Terrestrial ecosystems in polar and high mountains including soils, sediments, glaciers and surface–subsurface waters are critical for sustaining biodiversity and life. Projected climate change during the 21st century will produce alterations to ecosystems in these fragile environments. Predicted climate changes will likely alter melt season timing and duration, decrease the extent of permafrost, increase the size of the active layer and change its spatial distribution and seasonal dynamics. Ice surfaces, soils, sediments, hydrology and vegetation are responding to these climate changes. As a consequence we are witnessing rapidly changing landscapes in which the natural processes of soil formation and sediment redistribution are changing, particularly in polar and high mountain regions. These changes impact and present challenges for local populations which are having to adapt quickly to new threats in terms of their soil and water resources.

This session aims to improve our understanding of the impact of climate change on the processes operating in terrestrial environments following glacier retreat and the exposure of new ice-free surfaces. Polar and high mountain regions are experiencing changes in land surface topography; new soil formation; sediment redistribution; changes in water fluxes, associated geochemistry and nutrients. A variety of techniques including stable isotopes, fallout and environmental radionuclides, satellite images, UAV and classical methods are currently used for characterizing, tracing, dating and mapping these changes. Quantitative data are required in order to be able to advise policy makers on how local populations can adapt to changes in these highly sensitive high-latitude and high-altitude regions across the world.