Permafrost and climate in Europe: Monitoring and modelling thermal, geomorphological and geotechnical responses

Abstract

We present a review of the changing state of European permafrost within a spatial zone that includes the continuous high latitude arctic permafrost of Svalbard and the discontinuous high altitude mountain permafrost of Iceland, Fennoscandia and the Alps. The paper focuses on methodological developments and data collection over the last decade or so, including research associated with the continent-scale network of instrumented permafrost boreholes established between 1998 and 2001 under the European Union PACE project. Data indicate recent warming trends, with greatest warming at higher latitudes. Equally important are the impacts of shorter-term extreme climatic events, most immediately reflected in changes in active layer thickness. A large number of complex variables, including altitude, topography, insolation and snow distribution, determine permafrost temperatures. The development of regionally calibrated empiricalstatistical models, and physically based process-oriented models, is described, and it is shown that, though more complex and data dependent, process-oriented approaches are better suited to estimating transient effects of climate change in complex mountain topography. Mapping and characterisation of permafrost depth and distribution requires integrated multiple geophysical approaches and recent advances are discussed. We report on recent research into ground ice formation, including ice segregation within bedrock and vein ice formation within ice wedge systems. The potential impacts of climate change on rock weathering, permafrost creep, landslides, rock falls, debris flows and slow mass movements are also discussed. Recent engineering responses to the potentially damaging effects of climate warming are outlined, and risk assessment strategies to minimise geological hazards are described. We conclude that forecasting changes in hazard occurrence, magnitude and frequency is likely to depend on process-based modelling, demanding improved understanding of geomorphological process-response systems and their impacts on human activity. We present a review of the changing state of European permafrost within a spatial zone that includes the continuous high latitude arctic permafrost of Svalbard and the discontinuous high altitude mountain permafrost of Iceland, Fennoscandia and the Alps. The paper focuses on methodological developments and data collection over the last decade or so, including research associated with the continent-scale network of instrumented permafrost boreholes established between 1998 and 2001 under the European Union PACE project. Data indicate recent warming trends, with greatest warming at higher latitudes. Equally important are the impacts of shorter-term extreme climatic events, most immediately reflected in changes in active layer thickness. A large number of complex variables, including altitude, topography, insolation and snow distribution, determine permafrost temperatures. The development of regionally calibrated empiricalstatistical models, and physically based ...

Recent Change—Terrestrial Cryosphere

“…6.5 Cumulative glaciological and volumetric mass balance series of Storglaciären, northern Sweden. Different lines represent different methods and corrections that have been used to estimate the net mass balance active layer thickness (Harris et al 2009). A rise in ground temperature of 0.1-0.7°C at the depth of zero annual amplitude in European Russia was observed during the monitoring period.…”

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

“…On one hand, this effect buffers ground warming, on the other hand it may cause a non-linear ground temperature response if completely thawed. Resulting increases in ALT may in certain areas of Svalbard be associated with unprecedented thaw settlement as ice-rich soils thaw (Nelson et al, 2001), and in consequence, a marked increase in slope instability (Harris et al, , 2009Davis et al, 2001;Gruber and Haeberli, 2007). An important geomorphological consequence for bedrock in coastal areas is coastal erosion.…”

“…These areas are characterized by the presence of mainly marine, raised beach sediments, fluvial and glaciofluvial sediments, partly overlain by eolian, colluvial or alluvial deposits, having a relatively fine matrix . Those sediments are ice-rich, and associated periglacial landforms such as ice wedges, pingos and solifluction sheets or lobes are wide-spread (Christiansen, 2005;Harris et al, 2009;Ross et al, 2007). However, the permafrost thermal snapshot obtained during 2008-2010 from fine-grained sediment landforms in lower Adventdalen, also showed significantly colder permafrost of −5 • C to −6 • C at the depth of ZAA , most likely due to a combination of cold air drainage through these valleys with generally thin snow cover and high ice content.…”

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

“…More recently, permafrost maps were compiled based on interpolated mean annual air temperatures (MAAT) over a 1 km resolution grid for Norway (Etzelmüller et al, 2003 and for the Scandinavian mainland (Harris et al, 2009). These maps are more detailed spatially, but do not distinguish between permafrost types and do not consider ground-ice conditions.…”