In permafrost environments, the ground surface moves due to the formation and melt of ice in the ground. This study compares ground surface displacements measured from satellite images against field data of ground ice contents. We find good agreement between the detected seasonal subsidence and observed ground ice melt. Our results show the potential of satellite remote sensing for mapping ground ice variability, but also indicate that ice in excess of the pore space must be considered.

Rock glaciers are landforms generated by the creep of frozen ground (permafrost) in cold-climate mountains. Mapping rock glaciers contributes to documenting the distribution and the dynamics of mountain permafrost. We compiled inventories documenting the location, the characteristics, and the extent of rock glaciers in 12 mountain regions around the world. In each region, a team of operators performed the work following common rules and agreed on final solutions when discrepancies were identified.

Lakes can form beneath the large ice sheets and can influence ice-sheet dynamics and stability. Some of these subglacial lakes are active, meaning that they periodically drain and refill. Here we report seven new active subglacial lakes close to the Antarctic Ice Sheet margin using satellite measurements of ice surface height changes in a region where little was known previously. These findings improve our understanding of subglacial hydrology and will help refine subglacial hydrological models.

In northern Norway we have observed several rock glaciers at sea level. Rock glaciers are landforms that only form under the influence of permafrost, which is frozen ground. Our investigations show that the rock glaciers are probably not active under the current climate but most likely were active in the recent past. This shows how the Arctic now changes due to climate changes and also how similar areas in currently colder climates will change in the future.