Articles | Volume 9, issue 4
The Cryosphere, 9, 1343–1361, 2015
The Cryosphere, 9, 1343–1361, 2015

Research article 22 Jul 2015

Research article | 22 Jul 2015

Site-level model intercomparison of high latitude and high altitude soil thermal dynamics in tundra and barren landscapes

A. Ekici1,10, S. Chadburn2, N. Chaudhary3, L. H. Hajdu4, A. Marmy5, S. Peng6,7, J. Boike8, E. Burke9, A. D. Friend4, C. Hauck5, G. Krinner6, M. Langer6,8, P. A. Miller3, and C. Beer10 A. Ekici et al.
  • 1Department of Biogeochemical Integration, Max Planck Institute for Biogeochemistry, Jena, Germany
  • 2Earth System Sciences, Laver Building, University of Exeter, Exeter, UK
  • 3Department of Physical Geography and Ecosystem Science, Lund University, Lund, Sweden
  • 4Department of Geography, University of Cambridge, Cambridge, England
  • 5Department of Geosciences, University of Fribourg, Fribourg, Switzerland
  • 6CNRS and Université Grenoble Alpes, LGGE, 38041, Grenoble, France
  • 7Laboratoire des Sciences du Climat et de l'Environnement, Gif-sur-Yvette, France
  • 8Alfred-Wegener-Institut, Helmholtz-Zentrum für Polar- und Meeresforschung, Potsdam, Germany
  • 9Met Office Hadley Centre, Exeter, UK
  • 10Department of Applied Environmental Science (ITM) and Bolin Centre for Climate Research, Stockholm University, Stockholm, Sweden

Abstract. Modeling soil thermal dynamics at high latitudes and altitudes requires representations of physical processes such as snow insulation, soil freezing and thawing and subsurface conditions like soil water/ice content and soil texture. We have compared six different land models: JSBACH, ORCHIDEE, JULES, COUP, HYBRID8 and LPJ-GUESS, at four different sites with distinct cold region landscape types, to identify the importance of physical processes in capturing observed temperature dynamics in soils. The sites include alpine, high Arctic, wet polygonal tundra and non-permafrost Arctic, thus showing how a range of models can represent distinct soil temperature regimes. For all sites, snow insulation is of major importance for estimating topsoil conditions. However, soil physics is essential for the subsoil temperature dynamics and thus the active layer thicknesses. This analysis shows that land models need more realistic surface processes, such as detailed snow dynamics and moss cover with changing thickness and wetness, along with better representations of subsoil thermal dynamics.

Short summary
This paper compares the performance of different land models in estimating soil thermal regimes at distinct cold region landscape types. Comparing models with different processes reveal the importance of surface insulation (snow/moss layer) and soil internal processes (heat/water transfer). The importance of model processes also depend on site conditions such as high/low snow cover, dry/wet soil types.