Last Ice Area research reveals new vulnerability to Arctic warming
As sea ice continues to disappear, the Arctic is expected to be ice-free during the summer months by mid-century, except for one place. This exception, known as the Last Ice Area (LIA), is a region in the high Arctic, above Canada and Greenland, that is projected to be the final refuge for summer sea ice as the planet warms.
It will be a critical stronghold for ice-dependent marine species that rely on sea ice for survival, as it will persist longer than elsewhere in the Arctic. However, new high-resolution climate research reveals that this enduring sanctuary may be more vulnerable than previously thought.

We explore the study’s key findings and their implications in a conversation with one of its authors, Bruno Tremblay, a professor at McGill University.
In the study, the sea ice in the Last Ice Area will thin and become more mobile, under high greenhouse gas emissions, with increased ice export through Arctic channels like the Nares Strait and the Canadian Arctic Archipelago. Advanced modeling predicts ice export will double compared to the 1990s, depleting ice reserves faster than anticipated.
Earlier models underestimated the impact of dynamic ice movement, but here, future scenarios predict that thinner, weaker ice will be more easily transported. The thick, multi-year ice in the LIA is projected to thin significantly and lose its stability about a decade after the Arctic becomes seasonally ice-free under a high greenhouse gas emissions scenario, where continued warming drives substantial changes to this critical ice reserve.
Why will the ice in the Last Ice Area become thinner and more mobile?
The long-term thinning of Arctic sea ice, including in the Last Ice Area, is driven by a warming climate caused by increased greenhouse gas emissions. Reduced ice formation during winter, combined with increased open water and ice melt in summer, contributes to this decline. Thinner ice is mechanically weaker, causing the ice pack to drift faster under the same surface winds and ocean currents. Additionally, climate projections suggest stronger winds throughout the 21st century, which are expected to further exacerbate the effects of ice thinning.

Your study suggests the Last Ice Area may transition from being a refuge for multi-year sea ice to a seasonally ice-free system approximately 10 years after the Arctic loses its summer ice. What would you envision the region looking like at that point? And what factors could accelerate or delay this transition?
Our study indicates that the last one million square kilometres of sea ice (what is considered a seasonally ice-free Arctic) could be drained through the archipelago in just over a decade. During this transition, the LIA and the Arctic Ocean will experience significant changes. There will be an increase in the area covered by smoother first-year ice rather than older, possibly thicker, ridged ice. Additionally, the formation of a stable landfast ice cover will be delayed, with potential winter break-up events during high wind conditions.
In summer, the dismantling of the stable winter pack ice is projected to occur earlier and at a faster rate. Using the same high-resolution Community Earth System Model, the projected seasonality of the sea ice in the LIA, will be the subject of a follow-up study. Curbing carbon dioxide emissions would delay Arctic warming and the loss of the LIA. Natural (and inherently unpredictable) variability could also delay or advance the transition to an ice-free LIA by approximately a decade.
Other factors further complicate this picture. For instance, North American forest fires south of the Arctic produce aerosols that are carried northward, making the clouds more reflective and reducing the summer sea ice melt in the Arctic. At the same time, low summer sea ice extent in the Arctic promotes hotter, drier conditions in southern North America, which exacerbates wildfires, suggesting a complex feedback in the system. Strong late-summer storms provide another example: these Arctic storms disperse the pack ice, allowing more sunshine to penetrate the ocean surface and increase melt. These impacts are even more pronounced when they follow an anomalously warm winter that results in thinner pack ice at the onset of the melt season.
All in all, the timing of this transition depends on a combination of known factors, such as Arctic warming and other variables that are harder to predict. The interplay of these processes underscores the complexity of the Arctic system and the challenges in projecting its future state.

What do your findings suggest about the future of the Arctic as we know it? Based on your research, what steps could governments, communities, or industries take to slow the sea ice loss in the Last Ice Area and safeguard its role as a refuge for multi-year sea ice?
The study’s results suggest that seasonally ice-free conditions in the Arctic and LIA will occur earlier than previously believed. These changes are linked to shifts in marine ecosystems, impacts on permafrost in surrounding frozen soils, reduced summer surface albedo contributing to increased warming, increased wave action on sea ice cover and coastal areas, and accelerated soil erosion. To address these challenges, governments can implement regulations to reduce the burning of fossil fuels and promote the adoption of renewable energy sources. Despite these changes, communities remain resilient and will adapt to the changing ice-scape.
About the study
Revisiting the Last Ice Area Projections from a High-Resolution Global Earth System Model by Madeleine Fol, Bruno Tremblay, McGill University, Stephanie Pfirman, Arizona State University, Robert Newton, Columbia University, Stephen Howell, and Jean-François Lemieux, Environment and Climate Change Canada.
This article originally appeared on WWF’s Global Arctic Programme.