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

A Ekici (1, 2) , S Chadburn (3) , N Chaudhary (4) , L.H. Hajdu (5) , A Marmy (6) , S Peng (7, 8) , J Boike (9) , E Burke (10) , A. D. Friend (5) , C Hauck (6) , G Krinner (7) , M. Langer (7, 9) , P.A Miller (4) , C Beer (1)

1 Stockholm University
2 MPI-BGC - Max Planck Institute for Biogeochemistry
3 University of Exeter
4 Skane University Hospital [Lund]
5 CAM - University of Cambridge [UK]
6 Department of Geosciences [Fribourg]
7 LGGE - Laboratoire de glaciologie et géophysique de l'environnement
8 LSCE - Laboratoire des Sciences du Climat et de l'Environnement [Gif-sur-Yvette]
9 AWI - Alfred-Wegener-Institut, Helmholtz-Zentrum für Polar- und Meeresforschung = Alfred Wegener Institute for Polar and Marine Research = Institut Alfred-Wegener pour la recherche polaire et marine
10 MOHC - Met Office Hadley Centre

Modeling soil thermal dynamics at high latitudes and altitudes requires representations of physical processes such as snow insulation, soil freezing and thawing and sub-surface conditions like soil water/ice content and soil texture. We have compared six different land models: JSBACH, OR-CHIDEE, 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.

Domaines: Sciences de l'environnement

A Ekici, S Chadburn, N Chaudhary, L.H. Hajdu, A Marmy, et al.. Site-level model intercomparison of high latitude and high altitude soil thermal dynamics in tundra and barren landscapes. The Cryosphere, 2015, 9 (4), pp.1343-1361. ⟨10.5194/tc-9-1343-2015⟩. ⟨insu-01285017⟩