A numerical model is used to investigate how Antarctic sea ice concentration and volume are affected by increased melting caused by ocean-wave breakup of the ice. When temperatures are high enough to melt the ice, concentration and volume are reduced for ~ 100 km into the ice-covered ocean. When temperatures are low enough for ice growth, the concentration recovers, but the reduced volume persists.

We use surface height data from west Greenland and Devon Ice Cap to check the performance of the new interferometric mode of the ESA CryoSat radar altimeter. The detailed height comparison allows an improved system calibration and processing methodology and measurement of the height of supraglacial lakes which form each summer around the periphery of the Greenland Ice Cap. The advantages of the SARIn mode suggest that future satellite radar altimeters for glacial ice should use this technology.

Previous research has paid significant attention to permafrost, e.g. active layer thickness, soil temperature, area extent, and associated degradation leading to other changes. However, less focus has been given to seasonally frozen ground and vast area extent. We combined data from more than 800 observation stations, as well as gridded data, to investigate soil freeze depth across China. The results indicate that soil freeze depth decreases with climate warming.

This study contributes to investigations of the effect of impurities on ice microstructure and flow properties. For the first time we mapped over 5000 micro-inclusions in four samples from the EDML and NEEM polar ice cores. The particle distributions show no correlation with grain boundaries and thus we conclude that particle pinning plays only a secondary role for the microstructure evolution. Alternative mechanisms are discussed.

Snow spectral albedo in the visible/near-infrared range has been continuously measured during a winter season at Col de Porte alpine site (French Alps; 45.30° N, 5.77°E; 1325 m a.s.l.). This study highlights that the variations of spectral albedo can be successfully explained by variations of the following snow surface variables: snow-specific surface area, effective light-absorbing impurities content, presence of liquid water and slope.

The paper describes the processing of kinematic GNSS data observed over nine seasons in East Antarctica. The obtained surface elevation profiles are used to validate several data sets of satellite altimetry. Thus, we find a clear recommendation that processing versions provide the highest accuracy and precision. The profiles are used to derive a new set of ICESat laser campaign biases and finally, to evaluate several DEMs.

At a major outlet of the Greenland Ice Sheet in West Greenland, we find that the chemical solutes in the emerging subglacial waters are out of phase with water discharge and can spike in concentration during waning flow. This suggests that the subglacial waters are spreading out across a large area of the glacial bed throughout the day, stimulating chemical weathering beyond the major water distribution channels.

How could plant life, that needs light to survive, live on a planet covered with ice? Such a situation is thought to have existed during what are called the Snowball Earth events over 600 million years ago. Here we find that ice shadows, regions where ice has difficulty flowing into, may have a played a role in that survival of early plant life.

During summer, a large portion of sea ice in the Arctic is typically covered with meltwater. We present a simple model for the evolution of melt ponds on permeable sea ice that both fits observations and allows us to understand the behavior of melt ponds in a way that is often not possible with more complex models. We use this model to show that pond coverage will increase under global warming. This work is important as melt ponds affect the overall reflectance of sea ice.

Physically based multilayer snowpack models suffer from various modelling errors. To represent these errors, we built the new multiphysical ensemble system ESCROC by implementing new representations of different physical processes in a coupled multilayer ground/snowpack model. This system is a promising tool to integrate snow modelling errors in ensemble forecasting and ensemble assimilation systems in support of avalanche hazard forecasting and other snowpack modelling applications.

We conducted a large field campaign to collect snow samples in Xinjiang. We measured insoluble light-absorbing particles with estimated black carbon concentrations of 10–150 ng^g-1. We found a probable shift in emission sources with the progression of winter and dominated contributions of BC and OC to light absorption. A PMF model indicated an optimal three-factor/source solution that included industrial pollution, biomass burning, and soil dust.

Using radio-echo sounding data from northern Greenland, we demonstrate that subglacial roughness exhibits self-affine (fractal) scaling behaviour. This enables us to assess topographic control upon the bed-echo waveform, and explain the spatial distribution of the degree of scattering (specular and diffuse reflections). Via comparison with a prediction for the basal thermal state (thawed and frozen regions of the bed) we discuss the consequences of our study for basal water discrimination.

We reconstruct the Holocene development of the Zackenberg River delta (northeast Greenland) using a combination of sedimentology, cryostratigraphy, and geochronology. We distinguish four major depositional environments and identify three cryofacies. We apply the principles of cryostratigraphy to infer the aggradational history of permafrost. This paper contains an archive of ground ice in epigenetic permafrost in northeast Greenland.

We combine 2-D ice flow model with linear elastic fracture mechanics (LEFM) to model the calving behavior of Thwaites Glacier, West Antarctica. We find the combination of full-Stokes (FS) model and LEFM produces crevasses that are consistent with observations. We also find that calving is enhanced with pre-existing surface crevasses, shorter ice shelves or undercut at the ice shelf front. We conclude that the FS/LEFM combination is capable of constraining crevasse formation and iceberg calving.

In our study we combined the wealth of information provided by Greenland ice cores with an ultra-high-resolution technique well known in geoscience (laser ablation). Our set-up was developed and applied to investigate the variability in concentration of ions across a rapid climatic change from the oldest part of the last glaciation, showing that concentrations drop abruptly from cold to warm periods, representing a shift in atmospheric transport that happens even faster than previously thought.

Talus slopes are a widespread geomorphic feature, which may show permafrost conditions even at low elevation due to cold microclimates induced by a gravity-driven internal air circulation. We show for the first time a numerical simulation of this internal air circulation of a field-scale talus slope. Results indicate that convective heat transfer leads to a pronounced ground cooling in the lower part of the talus slope favoring the persistence of permafrost.

The reduction of ice masses stored on land has made an important contribution to sea-level rise over the last century, as well as changed the Earth's shape. We model the solid-earth response to ice mass changes and find significant vertical deformation signals over large continental areas. We show how deformation rates have varied strongly throughout the last century, which affects the interpretation and extrapolation of recent observations of vertical land motion and sea-level change.

Vast Arctic methane deposits may alter global climate and require remote sensing (RS) to map. Sonar has great promise, but quantitative inversion based on theory is challenged by multiple bubble acoustical scattering in plumes. We demonstrate use of a real-world in situ bubble plume calibration using a bubble model to correct for differences in the calibration and seep plumes. Spatial seep sonar maps were then used to improve understanding of subsurface geologic controls.

This study presents data from Mont Jacques-Cartier, the highest summit in the Appalachians of south-eastern Canada, to demonstrate that the occurrence of contemporary permafrost body is associated with a very thin and wind-packed winter snow cover which brings local azonal topo-climatic conditions on the dome-shaped summit. This study is an important preliminary step in modelling the regional spatial distribution of permafrost on the highest summits in eastern North America.

The Greenland ice sheet melts faster in a warmer climate. The ice sheet is flatter at high elevation, therefore atmospheric warming increases the melt area exponentially. For current climate conditions, we find that the ice sheet shape amplifies the total meltwater generation by roughly 60 %. Meltwater is not stored underneath the ice sheet, as previously found, but it does take multiple days for it to pass through the seasonally developing subglacial drainage channels, moderating discharge.

Since the Antarctic sea ice extent shows a recent increase, we investigate the sea ice response to changed amount and distribution of surface freshwater addition in the Southern Ocean with the ocean–sea ice model NEMO/LIM2. We find that freshwater addition within the range of current estimates increases the ice extent, but higher amounts could have an opposing effect. The freshwater distribution is of great influence on the ice dynamics and the ice thickness is strongly influenced by it.

Below ground pressurization occurs when there is more moisture in the soil pores than normal, and it can potentially result in landscape degradation. We mapped features that are caused by this overpressurization and generated susceptibility maps to find other areas on the landscape that could be susceptible in the future. The susceptibility maps identified areas that may be sensitive to pressurization and help improve our understanding of potentially hazardous permafrost degradation.

We demonstrate a remote-sensing-based scheme estimating the evolution of ground temperature and active layer thickness by means of a ground thermal model. A comparison to in situ observations from the Lena River delta in Siberia indicates that the model is generally capable of reproducing the annual temperature regime and seasonal thawing of the ground. The approach could hence be a first step towards remote detection of ground thermal conditions in permafrost areas.

The results shown in the present paper consist in predicting the overall viscous behavior of snow from the sole knowledge of the microstructure and the ice viscous behavior. This is done thanks to multi-scale modeling techniques and an original approach is used to handle the nonlinearity of the ice behavior. An application of the developed formulation can be found in the simulation of the densification of the snowpack in order to enhance avalanche risk forecasting.

The mass balance change on Qinghai-Tibet Plateau is the result of interactions between the atmospheric vapor and the surface water resources. We evaluated the spatial characteristics and principal components of mass balance change using CPCA and wavelet analysis. The results reflect the change in four major different atmospheric circulation patterns and their contribution percentages to mass balance. The novelty of the phase information revealed their impact area and travel route in detail.

Sub-meter satellite stereo images (Pléiades and WorldView2) are used to accurately measure snow accumulation and winter mass balance of Drangajökull ice cap. This is done by creating and comparing accurate digital elevation models. A glacier-wide geodetic mass balance of 3.33 ± 0.23 m w.e. is derived between October 2014 and May 2015. This method could be easily transposable to remote glaciated areas where seasonal mass balance measurements (especially winter accumulation) are lacking.