Timing and drivers of mid- to late Holocene ice-wedge polygon development in the Western Canadian Arctic
Ice-wedge polygon formation and development from low-centred to high-centred types are thought to be either linear processes acting on long time-scales or rapid shifts between different regimes. We analyzed six sediment cores from three ice-wedge polygons on the Yukon Coastal Plain to examine the timing and drivers of these dynamics. All sites developed from shallow lakes or submerged polygon environments to low-centred polygons before rapid degradation and drying during the last century. We found that ice-wedge polygon initiation was linked to moderate climatic cooling during the mid-Holocene combined with drainage of lakes. The further conversion to high-centred polygons appeared to have been a rapid process linked to modern climatic warming. Continued warming may thus lead to increasing ice-wedge melt on larger scales and subsequent degradation of ice-wedge polygons, especially if paired with increasing geomorphic disturbances caused by thermokarst and thermo-erosion.
AWI Organizations > Geosciences > Junior Research Group: COPER
AWI Organizations > Geosciences > Junior Research Group: PETA-CARB
AWI Organizations > Graduate Research Schools > POLMAR
Helmholtz Research Programs > PACES II (2014-2020) > TOPIC 3: The earth system from a polar perspective > WP 3.1: Circumpolar climate variability and global teleconnections at seasonal to orbital time scales