Ice that survived Arctic summer hits low, with implications for traditional harvesting and shipping | CBC News

A full-time harvester in Ulukhaktok, N.W.T, said ice should be forming around his home on Victoria Island this time of year — but instead, temperatures have been hovering around zero and it’s been raining. 

David Kuptana, a 64-year-old elder, said ice is forming later in the season and disappearing earlier — meaning it doesn’t get as thick in the winter. He’s worried about what that means for traditional harvesting, and about the long-term consequences the changing climate will have on caribou. 

The amount of sea ice that persists throughout the summer also affects how thick ice will grow in the Arctic in the winter. Ice that builds on an existing layer of ice can grow thicker than ice that grows seasonally from scratch.

Summer sea ice in the Arctic naturally shrinks in the summer. According to the National Snow and Ice Data Centre (NSIDC), Arctic summer sea ice dwindled to 4.23 million square kilometres on Sept. 19 — the sixth lowest extent on a 45-year record. 

That’s two million square kilometres smaller than average — a difference that’s about three times the size of Alberta. 

Mark Serreze, the director of the NSIDC in Boulder, Colorado, said this year’s minimum is part of a trend of shrinking Arctic ice that the centre has been observing for decades. By the mid 2040s, he said, one might look out across the Arctic in mid-September and see an all-blue ocean. 

‘Smooth sailing’ on Northwest Passage route

Dwindling summer sea ice is also changing how ships can travel through the Arctic.

The Canadian Ice Service posted on X that six per cent of the northern route through the Northwest Passage was covered in ice in late August. It’s the second-lowest ice coverage on record since 1968, after it dwindled to four per cent coverage in 2011, the organization said. 

Serreze said on the southern route, which has narrow channels and shallow water that make it less desirable for shipping, it would have been “smooth sailing this year.” On Tuesday, he said, it was still open with very little ice. 

Caribou drowning during migration

Arctic animals rely on certain ice features as habitats and sources of food. 

Seals, for example, look for rough ice and pressure ridges where they can give birth to their young, said Kuptana. Polar bears, in turn, hunt in those areas. 

Kuptana is worried how those ice features are going to change, and he fears for caribou that need the ice to grow thick in order to safely migrate between Victoria Island and the mainland. 

The Dolphin and Union caribou make that migration twice a year. The caribou were recently assessed as endangered — meaning extinction is imminent unless threats to the species can be mitigated. It’s now up to wildlife management authorities in the N.W.T. whether to uplist the caribou. They’re currently classified as being of “special concern” on the territory’s species at risk list.

One of the main factors in the assessment, according to the 2023 species status report, is climate change. Dangerous ice crossings and increased ship traffic are increasing the number of caribou that drown, while ice covering the snow makes it hard for them to access food. 

“It’s scary,” said Kuptana. “If the ice doesn’t freeze anymore and the ocean doesn’t freeze anymore, the caribou and the animals that used to migrate from the mainland to our island … they’re probably not going to migrate anymore.”