The ninth expedition to the Lena River Delta was carried out from May to September by the Alfred Wegener Institute for Polar and Marine Research (AWI) under the aegis of its Department of Periglacial Research (H.-W. Hubberten and colleagues).
Trace gas emissions were recorded over an entire vegetation period; permafrost samples were taken for molecular analyses on methane producing and oxidizing microorganisms; limnological investigations and temperature measurements in permafrost holes were undertaken. These activities were conducted in the context of the Helmholtz-EOS (Integrated Earth Obser-ving System) research network «Land Surface Processes – Carbon Balance». Spectral ENVISAT measurements of vegetation and soil were carried out simultaneously to extrapolate to larger areas the results of local investigations of vegetation models and satellite data. Scientists from the Arctic and Antarctic Research Institute (AARI) and the State University of St. Petersburg (SPbSU), the Lena Delta Preserve (LDR), the Permafrost Institute in Yakutsk (PIY) and the German Aerospace Center (DLR) in Southern Germany participated in the expedition. Two doctoral candidates from AWI and DLR carried out measurements related to the carbon cycle.
L. Schirrmeister and H. Meyer (AWI Potsdam permafrost group) in cooperation with K. Yoshikawa (University of Alaska, Fairbanks) and Jerry Brown in spring 2006 had a field trip to Alaska to continue the fieldwork initiated there in 2004. The main objective was to complete high resolution ice-wedge studies in the buried ice-wedge tunnel near Barrow and sediment studies of the surrounding deposits. Brines were detected by coring in the base of the tunnel at a depth approaching sea level. In addition two local meat cellars were surveyed in Barrow and sampled for stratigraphic and geochronological studies. The second objective was a palaeoenvironmental study of permafrost sequences in a private goldmine near Fairbanks (Vault Creek Valley). Two yet unidentified volcanic ash layers were detected within loess-like deposits. Loess and peat samples were taken for luminescence and U/Th-dating. Blocks of ice-wedge ice were sampled for isotope and trace gas analysis. The upper three meters of the sequence are assumed to be Holocene in age and were sampled by drilling to complete the entire permafrost sequence down to about 40 m deep.
A new cooperation between AWI Potsdam (H. Lantuit, H. Meyer, L. Schirrmeister) and McGill University in Montreal (N. Couture, W. Pollard) began during the Yukon Coast 2006 Expedition based on Herschel Island, west of the Mackenzie River Delta. Field work in July concentrated on permafrost-dominated exposures, their erosion in retrogressive thaw slumps and the subsequent transport and accumulation of sediments in the near-shore zone. The geomorphological survey by helicopter and the research program used DGPS surveys, field spectrometry and soil geotechnical measurements to characterize the shape and surfaces of retrogressive thaw slumps at various stages. Sea bottom sediments and sea water were collected at different near-shore sites around Herschel Island and along the Yukon Coastal Plain to under-stand the carbon budget in coastal permafrost erosion. Further investigations focused on the various forms of subsurface ice (ice wedges, segregated ice and buried glacier ice) and the surrounding deposits and are expected to provide new results about Late Quaternary history of the Yukon Coastal Plain.
Near surface geophysical measurements were carried out in the periglacial rim of Austre Lovénbreen (West Spitsbergen) as part of a cooperation between AWI Potsdam and the CNRS Remote Sensing of the Polar Environment Group at ThéMA Besançon (Université Franche-Comté), with as a field base the joint German- French AWIPEV base in Ny-Ålesund. Estimates of glacial run-off characteristics are an essential part of this ongoing environmental monitoring programme. Acquired GPR profiles are expected to reveal frozen ground architecture in the glacier forefield (G. Schwamborn).
A new collaboration between the AWI (A. Morgenstern, G. Grosse, L. Schirrmeister), the Institute for Planetary Research of the German Aerospace Center DLR (E. Hauber, D. Reiss), and the Institute for Geosciences of the Free University Berlin (S. V. Gasselt) was initiated in the spring about morphological features in western Utopia Planitia, Mars. The study region displays polygonally dissected terrain, pits and depressions in a mantling deposit quite similar to terrestrial permafrost features. This study focuses on possible permafrost degradation features and comparison with analogous terrestrial landscapes. High Resolution Stereo Camera (HRSC) and THEMIS-VIS images were used for mapping and spatial analysis in a GIS. Moreover, Mars Orbiter Camera Narrow Angle (MOCNA) images, with a higher spatial resolution, were examined for comparisons with HRSC and closer analysis of permafrost features. Topographic information was derived from individual tracks of the Mars Orbiter Laser Altimeter (MOLA). Observations from the various datasets were compared with field data from Arctic Siberia.
G. Grosse began working in August 2006 on the new research project «Climate-induced permafrost degradation in the Arctic» as an IPY Postdoctoral Fellow for three years at the Geophysical Institute of the University of Alaska Fairbanks. This project focuses on the applications of remote sensing techniques and spatial data analysis methods for the characterization, mapping and quantification of permafrost degradation during the Holocene on a circum-Arctic scale.
A new young researchers group from the Helmholtz Association of German Research Centre (HGF) led by J. Boike (AWI) in April started the project «Sensitivity of permafrost in a changing climate: a multiscale perspective » in cooperation with the University of Heidelberg. The first field experiments were carried out in the Bayelva catchment (Spitsbergen, Svalbard) in the spring and on Samoylov Island (Lena River Delta, Siberia) during the summer. Fieldwork included maintaining the automated soil and climate measuring stations, high-resolution aerial photography (using balloons and kites) and setting up new automated stations. On Samoylov, a 27-meter deep permafrost borehole and a polygonal lake were instrumented to continuously monitor data on thermal dynamics.
Monitoring rock glacier kinematics and permafrost distribution (BTS, geophysics) in the Turtmann Valley (Valais, Switzerland) is continued by the University of Bonn (R. Dikau, I. Roer, M. Nyenhuis). The DFG Research Training Group «Landform - a structured and variable boundary layer» (R. Dikau), investigated paraglacial sediment storage and landform evolution in the same area (J.-C. Otto). Quantification of para- and periglacial landforms was performed using geophysical techniques (refraction seismics, electrical resistivity tomography, ground penetrating radar) combined with GIS modelling. The first 2D ERT (electrical resistivity tomography) monitoring in solid permafrost rockwalls was installed in 2005 (M. Krautblatter). The ERT-monitoring was extended to a 3D array in 2006 and is supplemented by seismic surveys. A monitoring of rockwall temperature using a network of self-communicating micro-sensors has been installed in summer 2006 at the same site . I. Roer (University of Bonn / Swiss Federal Institute WSL) continued monitoring rock glacier kinematics in Valais and started a dendrogeomorphological analysis of trees and shrubs growing on creeping mountain permafrost (funded by the German Academic Exchange Service, DAAD).
The Commission on Cold Region Environments (CRE) of the International Geographical Union (IGU) was established in 2004 and has an agreement of co-operation with the IPA. The commission co-organized various sessions at conferences and will be engaged in the International Polar Year 2007/8, mainly in terms of the proposed research programme LUPOG (Land use impact on polar and sub-polar geosystems: extent, significance, perspectives), submitted to the IPY programme office by the steering committee of the CRE commission. LUPOG became part of several core projects.
Permafrost related investigations at Germany’s highest peak, the Zugspitze, continue and focus on geotechnical and hazard aspects. Since former research stressed that the mountain summit is situated close to the limit of permafrost, now – in the context of atmospheric warming – stability is evaluated and the risks connected to rockfalls initiated by permafrost warming or melting are modelled.
C. Hilbich (University of Jena) and C. Hauck (Institute for Meteorology and Climate Research, University of Karlsruhe / Forschungszentrum Karlsruhe) collaborate within the mountain permafrost monitoring project (Geophysical Observation and four-phase Modelling of Ice Content Evolution) with the aim to reliably quantify ground ice contents and its temporal evolution using geophysical monitoring techniques. Permanent electrical resistivity survey lines at several PERMOS (Permafrost Monitoring of Switzerland) sites in the Swiss Alps were installed in 2006 and are monitored on a regular basis.
At the Department of Physical Geography, University of Würzburg, C. Kneisel is continuing his monitoring of permafrost thickness in the Upper Engadin, where shallow boreholes were drilled and instrumented with temperature sensors. His continued collaboration with T. Saemundsson (Natural Research Centre of Northwestern Iceland, Saudårkrokur) on mountain permafrost in central Iceland extended into new ground temperature measurements. Permafrost investigations in a subarctic alpine environment in the Abisko mountains in northern Sweden also continued, with a new altitudinal logger transect spanning from 700 to 1450 m asl. In collaboration with I. Roer (WSL, Zurich), he started new investigations on solifluction and gelifluction process activity. C. Kneisel is collaborating with the EU-funded project SuPerForm (Subarctic Periglacial Landforms), launched in Abisko in September 2006.
A collaboration of several European institutes from the Universities of Bonn (M. Krautblatter, M. Nyenhuis, J.- C. Otto), Jena (C. Hilbich), Karlsruhe (C. Hauck), Würzburg (C. Kneisel), Zurich/WSL (I. Roer), Graz (A. Kellerer-Pirklbauer) and Oslo (H. Farbrot, J. Tolgensbakk, R. Frauenfelder) currently investigates the connection between rock glacier speed up and electrical resistivity decrease using geodetic and geophysical monitoring techniques. The aim is to detect and quantify the processes causing the observed increase in rock glacier velocity in recent years.
Based on meteorological and soil temperature monitoring data compiled by the Department for Geography, Giessen University (L. King), in the Swiss Matter Valley, J. Kuhl investigates the geomorphological changes in the Gornergrat-Stockhorn region. He continues the monitoring of small-scale pattern of permafrost distribution between 3000 and 3400 m asl, with the perspective of a diachronic synoptical mapping of geology, geomorphological changes, permafrost distribution and mass-movement hazards.
As a main outcome of the international symposium organized by L. King and R. Wang (Giessen), in Urumqi, China from August 27 to September 2, participants agreed to apply for an interdisciplinary research project entitled «Water Resources in the Aksu-Tarim River Catchment and the effects of Climate Change» intending to investigate the regional water cycle within the framework of interrelated modules addressing atmospheric, cryospheric and hydrospheric processes and their changes with time. The regional permafrost distribution and especially the role of active layer dynamics will be treated within the cryosphere module.
T. Raab from the group Landscape Ecology and Soil Science (University of Regensburg) started investigations in the valley of the Gállego River, one of the type regions for the reconstruction of Pleistocene glaciations in the Central Spanish Pyrenees. In June and September 2006 field work began on soil sections in the Sabiñánigo-Biescas basin to describe and characterise soil development since the retreat of the Gállego glacier from its LGM-moraines (supposedly 60 ka yrs old). Soil profiles excavated in sediments of different ages provided insight into the pedostratigraphy of landforms. Special attention was paid to the identification of new periods with periglacial dynamics since the LGM.
The Regensburg group carried out research on sites with relict and active periglacial activity in the Front Ranges of Colorado, U.S.A., in the summers of 2005 and 2006. In the framework of a DFG-funded project, M. Leopold, J. Völkel and T. Raab tried to locate permafrost patches at active solifluction lobes and to establish a subsurface model of the weathered zone above the bedrock at the long term ecological research site (LTER) at Niwot Ridge (~3600– 4000 m asl). Combining ground penetrating radar and shallow seismic refraction gave indications about ice lenses. This research continues to give detailed subsurface information of the study area. This project is in cooperation with the University of Colorado at Boulder and the Institute of Arctic and Alpine Research (INSTAAR) represented by N. Caine and P. Birkeland as well as by D. Dethier.
At the Department of Physical Geography (IPG), Freiburg University, S. Vogt continues to host the SCAR King George Island GIS (SCAR KGIS) project of the SCAR Permanent Committee on Antarctic Geographic Information. This project provides a spatial database for King George Island (South Shetland Islands, Antarctica) with a focus on high-resolution data sets for the periglacial areas. Remote sensing is used to map the permafrost areas as a contribution to IPY/ANTPAS activities.
A. Reuther (Department of Earth Sciences, Dalhousie University, Halifax) dated glacial deposits from various mountain systems. Surface exposure ages from the type section of the Würm glaciation at the former Isar-Loisach glacier west of Munich showed that the glaciers reached their maximum extent at the time of the last glacial maximum. However, the measured age distribution showed that the moraines were exposed to moraine degradation due to the melting of dead ice or periglacial slope processes, exhuming erractics from the moraine matrix during the late glacial (18-15.4 ka). This study illustrated that surface exposure dating can also be used as a capable tool for deciphering times of periglacial surface activity and melting of dead ice.
Thomas Herz & Lorenz King (firstname.lastname@example.org)