A. Decaulne, CNRS UMR6042 Geolab, Clermont-Ferrand, France, pursues researches coupling geomorphic dynamics occurring on slopes (mostly snow avalanches and debris flows) and dendrogeomorphology in Iceland, in collaboration with Þ. Sæmundsson (Natural Research Centre of Northwestern Iceland, Sauðárkrókur) and Ó. Eggertsson (Iceland Forest Service, Research Branch, Mogilsá). Field work was done on this topic during the summer 2009 in Northern Iceland. For comparison, two other sites were investigated in Nordfjord, Norway, in collaboration with A. A. Beylich and K. Laute (Geological Survey of Norway, Trondheim). Results obtained during the recent studies were presented during the 7th International Conference on Geomorphology IAG/AIG, held in Melbourne in July 2009, and during the Working group SEDIBUD Workshop held in Kingston, Canada, in October 2009.
Research is also carried out on a glacier system of Svalbard since 2006. The objective of Hydro-sensor-FLOWS project (IPY#16) is to investigate the hydrology of the Austrelovenbre Glacier basin (Brogger peninsula) by continuous monitoring the space and time dynamics over a 4-years period (2007-2010). The project is coordinated by M. Griselin (UMR Thema) and C. Marlin (UMR IDES) in association with GEODE (Pau) and FEMTO (Besançon). The main objective is to improve our understanding of the system reactivity to contemporary climatic fluctuations. Different methods are used to study the glacier and its hydrology and its dynamics: image loggers (satellites and automatic cameras on the ground), loggers recording climatic data, air temperature at 20 locations on the basin and hydro-geochemical data.
Stream water is sampled for chemical and isotopic analyses. At the end of the Fall 2009 field trip, the team has obtained the hydro-glacio-climatologic data for a third complete hydrological year (October-October). The rain flood events recorded in Autumn 2008 gave information concerning the rain influence in the hydrological processes, while, until that time, the team had recorded only high runoff linked to high air temperature. Summer 2008 has been in the mean 1969-1998 (i.e. colder than 2007). Summer 2009 is different with large summer periods of high air temperatures and several big events of rain. The ablation-accumulation measurements will give accurately the yearly variation in height of the glacier: that will be our second glaciological mass balance. The team noticed that, during Autumn 2008, following the flood event of mid-September, it had to re-do the mass balance measurements at the very end of September. It was totally different that the one made by the beginning of September. The GPR investigation combined with DEM provided a first mapping of the bedrock elevation. The mapping of the glacier basement by GPR is carried out by scientists of FEMTO and AWI Comparing the DEM of 1964, 1995 and 2007, the team has obtained the 3D difference in glacier volume. Since 1964, the Austrelovenbre glacier lost a third of its volume, and 20% since 1995, showing an acceleration in the melting process.
The CLIMAFLU project (2008-2011), endorsed by the ANR program is an international cooperation between France and Russia, led by F. Costard (IDES, CNRS-Université Paris-sud XI), E. Gautier (Laboratoire de Géographie Physique CNRS UMR 8591) and A. Fedorov (Permafrost Institute, RAS, Yakutsk). Investigations of the effect of climate warming on the fluvial dynamics of the Lena river (Yakutia) is the topic of that project. F. Costard (UMR 8148, IDES, CNRS-Université Paris-sud XI) with E. Gautier and D. Brunstein (Laboratoire de Géographie Physique CNRS UMR 8591) carried out investigations on the Lena flood plain at the latitude of Yakutsk. Two expeditions took place in 2009, one in May to study the breakup phase and the second one in July after the flood season. The objective was to set up several data loggers over several islands in order to measure the thermal regime of the permafrost. This study is expected to allow a quantitative analysis of the evolution of islands in a floodplain under a periglacial environment.
C. Grenier, E. Mouche, D. Régnier from LSCE (Laboratoire des Sciences du Climat et de l'Environnement – UMR1572 ) have been developing activities in numerical modeling for permafrost issues over the last years with the purpose of studying the impact of glaciation cycles on underground flow patterns. The application field typically corresponds to a 500 m depth and 50 x 50 km zone around the French underground research laboratory (operated by ANDRA, the French nuclear waste storage agency) at Bures in the eastern part of the Paris Sedimentary Basin. In the present phase, a 3D coupled Thermo-Hydro (TH) module is being developed by D. Régnier (PhD student) within the Cast3M code (www-cast3m.cea.fr), validated against analytical solutions and benchmarked against literature cases. The model involves a Mixed Hybrid Finite Element numerical scheme and includes heat conduction, heat advection, phase change, coupled water flow. It will soon be applied to study permafrost evolution with coupled TH phenomena for various systems at various scales (underground flows in sedimentary layers under thermal stress, river taliks, thermokarst lakes). Other recent activities deal with 1D column modeling of permafrost evolution for climate reconstruction purposes (e.g. Bures, France; Ohrid Lake, Albania).
François Costard (firstname.lastname@example.org)