We present a detailed evaluation of the latest version of the regional climate model RACMO2.3p2 at 11 km resolution (1958–2016) over the Greenland ice sheet (GrIS). The model successfully reproduces the present-day climate and surface mass balance, i.e. snowfall minus meltwater run-off, of the GrIS compared to in situ observations. Since run-off from marginal narrow glaciers is poorly resolved at 11 km, further statistical downscaling to 1 km resolution is required for mass balance studies.

This study presents a reanalysis of the glacier mass balance record at Hintereisferner, Austria, for the period 2001 to 2011. We provide a year-by-year comparison of glaciological and geodetic mass balances obtained from annual airborne laser scanning data. After applying a series of corrections, a comparison of the methods reveals major differences for certain years. We thoroughly discuss the origin of these discrepancies and implications for future glaciological mass balance measurements.

We combine in situ measurements and an ice flow model to study the thermomechanical features of Laohugou Glacier No. 12, the largest valley glacier on Qilian Shan. We reveal that this glacier, once considered to be extremely continental or cold, is actually polythermal with a lower temperate ice layer over a large region of the ablation area. Strain heating and latent heat due to meltwater refreezing in the firn zone play critical roles in controlling the thermal regime of this glacier.

Estimating winter snowpack throughout British Columbia is challenging due to the complex terrain, thick forests, and high snow accumulations present. This paper describes a way to make better snow estimates by combining publicly available data using machine learning, a branch of artificial intelligence research. These improved estimates will help water resources managers better plan for changes in rivers and lakes fed by spring snowmelt and will aid other research that supports such planning.

In our studies of surface temperature in Greenland, we found that there can be differences between the temperature of the snow surface and the air directly above, depending on wind speed and incoming solar radiation. We also found that temperature measurements of the snow surface from remote sensing instruments may be more accurate than previously thought. Our results are relevant to studies of climate change in the remote sensing community and in studies of the atmospheric boundary layer.

L-band (1.4 GHz) brightness temperatures from ESA's Soil Moisture and Ocean Salinity SMOS mission have been used to derive thin sea ice thickness. However, the brightness temperature measurements can potentially be assimilated directly in forecasting systems reducing the data latency and providing a more consistent first guess. We studied the forward (observation) operator that translates geophysical sea ice parameters from the ECMWF Ocean ReAnalysis Pilot 5 (ORAP5) into brightness temperatures.

Large deviations still exist between sea ice forecasts and observations because of both missing physics in models and uncertainties on model inputs. We investigate how the new sea ice model neXtSIM is sensitive to uncertainties in the winds. We highlight and quantify the role of the internal forces in the ice on this sensitivity and show that neXtSIM is better at predicting sea ice drift than a free-drift (without internal forces) ice model and is a skilful tool for search and rescue operations.

We present measurements of ice density that show the melting bare-ice surface of the Greenland ice sheet study site is porous and saturated with meltwater. The data suggest up to 18 cm of meltwater is temporarily stored within porous, low-density ice. The findings imply meltwater drainage off the ice sheet surface is delayed and that the surface mass balance of the ice sheet during summer cannot be estimated solely from ice surface elevation change measurements.

We model the summer acceleration of ice velocities at a land-terminating margin of the Greenland Ice Sheet. Model results compare favourably against GPS data, reflecting positively on the model components and the datasets used. When we run the model into the future, we find that summer velocities increase with increasing levels of surface melt but that changes in annual velocities may be limited.

This work proposes a new data synergy method for the retrieval of sea ice thickness and snow depth by using colocating L-band passive remote sensing and active laser altimetry. Physical models are adopted for the retrieval, including L-band radiation model and buoyancy relationship. Covariability of snow depth and total freeboard is further utilized to mitigate resolution differences and improve retrievability. The method can be applied to future campaigns including ICESat-2 and WCOM.

We imaged first-year sea ice using micro-computed tomography to visualize, capture, and quantify the 3-D complex structure of salt water channels weaving through sea ice. From these data, we then built a mathematical network to better understand the pathways transporting heat, gases, and salts between the ocean and the atmosphere. Powered with this structural knowledge, we can create new modeled brine channels for a given sea ice depth and temperature that accurately mimic field conditions.

This manuscript presents a large latitude and elevation range analysis for snow trends in the Andes using satellite images (MODIS) snow cover product. The research approach is also significant because it presents a novel strategy for defining trends in snow persistence from remote sensing data, and this allows us to improve understanding of climate change effects on snow in areas with sparse and unevenly ground climate data.

Ice sheet flow is anisotropic, depending on the nature of the stress applied. However, most large-scale ice sheet models rely on the Glen flow relation, which ignores anisotropic effects. We implement a flow relation (ESTAR) for anisotropic ice in a large-scale ice sheet model. In ice shelf simulations, the Glen flow relation overestimates velocities by up to 17 % compared with ESTAR. Our results have implications for ice sheet model simulations of paleo-ice extent and sea level rise prediction.

Through the geochemical analysis of the surface snow of a glacier at the northern tip of the Antarctic Peninsula, we aimed to investigate how atmosphere and ocean conditions of the surrounding region are varying under the present climate scenario. We found that meteorological conditions strongly depend on the extension of sea ice. Our results show a slight cooling of the surface air during the last decade at this site. However, the general warming tendency for the region is still on-going.

Future melting of the Greenland Ice Sheet is predicted using regional climate models (RCMs). Here, we assess the ability of the MAR RCM to reproduce observed extreme temperature events and the melt energy produced during these times at 14 locations. We find that MAR underestimates temperatures by >0.5 °C during extreme events, which leads to an underestimate in melt energy by up to 41 %. This is potentially an artefact of the data used to drive the MAR simulation and needs to be corrected for.

The atmospheric influence on the unusually early and strong decrease in Antarctic sea ice in the austral spring 2016 was investigated using data from the global forecast model of the European Centre for Medium-range Weather Forecasts. Weather situations related to warm, northerly flow conditions in the regions with large negative anomalies in sea ice extent and area were frequent and explain to a large part the observed melting. Additionally, oceanic influences might play a role.

We conducted a series of experiments to determine how snowpack properties change with varying snowmobile traffic. Experiments were initiated at a shallow (30 cm) and deep (120 cm) snow depth at two locations. Except for initiation at 120 cm, snowmobiles significantly changed the density, hardness, ram resistance, and basal layer crystal size. Temperature was not changed. A density change model was developed and tested. The results inform management of lands with snowmobile traffic.