Speed-up, slowdown, and redirection of ice flow on neighbouring ice streams in the Pope, Smith, and Kohler region of West Antarctica The Cryosphere DOI 10.5194/tc-19-1725-2025 8 May 2025 We used satellite observations to measure recent changes in ice speed and flow direction in the Pope, Smith, and Kohler region of West Antarctica (2005–2022). We found substantial speed-up on seven ice streams of up to 87 %. However, Kohler West Glacier has slowed by 10 %, due to the redirection of ice flow into its rapidly thinning neighbour. This process of “ice piracy” has not previously been directly observed on this rapid timescale and may influence future ice shelf and sheet mass changes. Read more
The system of atmosphere, land, ice and ocean in the region near the 79N Glacier in northeast Greenland: synthesis and key findings from the Greenland Ice Sheet–Ocean Interaction (GROCE) experiment The Cryosphere DOI 10.5194/tc-19-1789-2025 8 May 2025 The Greenland Ice Sheet represents the second-largest contributor to global sea-level rise. We quantify atmosphere, ice and ocean processes related to the mass balance of glaciers in northeast Greenland, focusing on Greenland’s largest floating ice tongue, the 79° N Glacier. We find that together, the different in situ and remote sensing observations and model simulations reveal a consistent picture of a coupled atmosphere–ice sheet–ocean system that has entered a phase of major change. Read more
Inter-model differences in 21st century glacier runoff for the world's major river basins The Cryosphere DOI 10.5194/tc-19-1491-2025 8 April 2025 Glacier models have historically been used to understand glacier melt’s contribution to sea level rise. The capacity to project seasonal glacier runoff is a relatively recent development for these models. In this study we provide the first model intercomparison of runoff projections for the glacier evolution models capable of simulating future runoff globally. We compare model projections from 2000 to 2100 for all major river basins larger than 3000 km2 with over 30 km2 of initial glacier cover. Read more
The glaciers of the Dolomites: the last 40 years of melting The Cryosphere DOI 10.5194/tc-19-1335-2025 26 March 2025 We have reconstructed the multi-decadal (1980s–2023) ice mass changes for all the current mountain glaciers in the Dolomites. We used historical aerial photographs, drone surveys, and lidar to fill the glaciological data gap for the region. We observed an alarming decline in both glacier area and volume, with some of the glaciers showing smaller losses due to local topography and debris cover feedback. We strongly recommend more specific monitoring of these glaciers. Read more
Brief communication: Sea-level projections, adaptation planning, and actionable science The Cryosphere DOI 10.5194/tc-19-793-2025 25 February 2025 As communities try to adapt to climate change, they look for “actionable science” that can inform decision-making. There are risks in relying on novel results that are not yet accepted by the science community. We propose a practical criterion for determining which scientific claims are actionable. We show how premature acceptance of sea-level-rise predictions can lead to confusion and backtracking, and we suggest best practices for communication between scientists and adaptation planners. Read more
Present-day mass loss rates are a precursor for West Antarctic Ice Sheet collapse The Cryosphere DOI 10.5194/tc-19-283-2025 29 January 2025 In this study, we present an improved way of representing ice thickness change rates in an ice sheet model. We apply this method using two ice sheet models of the Antarctic Ice Sheet. We found that the two largest outlet glaciers on the Antarctic Ice Sheet, Thwaites Glacier and Pine Island Glacier, will collapse without further warming on a timescale of centuries. This would cause a sea level rise of about 1.2 m globally. Read more
A topographically controlled tipping point for complete Greenland ice sheet melt The Cryosphere DOI 10.5194/tc-19-63-2025 13 January 2025 Anthropogenic warming is causing accelerated Greenland ice sheet melt. Here, we use a computer model to understand how prolonged warming and ice melt could threaten ice sheet stability. We find a threshold beyond which Greenland will lose more than 80 % of its ice over several thousand years, due to the interaction of surface and solid-Earth processes. Nearly complete Greenland ice sheet melt occurs when the ice margin disconnects from a region of high elevation in western Greenland. Read more
Twenty-first century global glacier evolution under CMIP6 scenarios and the role of glacier-specific observations The Cryosphere DOI 10.5194/tc-18-5045-2024 18 November 2024 Glaciers are major contributors to sea-level rise and act as key water resources. Here, we model the global evolution of glaciers under the latest generation of climate scenarios. We show that the type of observations used for model calibration can strongly affect the projections at the local scale. Our newly projected 21st century global mass loss is higher than the current community estimate as reported in the latest Intergovernmental Panel on Climate Change (IPCC) report. Read more
Ice viscosity governs hydraulic fracture that causes rapid drainage of supraglacial lakes The Cryosphere DOI 10.5194/tc-18-3991-2024 6 September 2024 Due to surface melting, meltwater lakes seasonally form on the surface of glaciers. These lakes drive hydrofractures that rapidly transfer water to the base of ice sheets. This paper presents a computational method to capture the complicated hydrofracturing process. Our work reveals that viscous ice rheology has a great influence on the short-term propagation of fractures, enabling fast lake drainage, whereas thermal effects (frictional heating, conduction, and freezing) have little influence. Read more
Coupled ice–ocean interactions during future retreat of West Antarctic ice streams in the Amundsen Sea sector The Cryosphere DOI 10.5194/tc-18-2653-2024 15 July 2024 A new ice–ocean model simulates future ice sheet evolution in the Amundsen Sea sector of Antarctica. Substantial ice retreat is simulated in all scenarios, with some retreat still occurring even with no future ocean melting. The future of small “pinning points” (islands of ice that contact the seabed) is an important control on this retreat. Ocean melting is crucial in causing these features to go afloat, providing the link by which climate change may affect this sector’s sea level contribution. Read more