As climate change reduces the size and duration of summer Arctic sea ice, scientific projections show it will last the longest above Canada and Greenland. This is the Last Ice Area.

Arctic sea ice goes through a seasonal cycle each year. It grows and spreads across the Arctic Ocean through northern fall and winter, even pushing into the North Atlantic and North Pacific by the time it reaches its maximum in February or March. Currently, nearly three-quarters of this sea ice is seasonal, meaning that it melts away through the spring and summer. The portion that survives the melt season is called year-round sea ice.

Source: NASA/Goddard Space Flight Center’s Scientific Visualization Studio. The Blue Marble data is courtesy of Reto Stockli (NASA/GSFC).

Satellites have provided a reliable tool for continuously monitoring changes in the Arctic ice since 1979. Every summer, the Arctic ice cap melts to what scientists call its ”minimum” before colder weather begins to make ice cover increase. This visualization shows the expanse of the annual minimum Arctic sea ice for each year from 1979 through 2022. You can see how the area with the most ice cover corresponds to the Last Ice Area, shown in the map above. 

Why is the Last ice area Important?

Sea ice serves many purposes in the Arctic:

• Polar bears, walrus and certain species of seals need sea ice to feed, reproduce and rest. The Arctic sea ice ecosystems are complex and interconnected, supporting a wide variety of life. 
• Indigenous peoples use Arctic sea ice as a platform for important subsistence hunting activities which in turn maintains cultural heritage and traditional practices.
• The Arctic sea ice supports tourism, and other industries that contribute to the economy of the region and provide livelihoods for local communities.
• Multi-year sea ice slows the warming of the Arctic reflect sunlight, cooling the region. But as ice melts, darker surfaces absorb more heat, exacerbating climate change.
• The presence of sea ice serves to diminish wind and wave activity, thereby mitigating coastal erosion.
• Multi-year sea ice is far more effective than first-year sea ice at minimizing underwater noise from shipping, for example, as it can absorb and dampen sound more effectively compared to thinner and more porous first-year ice.

About a quarter of the world’s polar bears live in the LIA or near there. Most of the world’s narwhals spend at least part of the year there, and it is home to the largest breeding colonies of thick-billed murres and millions of little auks. Small but vitally important algae, the tiny engines driving the Arctic food web, turn the underside of the sea ice into a kind of hanging garden where shrimp-like creatures graze. The ice algae eventually drift downward and provide nourishment on the ocean floor. There are even organisms here that only thrive on multi-year ice – for these lifeforms the Last Ice Area may be their last chance for survival.

How long will the multiyear sea ice last in the Last Ice Area?

Arctic sea ice has seen significant declines since satellite observations began in 1978, and this trend is expected to continue. By the 2020s or 2030s, it’s projected that the Arctic may experience ice-free conditions, regardless of efforts to reduce emissions. The loss of sea ice will likely begin in specific regions before spreading throughout the Arctic, including the LIA, impacting not just September but also August and October as temperatures rise.

If warming continues even the Last Ice Area will vanish for months out of the year causing a devastating loss of habitat and accelerating the climate crisis. New research reveals that the Last Ice Area (LIA) has disappeared during the summer months in the past and it will do so again, perhaps sooner than we think.

The total impact of these environmental changes on Arctic ecosystems remains uncertain, but it is undeniable that the species that depend on sea ice—from small ice algae to polar cod, seals and polar bears—will face significant challenges. Their future is likely to be found here, in the LIA.