of 150 million liters of water per minute, day and night, all year round. That equals the volume of an Olympic-sized swimming pool every single second.

The meltwater ends up in the ocean, and in 2024 it contributed to a sea level rise of 0.2 mm.

– Worries me greatly

Stèphan Guy was young when he fell in love with the Arctic.

– Sailing here at the age of 19, discovering these very isolated areas, the Inuit community, the landscape, the remoteness, and the history - was an eye-opener. I was fascinated by the stories of the early sailors who came to these waters. I thought they were men of steel, and I liked the idea of following in their footsteps, he says.

– It made me feel good about being here. To this day, I’ve never lost the pleasure of coming back, feeling like a discoverer. I know I’m not, but I pretend I am, and I still enjoy sailing these waters and having that sense of being an explorer.

More than 40 years at sea in the Arctic means that Guy has seen the climate changes first-hand, and he is clear:

– What is happening is dramatic. We see a lot of change in the overall Arctic temperatures.

More open water in the Arctic leads to more ships sailing through the Northwest Passage, and that worries Guy.

– I’m a guy who’s been in the marine business all my life. I’m not against marine traffic, but the number of ships sailing these waters is increasing year after year. I believe there’s still a lot of work to be done to make these waters safer and to build better infrastructure to support the traffic - not only for search and rescue, but also to provide proper logistics for any ship. There are almost no docking facilities in the Arctic, no refueling stations, and no towns prepared to receive large numbers of tourists like we see with cruise ships, he says.

– Nature also suffers the burden of such traffic, look at the history of all major waterways around the world. The pressure we put on the marine environment speaks for itself, and we are about to repeat the same mistakes in the Arctic. That worries me greatly, and I hope our leaders will find a solution to prevent too much stress on this very special environment.