Work

Modeling the 21st-century response of Greenland's Zachariæ Isstrøm and Nioghalvfjerdsfjorden glaciers to atmosphere–ocean forcing and friction laws

Year: 2025

Type: article

Abstract: Recent rapid retreat of outlet glaciers in Northeast Greenland has raised concerns over their future stability and sea-level-rise potential. However, large uncertainties remain in long-term projections due to limited constraints on basal friction and external forcings. Here, we use the Ice Sheet System Model (ISSM) to simulate the century-scale evolution (2018–2100) of Zachariæ Isstrøm (ZI) and Nioghalvfjerdsfjorden (79N) glaciers under a suite of atmosphere–ocean forcing scenarios, with a systematic evaluation of how different basal friction laws and parameterizations influence ice-dynamic responses. ZI Glacier exhibits limited retreat (20–25 km) under the most extreme ocean forcing (frontal melt = 6 m/d; basal melt = 90–0 m per year from 450 to 100 m b.s.l.) and remains pinned on a subglacial ridge about 25 km inland from its 2018 terminus, even under the strongest climate scenarios (MIROC5_RCP8.5, MPI-ESM_SSP5-8.5). By contrast, 79N Glacier experiences more sustained ice-shelf thinning and grounding-line retreat, with local thickness reductions approaching 200 m in some experiments. Both frontal sides of the 79N ice shelf show partial detachment even under low-emission scenarios (MIROC5_RCP2.6, MPI-ESM_SSP1-2.6), indicating an elevated risk of structural collapse. Among the tested forcings, atmospheric warming produces the largest total ice-mass loss, yielding a combined sea-level contribution of ∼3 mm by 2100 under high-emission scenarios, while ocean thermal forcing and basal friction exert comparatively smaller effects. Despite this dominant atmospheric influence, our results highlight that grounding-zone basal conditions critically modulate glacier sensitivity and remain a major source of uncertainty in Greenland's sea-level-rise projections.

Source: Advances in Climate Change Research

DOI: 10.1016/j.accre.2025.11.006

Authors: Yu-Ting Dong, Hai-Yang Zhu, Teng Li, Ji Zhao, Chang-Liang Shao

Institutions: China University of Geosciences, Sun Yat-sen University, Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), China Meteorological Administration

Language: English

Topic: Cryospheric studies and observations

Subfield: Atmospheric Science

Field: Earth and Planetary Sciences

Domain: Physical Sciences

SDG: Climate action

Open Access status: gold

Estimated APC paid: $2,000