Glacier changes in the circumpolar Arctic and sub-Arctic, mid-1980s to late-2000s/2011

Abstract

A new inventory record of satellite-derived area, length, elevation range and surface slope changes from the mid-1980s to late 2000s/2011 for 317 land-terminating glaciers and ice caps (GIC) is presented. The investigated GIC are located in 12 geographic regions throughout the circumpolar Arctic and sub-Arctic. This geographic subdivision allows us to examine regional variations in recent glacier changes. The method is based on a semi-automated classification approach which extracts GIC extent from satellite scenes. Most of the observed GIC show a reduction in area, length, elevation range and slope. On regional scale, the observed GIC changed in area between −4 ± 3% (Nuuk, West Greenland; 1987–2003) and −40 ± 4% (Talkeetna, southern Alaska; 1987–2011), equal to shrinking rates between −0.2% yr−1 and −1.7% yr−1. The regional change in length was between −36 ± 13 m (southern British Columbia; 1985–2011) and −481 ± 85 m (southern Ellesmere Island; 1988–2009), equal to −1 ± 0.5 m yr−1 and −23 ± 4 m yr−1. Regional GIC changes can be illustrated by power-law scaling relationships between GIC area and length, elevation range, and surface slope. Here, we find regional variability in scaling parameters in both time and space, which should be considered when estimating global assessments of GIC conditions and changes over time.