Spatial and Temporal Variation of Soil Temperatures in the Kuparuk River Basin, Alaska

A series of environmental studies have been carried out in the northern foothills of the Brooks Range and the Arctic Coastal Plain in the Kuparuk River Basin, Alaska to develop a better understanding of the physical and climatic dynamics of an arctic ecosystem. As part of these studies, soil temperature measurements were made continuously at eight locations along a transect from near the Beaufort Sea coast across the coastal plain to the Brooks Range foothills. Soil temperatures measurements were made in the active layer and permafrost to depths exceeding 10 meters. Data collection began at three of these sites in 1986 with other sites being added until 1994. These data sets are of sufficient length to begin showing long-term trends in arctic soil temperature. All locations show a trend to warming soils over the period, especially in the deeper permafrost soils. Soil temperatures at all sites indicate warming of the permafrost and an increase in the active layer thickness. Summertime soil temperatures within the active layer do not indicate warmer soils. This paper summarizes trends observed in soil temperature spanning the last 17 years in the Alaskan Arctic.