Ground temperature and related permafrost characteristics in west greenland

Abstract

AbstractShallow and surficial ground temperatures in west Greenland are presented and reviewed together with available deep temperature profiles in the unglaciated area of west and southwest Greenland. Ground temperature measurements in Kangerlussuaq (Søndre Strømfjord) reveal a temperature at the depth of zero annual amplitude, TZAA, of −1.6 ± 0.2°C. The average thickness of the active layer is 1.7 m and the permafrost thickness is estimated to be 127 ± 31 m. The permafrost thickness in Sisimiut (Holsteinborg) is estimated to be 33 ± 9m with TZAA at −0.3 ± 0.1°C. In Sisimiut, the average active layer thickness is 2.3 m. Between Kangerlussuaq and the ice sheet margin, permafrost is continuous and the active layer thickness is between 0.15 and 5.0m. The interactions between geomorphology, wind pattern, snowcover characteristics and paths of snow meltwater play an important role in determining the variability in ground temperature and permafrost thickness over short distances. The distribution and redistribution of available water are especially important in the low‐precipitation area near the ice margin in central west Greenland. Therefore soil temperatures tend to be colder in low‐lying, organic‐rich soils with dense vegetation than in sandy, inorganic soils with discontinuous vegetation. Within a west Greenland perspective, ground temperature in Sisimiut is relatively warm and in Kangerlussuaq relatively cold owing to their respectively more oceanic and continental climatic regimes.