The annual German-language workshop for permafrost scientists and PYRN members was held on October 15 to 17 at the Potsdam Congress Hotel, the anticipated location of the 11th International Permafrost Conference (ICOP 2016). About 60 scientists and students participated in this small meeting covering a wide range of topics, including alpine permafrost, modern and past periglacial environments, organic matter in permafrost and microbiological processes, remote sensing and landscape dynamics, subsea permafrost and coastal dynamics. This meeting functioned as the kickoff for preparations of the ICOP 2016.
Reports from Potsdam (AWI, GfZ)
In 2012, the first expedition of the newly established Helmholtz Young Investigator Group of Hugues Lantuit (COPER, Coastal Permafrost erosion, organic carbon and nutrient release to the Arctic nearshore zone) took place in July and August on Herschel Island (NW Canada). The Expedition was part of the long-term cooperation between the AWI, McGill University and the Geological Survey of Canada (W. Pollard, G. Manson). A weather station and a monitoring flume, already tested in 2010 and 2011, were deployed at the outlet of a retrogressive thaw slump to monitor water and sediment discharge over several weeks in the field. Several resistivity profiles were run in the same slump as well as other locations along the coast to study the distribution and characteristics of massive ground ice. The new research vessel of the AWI, the FS “Christine” was used as a platform to conduct bathymetrical and mapping surveys of the shore face, as well as sampling of the seafloor. Finally, two lakes and polygons located within the late Pleistocene glacial limit and outside of it were sampled in detail to reconstruct the late Holocene climate variability in the area.
Two outcomes of the EU PAGE21 project have been the creation of a Data Management system (DMS) and the Data Mining Catalogue. The object-oriented PAGE21 DMS for permafrost monitoring data is compatible with international standards and associated with the Global Terrestrial Network for Permafrost (GTN-P). The data mining catalogue is an inventory of available datasets at the 12 PAGE21 sites that will form the bulk of the data to be put into the DMS. PAGE21 has chosen its observing sites to maximize interactions with international initiatives and networks (e.g. GTN-P, INTERACT, ESA DUE Permafrost, FLUXNET). This carefully prepared cooperation with existing networks operating in the Arctic has made it easier to feed input data derived from these networks in the PAGE21 DMS. The first outreach task will consist in continuing engagement of the GTN-P Executive Committee and the National Correspondents to ensure timely reporting of permafrost data into the PAGE21 DMS (workshop in spring 2013).
An expedition on the Alaskan North Slope at the Itkillik River exposure was undertaken by an international team from the USA, Canada, Russia, and Germany (K. Bjella, A. Breen, D. Fortier, C. Johnson, M. Kanevskiy, Y. Shur, and J. Strauss). The overall aim of field work in May 2012 was to study dynamics and consequences of increasing permafrost degradation as well as quality and quantity of organic matter stored in Alaskan Yedoma. Therefore, samples from the bluff and boreholes were taken to study ice wedge degradation, modern cryosoils, geocryolithology, cryostratigraphy, geochronology, biogeochemistry, and paleoecology.
In April 2012, a team from AWI Potsdam and the Permafrost Institute Yakutsk set out by caravan across the Laptev Sea ice from Tiksi to drill boreholes on and offshore the Buor Khaya Peninsula. Permafrost boreholes were drilled down to 50 m bsl, frozen cores were recovered and ground temperatures measured. Coring and geophysical measurements were mutually corroborated and, together with the cores themselves, will improve our understanding of the evolution of permafrost following coastal erosion. During summer, the main focus of an AWI expedition to Muostakh Island located in the Tiksi Bay (Laptev Sea) was the late Quaternary climate and landscape history based on ground ice and sediment analysis. Moreover, studies on the transport of organic matter from permafrost deposits to the Laptev Sea as well as on coastal erosion were conducted.
The German-Russian project “Polygons in tundra wetlands: State and dynamics under climate variability in Polar Regions (POLYGON)” continued fieldwork in July and August in the Indigirka (Kytalyk site) and in the Kolyma lowlands (Pokhodsk settlement). Permafrost researchers, soil and mire scientists, geographers, and biologists from Potsdam, Hamburg, Greifswald, St. Petersburg, Moscow, and Yakutsk participated in this expedition. Meteorological monitoring accompanied intense sampling of the biological inventory of in total 30 polygon ponds. Cryostructures and nutrient contents in permafrost-affected soils of polygon systems were studied in numerous 1-m cores, which were drilled in low-centered polygons and polygon walls. A detailed survey of a model polygon was carried out by estimating surface and vegetation height, active layer depth and plant associations in 1-m-resolution. In addition, thermokarst lakes were limnologically studied by measuring lakes bathymetry, hydrochemistry, and taking short cores from the lake ground.
During 2012 the SPOT Image initiative “Planet Action” supported the Russian-German project "Erosion of the East Siberian Coastline: Measuring the Permafrost Degradation along the Arctic Coast using Satellite Imagery" with new acquisitions of high spatial resolution stereo imagery. In addition, through the Potsdam research cluster PROGRESS, the German Aerospace Center provided large areal coverage RapidEye images for coastal change time series. This enables detailed measuring of recent annual coastal retreat rates and creating estimates of mass fluxes, which had been sparsely available along the ground ice rich Laptev Sea coast. Key coastal monitoring sites are Cape Mamontov Klyk, Buor Khaya Peninsula, and Dmitry Laptev Strait.
A two-week reconnaissance expedition was undertaken by Christine Siegert and Mathias Ulrich (AWI Potsdam) together with the Melnikov Permafrost Institute (Alexander N. Fedorov) to key thermokarst areas around Yakutsk in July 2012. These initial studies are the foundation for the future research project “Short and long-term thermokarst dynamics due to climate changes and human impacts in Central Yakutia, Siberia”, organized by Leipzig University. The SPOT Image initiative “Planet Action” approved new acquisitions of high spatial resolution multispectral SPOT and Pleiades satellite imagery for the project ().
Within the framework of the AWIPEV project KOP132 “Svalbard Permafrost Landforms as Analogues for Mars, SPLAM” a field trip was conducted by the University of Münster (Dennis Reiss, Harald Hiesinger) together with the AWI Potsdam (Mathias Ulrich), the German Aerospace Center (DLR; Ernst Hauber), and the University of Gothenburg (Andreas Johnsson) to investigate periglacial surface structures on the Broegger Peninsula (Svalbard). Studies of analogous terrestrial permafrost landforms were required as reference information for remote sensing data on Mars. These studies included the analysis of solifluction lobes, ice-cored moraines, and sorted patterned ground by Kite Aerial Imagery in high resolution (< 1 cm) of selected sites to continue analysis in 2009 and 2011 for multitemporal studies.
In June and July, the second “Airborne Measurement of Methane” (AIRMETH-2) campaign by Torsten Sachs (GFZ, Potsdam) and Jörg Hartmann (AWI, Bremerhaven) completed the first airborne eddy covariance measurements of methane fluxes from permafrost areas. Barrow, Alaska, served as the staging ground for flux measurements extending across the entire North Slope of Alaska and Inuvik in the Northwest Territories of Canada was the base for measurements covering the Mackenzie Delta and the Yukon Coastal Plain in a collaborative effort with simultaneous ground-based and helicopter surveys by the Geological Survey of Canada. As a part of the collaboration between the recently established Helmholtz Young Investigator Groups TEAM (Trace Gas Exchange in the Earth-Atmosphere System on Multiple Scales) at GFZ and COPER at AWI, the entire coastline, including Herschel Island, was laser-scanned to support coastal erosion studies. About 52 hours of low level flux transects and roughly 85 vertical profiles up to 1600 m were flown during ten days of good flying conditions. Airborne flux measurements were also conducted by TEAM in collaboration with AWI during the Lena-2012 expedition to the Russian-German Research Station Samoylov. Here, a helicopter-towed micrometeorological measurement system (Helipod) was used to determine the turbulent fluxes of latent and sensible heat as well as CO2 along two transects across the entire Lena River Delta.
In August and September the second field campaign on the Tibetan Plateau was conducted by the groups of Dirk Wagner (GFZ, Potsdam), Michael Schloter (HZUG, Munich) and Thomas Scholten (University Tuebingen) within the framework of the PERMATRANS (The permafrost transect) project. Our work focuses on the impact of climate change and human activities on the sensitive permafrost-affected geoecosystems on the Tibetan Plateau. During this campaign permafrost-affected soils along two transects at altitudes between 4,600 and 5,100 m a.s.l. were sampled for soil ecological and molecular biological analyses. The results allow an indicator-based interpretation across scales from molecular biology to plot and landscape scale. Feedback mechanisms and the resultant risk potential related to material fluxes and greenhouse gas emission are of particular interest in the scope of a warming Earth.
News from German universities
At the University of Bayreuth (Department of Ecological Microbiology), Katharina Palmer finished her Ph. D. on anoxic greenhouse gas producing microbial processes in peatlands under the supervision of Marcus A. Horn. Two research articles were published this year. Katharina’s work emphasized Palsa peats, cryoturbated peat soils and emissions of the greenhouse gas nitrous oxide. Cryoturbated peat soils are a hitherto underestimated but significant source of nitrous oxide. Study sites were in northwestern Finnish Lapland and near Seida, Russia. Denitrifying microorganisms release nitrous oxide as an intermediate. Such microorganisms are diverse and display a multitude of physiological capabilities related to nitrous oxide production. A key finding was that the diversity of the denitrifying microbial community was associated with contrasting nitrous oxide emission patterns, highlighting the importance of in-depth information on process-associated microbes.
The team from the University of Cologne (Reka Fülöp, Silke Höfle, Janet Rethemeyer) started working in the Lena Delta in 2010. The initial focus was on determining organic matter turnover and stabilization processes in the active layer of polygon rim and centers using lipid and radiocarbon analyses of bulk soil and soil fractions. This work was expanded by the collection of microbial released CO2 and CH4 by PhD student Silke Höfle and postdoctoral researcher Réka-H Fülöp during the field campaigns in 2011 and 2012. The gas samples, derived from maximum permafrost thaw depth, were pumped into a chamber and transferred to two different types of zeolite kept in a helium atmosphere (see picture). In the Radiocarbon Laboratory of the University of Cologne, the CO2 and CH4 samples will be cryogenically cleaned, separated and analyzed using the ETH Zurich Accelerator Mass Spectrometer. The gas sampling, extraction and measurement are ongoing at the University of Cologne. Our collaborators in these projects are scientist from AWI Bremerhaven (G. Mollenhauer) and Potsdam (J. Boike) and University Hamburg (C. Knoblauch, L. Kutzbach).
At the University of Bonn permafrost research is organized by the Group PermaSlope (working group Permafrost and Slope Failure). The former organizer of the group (M. Krautblatter) has now changed to the Technical University of Munich to run the chair of “monitoring, analysis and early warning of landslides” which results in a number of co-organized projects. The project “Influences of Snow Cover on Thermal and Mechanical Processes in steep Permafrost Rockwalls” went to its second year with Ph.D. student Daniel Draebing supervised by M. Krautblatter and M. Phillips (SLF Davos). In the first field work season, geophysical and geotechnical measurements were done at Steintaelli site and an automatic ERT-monitoring system was installed at Gemsstock site (both Swiss Alps). Laboratory results focusing on p-wave behavior of 22 frozen rocks and resulting ice pressure was published (doi:10.5194/tc-6-1163-2012) and explain the scientific basis for the use of refraction seismics in low-porosity bedrock. Three diploma/master thesis currently investigates the slope movement of a permfrost rockwall using geotechnical methods (C.Halla), the active-layer dynamics using geophysical methods (N. Gorus) and the snow cover distribution by using automatic snow camera photos (C. Bierbaum).Within the Yukon Coast 2012 (BMBF, PI Hughues Lantuit) project M.Krautblatter and M. Angelopolus proceeded to investigate geophysical and geomechanical properties of giant thaw slump son Herschel Island. Our multi-year laboratory efforts on the geomechanics of thawing permafrost rocks have been condensed in a paper on “why permafrost rocks become unstable a rock-ice mechanical model in time and space (DOI: 10.1002/esp.3374).”
Four scientists from the University of Hamburg joined the LENA2012 expedition from 3 July – 5 September 2012 to Samoylov Island in the Lena River Delta. This group consisted of Lars Kutzbach, UHH group leader, studying vertical CO2 and CH4 fluxes from the polygonal landscape; Benjamin R.K. Runkle, post-doc, studying dissolved organic carbon transported through the surface waters of this landscape; Manuel Helbig, M.Sc.-Geography student, researching the hydrology of different micro-topographic units and catchment-scale discharge; and Wiebke Münchberger, M.Sc.-Biology student, studying leaf-gas exchange of the dominant Carex species in this part of the Lena River Delta. This group was also joined in a collaborative relationship by Alexander Sabrekov, Moscow State University, Ph.D. student in the group of Mikhail Glagolev, studying microsite variation in greenhouse gas fluxes. Key activities of this research included installations related to continuous measurements of lateral and vertical fluxes of CO2 and CH4. This instrumentation includes an eddy covariance flux system operated in partnership with Julia Boike (AWI-Potsdam), three discharge weirs to measure lateral water outflow, and continuous dissolved carbon monitoring. Retrieved soil samples have been returned to Germany for analysis of their physical and chemical properties, and will assist in estimating soil organic carbon and nitrogen stocks in the Lena River Delta region. Furthermore, two junior scientists from the University of Hamburg (Ph.D. student Fabian Beermann and M.Sc.-Geosciences-student Nils Hanke) joined the expedition to Pokhodsk within the POLYGON project (see above). The focus of the Hamburg group was on the sampling of 1 m soil cores for investigations of nutrient pools and availabilities in the active layer as well as in the permanently frozen ground.
Field work for 3D electrical monitoring of unstable permafrost rocks in the Matter Valley (CH) as part of the project “Influences of snow cover on thermal and mechanical processes in steep permafrost rock walls (ISPR, TU Munich, University of Bonn, SLF Davos)”.
One of three discharge weirs constructed for outflow measurements in the polygonal tundra of Samoylov Island (photo Benjamin Runkle)