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1. Revisiting the Last Ice Area projections from a high-resolution Global Earth System Model

   https://doi.org/10.1038/s43247-025-02034-5  

   Fol, Madeleine; Tremblay, Bruno; Pfirman, Stephanie; Newton, Robert; Howell, Stephen; Lemieux, Jean-François (December 2025, Communications Earth & Environment)

   Abstract The Last Ice Area—located to the north of Greenland and the northern Canadian Arctic Archipelago—is expected to persist as the central Arctic Ocean becomes seasonally ice-free within a few decades. Projections of the Last Ice Area, however, have come from relatively low resolution Global Climate Models that do not resolve sea ice export through the waterways of the Canadian Arctic Archipelago and Nares Strait. Here we revisit Last Ice Area projections using high-resolution numerical simulations from the Community Earth System Model, which resolves these narrow waterways. Under a high-end forcing scenario, the sea ice of the Last Ice Area thins and becomes more mobile, resulting in a large export southward. Under this potentially worst-case scenario, sea ice of the Last Ice Area could disappear a little more than one decade after the central Arctic Ocean has reached seasonally ice-free conditions. This loss would have profound impacts on ice-obligate species. 

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2. Competing processes determine the long-term impact of basal friction parameterizations for Antarctic mass loss

   https://doi.org/10.5194/tc-20-1217-2026  

   van_den_Akker, Tim; Lipscomb, William H; Leguy, Gunter R; van_de_Berg, Willem Jan; van_de_Wal, Roderik_S W (February 2026, The Cryosphere)

   Previous studies do not agree on the magnitude of the influence of basal friction laws in sea-level projections. We use the Community Ice Sheet Model (CISM) to show that the sensitivity of the projected sea level rise to the choice of basal friction law depends on the specific geometric setting and the initial state of the ice sheet model. We find a geometry-driven connection between buttressing and basal sliding in the Amundsen Sea Embayment when performing multi-century future simulations based on the present-day observed imbalance of the Antarctic Ice Sheet, in which Thwaites and Pine Island glaciers eventually collapse. We perform two initializations which differ in their value of a free parameter that governs the effective pressure of ice grounded on bedrock below sea level. Both initializations lead to a modelled Antarctic Ice Sheet that well resembles present-day conditions (ice thickness, ice surface velocities and mass changes rates). Following each initialization, we run the model forward with present-day climate forcing. In one simulation, Thwaites Glacier collapses first, and in the other, Pine Island Glacier collapses first. When Thwaites Glacier collapses first, it creates a grounding line flux large enough to sustain an ice shelf that provides buttressing which largely balances the basal friction differences when using different basal friction parameterizations. A collapsing Pine Island Glacier, however, is sensitive to the choice of basal friction law. Thus, the regional evolution and its sensitivity to friction laws depend on initialization choices that are poorly constrained by observations. In both simulations, present-day ocean thermal forcing, which is a product of the inversion using the present-day imbalance, is sufficient to drive Thwaites and Pine Island collapse, but small differences introduce an uncertainty of about 500 years in the collapse timing. 

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3. Historical Volcanic Eruptions Mitigated the Expected Rapid Arctic Sea Ice Decline Prior to 2000

   https://doi.org/10.1029/2026GL123968  

   Wang, Xinyue; Liu, Fei; Dong, Wenjie; Ding, Qinghua (June 2026, Geophysical Research Letters)

   Abstract Arctic sea ice has declined at sharply contrasting rates over the past four decades—modest before 2000 and rapid thereafter. Using observational and model evidence, we show that large tropical volcanic eruptions can trigger decade‐long Arctic sea ice recoveries, and that without the 1982 El Chichón and 1991 Pinatubo eruptions, Arctic sea ice would have declined approximately 1.5 times faster before 2000. We further show a model's sensitivity to volcanic aerosol forcing scales with its sensitivity to GHG forcing across CMIP6 models, offering a new strategy to identify models with realistic climate response to radiative forcing. Following this, a selected subgroup of models that accurately simulate long‐term warming trend and decade‐long post‐Pinatubo recovery project ice‐free Arctic summer up to 20 years earlier than the full ensemble. These findings underscore the critical, yet underappreciated, importance of evaluating climate models against anthropogenic and volcanic forcing when projecting the future of Arctic sea ice. 

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4. Arctic Sea Ice Loss Weakens Northern Hemisphere Summertime Storminess but Not Until the Late 21st Century

   https://doi.org/10.1029/2022GL102301  

   Kang, Joonsuk M; Shaw, Tiffany A; Sun, Lantao (May 2023, Geophysical Research Letters)

   Abstract Observations show Arctic sea ice has declined and midlatitude storminess has weakened during Northern Hemisphere (NH) summertime. It is currently unclear whether Arctic sea ice loss impacts summertime storminess because most previous work focuses on other seasons. Here we quantify the impact of Arctic sea ice loss on NH summertime storminess using equilibrium and transient climate model simulations. The equilibrium simulations show mid‐to‐late 21st century Arctic sea ice loss weakens summertime storminess, but only in the presence of ocean coupling. With ocean coupling, the equator‐to‐pole temperature and atmospheric energy gradients significantly weaken due to increased surface turbulent flux in the polar region following Arctic sea ice loss. The transient simulations show Arctic sea ice loss does not significantly weaken summertime storminess until the late 21st century. Furthermore, Arctic Amplification, which is dominated by Arctic sea ice loss in the present day, does not significantly impact the present‐day weakening of summertime storminess. 

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5. Evolution of sediment temperature, pressure, phases distribution, carbon pools and seabed methane flux at the Arctic continental Shelves since the Last Glacial Maximum

   https://doi.org/10.5281/zenodo.8428754  

   You, Kehua (January 2023, Zenodo)

   This dataset are produced by a manuscript (Biodegradation of Ancient Organic Carbon Fuels Seabed Methane Emission at the Arctic Continental Shelves)  to be submitted to the Journal of Geophysical Research - Global Biogeochemical Cycles.  I The file "MethaneEmission_Permafrost" contains the predicted  temperature, pressure, pore water salinity, ice stable zone, methane hydrate stable zone, ice saturation, methane hydrate saturation, free methane gas saturation, labile organic carbon content, stable organic carbon content, and methanogenesis rate from seafloor to 1200 m depth from 18,000 years before present to 2,000 years after present for 8 different simulation scenarios.  The file "Seabed_Methane_Flux" contains the predicted seabed methane emission rate from 18,000 years before present to 2,000 years after present for 8 different simulation scenarios.  Detailed information about the model could be found in the paper Biodegradation of Ancient Organic Carbon Fuels Seabed Methane Emission at the Arctic Continental Shelves.    

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