The thermal state of permafrost in the nordic area during the international polar year 2007–2009

Abstract

This paper provides a snapshot of the permafrost thermal state in the Nordic area obtained during the International Polar Year (IPY) [2007][2008][2009]. Several intensive research campaigns were undertaken within a variety of projects in the Nordic countries to obtain this snapshot. We demonstrate for Scandinavia that both lowland permafrost in palsas and peat plateaus, and large areas of permafrost in the mountains are at temperatures close to 08C, which makes them sensitive to climatic changes. In Svalbard and northeast Greenland, and also in the highest parts of the mountains in the rest of the Nordic area, the permafrost is somewhat colder, but still only a few degrees below the freezing point. The observations presented from the network of boreholes, more than half of which were established during the IPY, provide an important baseline to assess how future predicted climatic changes may affect the permafrost thermal state in the Nordic area. Time series of active-layer thickness and permafrost temperature conditions in the Nordic area, which are generally only 10 years in length, show generally increasing active-layer depths and rising permafrost temperatures.

Modeling the temperature evolution of Svalbard permafrost during the 20th and 21st century

“…Hilbich et al, 2008Gruber et al, 2004). In general, the active layer change during recent years, and especially during the last decades is similar to observations in other parts of the world (Romanovsky et al, 2010a;Smith et al, 2010;Zhao et al, 2010;Christiansen et al, 2010).…”

“…1, Table 1). An overview of location, landforms, stratigraphy and detailed instrumentation of these sites is given by Christiansen et al (2010). Site information particularly relevant for this study is given below and in Table 1.…”

“…Lütschg et al, 2008), while Engelhardt et al (2010) showed that differences in the timing of a thick snow cover have a similar influence on ground temperature as different forcing climate scenarios. Recently, Christiansen et al (2010) and Romanovsky et al (2010b) demonstrated the large differences of nearsurface ground temperatures between two adjacent boreholes with different snow cover in Svalbard. Deeper ground temperatures will, however, become more similar because of the lateral heat transfer, causing temperatures at greater depths to be integrated over larger surface areas.…”

“…In this paper, we use ground temperatures collected from five boreholes, most of which were established during the International Polar Year project TSP-NORWAY (Permafrost Observatory Project: a contribution to the Thermal State of Permafrost in Norway and Svalbard; Christiansen et al, 2010) to calibrate an 1-D heat conduction model and establish statistical relationships between local ground surface temperatures (GST) and surface air temperatures (SAT) at a nearby meteorological station. This framework enables the reconstruction of borehole temperatures since 1912 using a historical record of air temperature.…”

Polygon pattern geomorphometry on Svalbard (Norway) and western Utopia Planitia (Mars) using high-resolution stereo remote-sensing data

“…Only small differences due to varying gravel contents were observed between the sites. Higher contents of gravel, in particular at the high-centered polygon sites in the upper Adventdalen, would be in agreement with current inactive thermal contraction cracking, because coarser-grained sediments require lower ground temperatures for cracking (b−6°C; Romanovskii, 1985) than the existing average permafrost temperatures on Svalbard (− 2.3°C to − 5.6°C; Christiansen et al, 2010). Furthermore, we found that the smallest polygons are associated with the homogenous silty loess-like deposits in the lower Adventdalen (AD1).…”