On an icebreaker, scientists study the ‘Last Ice Area’ before it disappears

Crews aboard the Canadian Coast Guard research ship Amundsen recently made it to the edge of the Last Ice Area, a region north of Ellesmere Island and Greenland in the Arctic Ocean that harbours the oldest, thickest sea ice.

There, researchers conducted an in-depth exploration of environmental conditions, examining water, sediments and organisms among other features. The first-of-its-kind expedition aims to document the area’s ecosystem before it undergoes massive change.

Researchers predict the Arctic could largely be ice-free in summer as early as the 2030s. As the planet warms, summer sea ice is projected to persist the longest in the Last Ice Area, making it a refuge for ice-dependent species.

But there are signs that the region is already on the brink of transformation. Earlier this year, researchers studying sediment cores concluded that summer sea ice may vanish from the Last Ice Area within a few decades – if not much sooner.

“It is a unique and very important region that has ecological and climate significance,” said Audrey Limoges, a paleoceanographer and associate professor at the University of New Brunswick.

The loss of summer sea ice would drastically alter the local environment and ecosystems it supports. On a global scale, melting sea ice could also disrupt ocean circulation patterns and cause more sunlight to be absorbed by open water, which could accelerate warming.

Before summer sea ice disappears, Limoges is now co-leading research with Laval University’s Mathieu Ardyna to detail baseline conditions in the Lincoln Sea, which lies within the Last Ice Area.

On Monday, Limoges was slightly more than halfway through a month-long stint on the Amundsen icebreaker. The research cruise is currently on its third leg, for which Limoges is co-chief scientist along with Maxime Geoffroy, a research scientist from Memorial University.

Researchers from 14 different institutions are on board the ship, collecting samples and data for a variety of projects aimed at characterizing ecosystems in northern Baffin Bay, Nares Strait and the entrance to the Lincoln Sea.

On September 14, Limoges said the vessel reached 82°9’ North – where Nares Strait, the passage that separates Ellesmere Island and Greenland, spills out into the Lincoln Sea.

It’s the farthest north the Amundsen has ever been, Limoges said.

In the northern stretches of Nares Strait, environmental conditions are virtually undocumented.

“We are collecting samples in regions that have never been explored from a ship,” Limoges said.

For instance, she said, the crew had collected samples and data from Archer Fjord, an inlet on the northeast end of Ellesmere Island. Although previous aerial surveys had shown the area to be biologically productive, she said there is a dearth of information on the ecosystem.

“It’s very interesting and motivating to be part of the first research in such a northern region,” she said.

Navigating north

One of the reasons data on the Lincoln Sea is lacking is because it’s so hard to access.

According to Limoges, the Amundsen crew made it as far north as they did due to a combination of luck and planning.

The crew timed their expedition for mid-September, a time of year when Arctic sea ice – melting throughout the spring and summer – usually reaches a minimum.

Climate change also played a role in clearing the ship’s path. Summer sea ice cover is shrinking, and this year’s sea ice extent is on track to be the sixth-lowest on record, the New York Times reported.

On board the ship, Limoges said a team of sea ice specialists, members of the coast guard, and the Amundsen science crew looked for windows of opportunity to follow the sea ice safely.

“We had a whole team that was working together to make this cruise a success,” she said.

In addition to sea ice, the crew had to contend with winds that might push the ice around. Luckily, Limoges said, winds pushed sea ice to one side of Nares Strait, allowing the ship to navigate along the opposite side of the channel.

Along the way, Limoges described mountains along the coast, with iron oxides giving the rock a reddish tinge. She said crew members spotted polar bears, walruses and seals. The crew also lucked out with the weather, she said, with temperatures around freezing.

Limoges said getting to the entrance of the Lincoln Sea was “very impressive.”

“I think for a lot of people, it came with a lot of emotion,” she said. “We were really at the limit. We could see this wall of ice in front of us.”

At the edge of the Last Ice Area, Limoges said the team managed to do everything they had planned and more.

They collected water samples at different depths, measuring the samples’ temperature, salinity, nutrient and chemical content. They also mapped uncharted areas of the sea floor, used nets to sample plankton and fish, and collected sediment cores to get a glimpse of conditions further back in time.

In addition, the team anchored an instrument known as a mooring to the sea floor that will continue to collect data throughout the coming year.

After the researchers leave, Limoges said, moorings deployed at the entrance to the Lincoln Sea and elsewhere along the Amundsen’s path will gather information on salinity, temperature and sea ice, as well as collect particles sinking from the surface to the sea floor. The plan is to return next year to retrieve the moorings and access the data.

Although there is no shortage of work, Limoges said there are roughly 37 scientists and 40 crew members from the coast guard on the ship. When the vessel reaches a station, which can be any time of day or night, it’s all hands on deck.  

“Sometimes our day starts at 2am, sometimes it starts at 8am,” she said. “And then there are experiments running all the time.”

Although there is no such thing as a “normal day,” Limoges said, one thing is consistent: “You wake up with gorgeous landscapes, always.”

Years of work ahead

With a little more than a week left on the ship, the crew still has a lot of work ahead, Limoges said.  

On Monday, the icebreaker was entering Jones Sound, south of Ellesmere Island. Limoges said a community visit in Grise Fjord, Nunavut, was organized for Tuesday.

“The plan is to have people from the community come on board to visit the labs, to discuss what we are doing, and also to help us in the sampling operations in the fjord,” she said.

On October 5, the crew is scheduled to disembark in Resolute Bay. Once back home, the researchers will begin analyzing the samples they’ve collected. The goal is to get a sense of present-day conditions in the area as well as what the environment was like in the past – two key pieces of information that may help researchers better understand how the ecosystem may change in the future.

“It’s going to be years of work,” Limoges said. For her part, she said she intends to start by cutting sediment cores into slices and dating them to find out how deep in time they were able to sample.

For the next few days on the ship, research continues day and night.

Despite the odd hours, Limoges said she was feeling good. She added that collaboration among different research teams on the cruise has made the journey all the more interesting.

By looking at the ecosystem from different angles, she said, scientists will eventually be able to piece together a more coherent story of the area.