Brief communication: How deep is the snow on Mount Everest? The Cryosphere DOI 10.5194/tc-17-2625-2023 26 July 2023 There is very strong scientific and public interest regarding the snow thickness on Mountain Everest. Previously reported snow depths derived by different methods and instruments ranged from 0.92 to 3.5 m. Our measurements in 2022 provide the first clear radar image of the snowpack at the top of Mount Everest. The snow thickness at Earth’s summit was averaged to be 9.5 ± 1.2 m. This updated snow thickness is considerably deeper than values reported during the past 5 decades. Read more
Brief communication: Rapid ∼ 335 × 106 m3 bed erosion after detachment of the Sedongpu Glacier (Tibet) The Cryosphere DOI 10.5194/tc-17-2533-2023 17 July 2023 Following the detachment of the 130 × 10^6 m^3 Sedongpu Glacier (south-eastern Tibet) in 2018, the Sedongpu Valley underwent massive large-volume landscape changes. An enormous volume of in total around 330 × 10^6 m^3 was rapidly eroded, forming a new canyon of up to 300 m depth, 1 km width, and almost 4 km length. Such consequences of glacier change in mountains have so far not been considered at this magnitude and speed. Read more
Reversible ice sheet thinning in the Amundsen Sea Embayment during the Late Holocene The Cryosphere DOI 10.5194/tc-17-1787-2023 22 May 2023 Samples of bedrock recovered from below the West Antarctic Ice Sheet show that part of the ice sheet was thinner several thousand years ago than it is now and subsequently thickened. This is important because of concern that present ice thinning in this region may lead to rapid, irreversible sea level rise. The past episode of thinning at this site that took place in a similar, although not identical, climate was not irreversible; however, reversal required at least 3000 years to complete. Read more
Slowdown of Shirase Glacier, East Antarctica, caused by strengthening alongshore winds The Cryosphere DOI 10.5194/tc-17-445-2023 15 March 2023 Satellite observations have shown that the Shirase Glacier catchment in East Antarctica has been gaining mass over the past 2 decades, a trend largely attributed to increased snowfall. Our multi-decadal observations of Shirase Glacier show that ocean forcing has also contributed to some of this recent mass gain. This has been caused by strengthening easterly winds reducing the inflow of warm water underneath the Shirase ice tongue, causing the glacier to slow down and thicken. Read more
Improving interpretation of sea-level projections through a machine-learning-based local explanation approach The Cryosphere DOI 10.5194/tc-16-4637-2022 13 January 2023 To improve the interpretability of process-based projections of the sea-level contribution from land ice components, we apply the machine-learning-based “SHapley Additive exPlanations” approach to a subset of a multi-model ensemble study for the Greenland ice sheet. This allows us to quantify the influence of particular modelling decisions (related to numerical implementation, initial conditions, or parametrisation of ice-sheet processes) directly in terms of sea-level change contribution. Read more
The Antarctic contribution to 21st-century sea-level rise predicted by the UK Earth System Model with an interactive ice sheet The Cryosphere DOI 10.5194/tc-16-4053-2022 21 December 2022 The UK Earth System Model is the first to fully include interactions of the atmosphere and ocean with the Antarctic Ice Sheet. Under the low-greenhouse-gas SSP1–1.9 (Shared Socioeconomic Pathway) scenario, the ice sheet remains stable over the 21st century. Under the strong-greenhouse-gas SSP5–8.5 scenario, the model predicts strong increases in melting of large ice shelves and snow accumulation on the surface. The dominance of accumulation leads to a sea level fall at the end of the century. Read more
The impact of climate oscillations on the surface energy budget over the Greenland Ice Sheet in a changing climate The Cryosphere DOI 10.5194/tc-16-3375-2022 14 November 2022 To overcome internal climate variability, this study uses k-means clustering to combine NAO, GBI and IWV over the Greenland Ice Sheet (GrIS) and names the approach as the North Atlantic influence on Greenland (NAG). With the support of a polar-adapted RCM, spatio-temporal changes on SEB components within NAG phases are investigated. We report atmospheric warming and moistening across all NAG phases as well as large-scale and regional-scale contributions to GrIS mass loss and their interactions. Read more
TermPicks: a century of Greenland glacier terminus data for use in scientific and machine learning applications The Cryosphere DOI 10.5194/tc-16-3215-2022 7 November 2022 Terminus traces have been used to understand how Greenland’s glaciers have changed over time; however, manual digitization is time-intensive, and a lack of coordination leads to duplication of efforts. We have compiled a dataset of over 39 000 terminus traces for 278 glaciers for scientific and machine learning applications. We also provide an overview of an updated version of the Google Earth Engine Digitization Tool (GEEDiT), which has been developed specifically for the Greenland Ice Sheet. Read more
A probabilistic framework for quantifying the role of anthropogenic climate change in marine-terminating glacier retreats The Cryosphere DOI 10.5194/tc-16-2725-2022 17 October 2022 Marine-terminating glaciers have recently retreated dramatically, but the role of anthropogenic forcing remains uncertain. We use idealized model simulations to develop a framework for assessing the probability of rapid retreat in the context of natural climate variability. Our analyses show that century-scale anthropogenic trends can substantially increase the probability of retreats. This provides a roadmap for future work to formally assess the role of human activity in recent glacier change. Read more
Clouds drive differences in future surface melt over the Antarctic ice shelves The Cryosphere DOI 10.5194/tc-16-2655-2022 3 October 2022 Model projections suggest large differences in future Antarctic surface melting even for similar greenhouse gas scenarios and warming rates. We show that clouds containing a larger amount of liquid water lead to stronger melt. As surface melt can trigger the collapse of the ice shelves (the safety band of the Antarctic Ice Sheet), clouds could be a major source of uncertainties in projections of sea level rise. Read more