In Antarctica, ocean tides control the motion of ice sheets near the coastline as well as melt rates underneath the floating ice. By combining the spatial advantage of rare but highly accurate satellite images with the temporal advantage of tide-prediction models, vertical displacement of floating ice due to ocean tides can now be predicted accurately. This allows the detailed study of ice-flow dynamics in areas that matter the most to the stability of Antarctica's ice sheets.

We evaluate a downscaling method to calculate ice sheet surface mass balance with global climate models, despite their coarse resolution. We compare it with high-resolution climate modeling. Despite absence of fine-scale simulation of individual energy and mass contributors, the method provides realistic vertical SMB gradients that can be used in forcing of ice sheet models, e.g., for sea level projections. Also, the climate model simulation is improved with the method implemented interactively.

Sea ice volume export through the Fram Strait has been studied using varied methods, however, mostly in winter months. Here we report sea ice volume estimates that extend over summer seasons. A recent developed sea ice thickness dataset, in which CryoSat-2 and SMOS sea ice thickness together with SSMI/SSMIS sea ice concentration are assimilated, is used and evaluated in the paper. Results show our estimate is more reasonable than that calculated by satellite data only.

We manually map 18 737 avalanche outlines based on SPOT6 optical satellite imagery acquired in January 2018. This is the most complete and accurate avalanche documentation of a large avalanche period covering a big part of the Swiss Alps. This unique dataset can be applied for the validation of other remote-sensing-based avalanche-mapping procedures and for updating avalanche databases to improve hazard maps.

Snow surfaces, under the action of wind, form beautiful shapes such as waves and dunes. This study is the first ever study to simulate these shapes using a state-of-the-art numerical modelling tool. While these beautiful and ephemeral shapes on snow surfaces are fascinating from a purely aesthetic point of view, they are also critical in regulating the transfer of heat and mass between the atmosphere and snowpacks, thus being of huge importance to the Earth system.

A systematic evaluation of 10 global satellite data products of the polar sea-ice area is performed. Inter-product differences in evaluation results call for careful consideration of data product limitations when performing sea-ice area trend analyses and for further mitigation of the effects of sensor changes. We open a discussion about evaluation strategies for such data products near-0 % and near-100 % sea-ice concentration, e.g. with the aim to improve high-concentration evaluation accuracy.

The meltwater scavenging coefficient (MSC) determines the BC enrichment in the surface layer of melting snow and therefore modulates the BC-snow-albedo feedbacks. This study presents a new method for MSC estimation over the sea-ice area in Arctic. Using this new method, we analyze the spatial variability of MSC in the western Arctic and demonstrate that the value in Canada Basin (23.6 % ± 2.1 %) ≈ that in Greenland (23.0 % ± 12.5 %) > that in Chukchi Sea (17.9 % ± 5.0 %) > that in Elson Lagoon (14.5 % ± 2.6 %).

To provide estimates of past glacier mass changes, an adequate initial state is required. However, information about past glacier states at regional or global scales is largely incomplete. Our study presents a new way to initialize the Open Global Glacier Model from past climate information and present-day geometries. We show that even with perfectly known but incomplete boundary conditions, the problem of model initialization leads to nonunique solutions, and we propose an ensemble approach.

We investigate the changing character of runoff, river discharge and other hydrological elements across watershed draining the North Slope of Alaska over the period 1981–2010. Our synthesis of observations and modeling reveals significant increases in the proportion of subsurface runoff and cold season discharge. These and other changes we describe are consistent with warming and thawing permafrost, and have implications for water, carbon and nutrient cycling in coastal environments.

Information on snow stability is important for avalanche forecasting. To improve the stability estimation in the snow cover model SNOWPACK, we suggested an improved parameterization for the critical crack length. We compared 3 years of field data to SNOWPACK simulations. The match between observed and modeled critical crack lengths greatly improved, and critical weak layers appear more prominently in the modeled vertical profile of critical crack length.

Climate change is devastating winter tourism. High-elevation, high-latitude ski centers have turned to saving snow over the summer. We present results of two field seasons to test and optimize over-summer snow storage at a midlatitude, low-elevation nordic ski center in the northeastern USA. In 2018, we tested coverings and found success overlaying 20 cm of wet woodchips with a reflective sheet. In 2019, we employed this strategy to a large pile and stored sufficient snow to open the ski season.

Understanding gas trapping in polar ice is essential to study the relationship between greenhouse gases and past climates. New data of bubble closure, used in a simple gas-trapping model, show inconsistency with the final air content in ice. This suggests gas trapping is not fully understood. We also use a combination of high-resolution measurements to investigate the effect of polar snow stratification on gas trapping and find that all strata have similar pores, but that some close in advance.

Snow mass fluxes and vertical profiles of relative humidity are used to document concurrent occurrences of drifting snow and near-surface air saturation at a site dominated by katabatic winds in East Antarctica. Despite a high prevalence of drifting snow conditions, we demonstrate that saturation is reached only in the most extreme wind and transport conditions and discuss implications for the understanding of surface mass and atmospheric moisture budgets of the Antarctic ice sheet.

The snow water equivalent (SWE) in high mountain regions is crucial for many applications. Yet its quantification remains difficult. We present autonomous daily SWE observations by a cosmic ray sensor (CRS) deployed on a Swiss glacier for two winter seasons. Combined with snow depth observations, we derive the daily bulk snow density. The validation with manual field observations and its measurement reliability show that the CRS is a promising device for high alpine cryospheric environments.