Prof. Dr. Guido Grosse
Arctic permafrost landscape dynamics and Earth System feedbacks
Arctic permafrost landscapes change rapidly under the influence of natural and anthropogenic disturbances. My research focuses on the dynamics of disturbances, their landscape-scale impacts, and the resulting feedbacks between permafrost, aquatic environments, and soil carbon pools on geological as well as policy-relevant time scales. In the PETA-CARB project, I am coordinating a small team of enthusiastic young researchers and students and I work on a variety of remote sensing-based analyses of rapid permafrost thaw processes. I am also overseeing the establishment of the new Arctic Permafrost Geospatial Center (APGC) that is planned as a focus point for distribution of permafrost-related geospatial data.
Contact: Guido Grosse
Keywords: thermokarst, remote sensing, change detection, data synthesis, soil carbon pools
Dr. Jens Strauss
Quantification of deep permafrost carbon pools and their vulnerability to mobilization
Arctic landscapes underlain by permafrost are threatened by climate warming and may degrade by gradual active layer deepening or rapid thaw. Moreover, permafrost deposits are estimated to store substantial amounts of ancient carbon that is potentially vulnerable to mobilization. My research focusses on quantitative and qualitative assessments of permafrost deposit organic carbon pools in thermokarst and Yedoma environments of the circum-arctic permafrost region. A second focus will be on the characterization of the vulnerabilities particularly of deep (below 1 m depth) carbon pools to rapid thaw.
Contact: Jens Strauss
Keywords: deep organic carbon, Yedoma, thermokarst, carbon quantity and quality
Dr. Anne Morgenstern
Degradation of ice-rich permafrost by thermal erosion
Thermo-erosional valleys are widely distributed in ice-rich permafrost deposits of arctic lowlands, but have not been systematically investigated over larger regions. The process of thermal erosion not only significantly alters affected landscapes, but can also lead to increased input of sediment, carbon and nutrients into streams, lakes and coastal waters. I quantify the impact of thermal erosion on ice-rich permafrost landscapes using a combination of field work, remote sensing and GIS analyses.
Contact: Anne Morgenstern
Keywords: thermal erosion, permafrost degradation, Yedoma, remote sensing
The large amount of spatial data that are needed and generated during research demands well-structured data management. So my task in the ERC PETA-CARB project is the development of a geodata infrastructure containing standardized geodata for efficient internal use and external dissemination through WebGIS applications and the digital library PANGAEA as part of the implementation of the Arctic Permafrost Geospatial Centers (APGC).
Contact: Sebastian Laboor
Keywords: geodata management, geoinformatics, geodata infrastructure, GIS, cartography
Soil Carbon Pools in Thermokarst-affected Permafrost Terrain
Thermokarst regions are large and fast changing permafrost carbon pools in the Arctic; however, there exist large uncertainties in the amount of carbon stored in these regions. In my PhD-project I investigate soil organic carbon in thermokarst-affected permafrost terrain. The objectives of my study are to characterize the soil carbon pools in thermokarst study regions, to update the soil carbon pool estimation for Arctic river deltas and to investigate the sink/source potential of thermokarst regions. For my project I take soil samples in the field, apply laboratory methods, and estimate the carbon stocks for my study regions based on remote sensing data. My study areas are the Lena Delta and Bykovsky Peninsula in Siberia, and the Yukon-, Ikpikpuk- and Fish Creek river delta in Alaska.
Contact: Matthias Fuchs
Keywords: Soil organic carbon, thermokarst, Arctic river delta, remote sensing, GIS
Dr. Ingmar Nitze
Rapid Permafrost Thaw Dynamics – Remote Sensing and Modeling of Landscape Dynamics
In my PhD Project (University Potsdam) I am using Remote Sensing for the analysis of landscape dynamics in Arctic permafrost regions. My work is focussed on the systematic and automated examination of satellite-data time-series to detect and quantify the spatio-temporal dynamics of rapid permafrost thaw processes. Different study sites, such as the Lena Delta in Siberia or the Alaska North Slope, among others, serve as the key study sites for my research.
Contact: Ingmar Nitze
Keywords: Remote Sensing, Time-series analysis, Geo-informatics, land-surface dynamics, permafrost
Dr. Josefine Lenz
Working title of PhD project: Permafrost and landscape dynamics in Central Beringia
Permafrost landscapes are very dynamic and influenced by complex environmental processes. The formation of thermokarst lakes is typically undergoing a cycle of surface subsidence by ground ice melting, lake initiation, expansion, partial or full drainage, and even re-initiation. In my dissertation project (University Potsdam) I am working on permafrost and lake sediment cores of drained and modern thermokarst lakes to reconstruct past landscape dynamics in central Beringia, Alaska. Understanding paleoenvironmental processes is fundamental to assess future development of permafrost affected environments and their biogeochemical cycles.
Contact: Josefine Lenz
Keywords: paleoenvironmental reconstruction, thermokarst dynamics, permafrost degradation, paleolimnology
Dissolved Organic Carbon in Thermokarst Lakes – Spatial and Temporal Variability
In my PhD-project (University Potsdam) I investigate the concentration of dissolved organic carbon (DOC) in thermokarst lakes in two permafrost regions in Alaska and Siberia. The objectives of my study are to improve the understanding of the carbon cycle in thawing permafrost regions and to estimate the climatic relevance of DOC in the carbon cycle. For my project I take water samples from thermokarst lakes, their inflows and outflows, samples from the hinterland of thermokarst lakes and apply laboratory methods to compare factors that influence DOCconcentrations, the origin of DOC and the temporal variability in two permafrost regions along the Arctic Ocean. My study areas are the Lena Delta and Bykovsky Peninsula in Siberia, and a transect from Teshekpuk Lake to Toolik in Alaska.
keywords: thermokarst lakes, dissolved organic carbon (DOC), permafrost degradation, Yedoma
Ice-rich permafrost thaw under submarine conditions
Geophysical datasets, thermal modelling, and drilling data suggest that most Arctic shelves are underlain by submarine permafrost due to their exposure during the glacial low water stands. The degradation of submarine permafrost could release large quantities of methane into the atmosphere, impact offshore drilling activities, and affect coastal erosion. The degradation of subsea permafrost itself depends on the duration of inundation, warming rate, the coupling of the seabed to the atmosphere from bottom-fast ice, and brine injections into the seabed. The impact of brine injections on permafrost degradation is dependent on seawater salinity, which changes seasonally in response to salt rejection from sea ice formation and terrestrial freshwater inflows. The rate of submarine permafrost evolution and the relative importance of the many controls responsible for thawing, however, remain poorly understood. My research aims are to:
- Determine submarine permafrost thawing rates on the Bykovsky Peninsula (north Siberia) and Alaska North Slope using a combination of geophysical, sampling, and remote sensing methods
- Determine the relative impact of submarine permafrost thaw mechanisms by linking coupled heat and salt transport numerical models to field data
Contact: Mike Angelopoulos
Keywords: Permafrost, submarine permafrost, planetary analogues, permafrost geophysics, electrical resistivity, GPR, thermal modelling, GIS
Multispectral time-series analyses with Landsat and Sentinel-2 to assess near-surface carbon pool dynamics in North Siberia
The aim of my PhD project (University of Potsdam) is to assess permafrost landscape dynamics in the Arctic based on optical remote sensing imagery. I will combine Landsat and Sentinel-2 images for time-series analyses to be able to identify and map both gradual and abrupt thawing processes in North Siberia. The identified changes in permafrost landscapes help to describe the near-surface carbon pool dynamics. A focus of the project is to develop big data processing strategies to assess large landscapes with long time-series efficiently. This will be approached by using Google Earth Engine, a cloud based platform for Earth science data and analysis enabling planetary-scale processing.
Contact: Alexandra Runge
Keywords: remote sensing, landscape dynamics, carbon pools, Google Earth Engine
Properties of organic matter in Yedoma and Thermokarst deposits
Global warming will continue to warm the Arctic resulting in the degradation of permafrost soils. This leads to large-scale ground subsidence. Vast regions of the Arctic are covered with ice-rich silts containing large ice wedges, known as yedoma The formation of thermokarst lakes is one of the most important forms of permafrost degradation. Consequently, large amounts of previously sequestered carbon can be mobilized and released, which is of global significance for the carbon cycle.
The aim of this research was to reconstruct the late Quaternary depositional environment and organic carbon characteristics of a thermokarst affected landscape. Fieldwork was conducted on Baldwin Peninsula during the West Alaska Summer Expedition 2016. Yedoma and thermokarst exposures and a short thermokarst lake core were sampled. Sedimentological and biochemical parameters, as well as lipid biomarkers were analyzed. A land cover classification map was made from the peninsula using Landsat imagery and a digital terrain model. An estimation of the OC quantity on the peninsula and the loss since the late Pleistocene was made.
The results show that the yedoma and thermokarst deposits accumulated in a stable depositional environment. The yedoma was deposited under drier conditions. The carbon is mainly derived from terrestrial land plants and is poorly degraded due to fast incorporation of the carbon after deposition. About 53 Mt of organic carbon is stored in the frozen deposits on Baldwin Peninsula and it is estimated that about 2 Mt has been lost since the late Pleistocene. The thermokarst deposits pose the largest carbon source of future carbon release.
Climate change resulting in permafrost thaw will affect the yedoma and thermokarst affected areas first, as it is located at the transition of continuous to discontinuous permafrost. Because of the high ice content of the deposits on the Baldwin Peninsula, the deposits are highly susceptible and vulnerable to permafrost thaw. The low degree of degradation of the stored carbon makes these carbon pools an important source for microbial alteration. This poses an important input of carbon to the carbon cycle.
Contact: Loeka Jongejans
Keywords: Yedoma, Baldwin Peninsula, late Quaternary, depositional environment, organic carbon
Guests, Students and Interns
Torben Windirsch (Uni Potsdam)
Filip Matuszewksi (FU Berlin)
Charlotte Haugk (Uni Potsdam)
Judith Johannsen (Uni Freiburg)
Sophie Ertel (Uni Heidelberg)
Former Guests, Students and Interns
Theresa Henning (TU Dresden)
Carolin Geisler (HU Berlin)
Louise Farquharson (University of Alaska Fairbanks)
Kseniia Simonenkova (St. Petersburg State University, Russia + Uni Hamburg)
Alina Karpova (St. Petersburg State University, Russia + Uni Hamburg)
Prof. Dr. Lin Liu (Chinese University of Hong Kong)
Jie Chen (Chinese University of Hong Kong)
Prof Dr. Katey Walter Anthony (University of Alaska Fairbanks, USA)
Alexandr Kizyakov (Moscow State University, Moscow)
Alexandra Veremeeva (Soil Biology and Cryology Lab, Pushchino)
Sonja Liepe (Augsburg University)
Nina Nesterova (Lund University, Sweden)
Eva Gleisberg (Augsburg University)
Paul Göckeritz (University of Potsdam)
Till Hainbach (University of Potsdam)
Kerstin Schlobies (Catholic University of Eichstätt-Ingolstadt)
Julia Thom (University of Potsdam)
Samuel Stettner (University of Potsdam)
Frank Rosendahl (University of Potsdam)
Ann-Kathrin Lohse (University Hamburg)
completed Works (BSc, MSc, Diploma)
Thermokarst Lakes and Drained Lake Basins along a Permafrost Gradient on the Seward Peninsula, Northwestern Alaska
My Master thesis concentrates on the dynamics of thermokarst lakes and drained lake basins along a permafrost gradient on the Seward Peninsula, Northwestern Alaska. I combine remote sensing data with field-based lithological and biogeochemical information from drained lake basin cores to gain a better understanding of the interaction of permafrost and climate with thermokarst lakes and drained lake basins.
Keywords: Permafrost, Thermokarst Lakes, Drained Thermokarst Lake Basins, Drainage, Carbon
Contact: Andreas Fricke
Organic carbon in icy permafrost sediments of the Lena Delta
In the context of my master thesis (a cooperation of Freie Universität Berlin and AWI) I characterize sampled deposits from the Lena Delta (Siberia) concerning its organic‐carbon characteristics. In detail, my work aims to compare organic carbon sequestered in late Pleistocene Yedoma deposits to Holocene thermokarst deposits. The sedimentological and biogeochemical approaches (ice content, TC, TN, TOC, DOC, δ13C, 14C) are conducted at AWI (Potsdam), while organic geochemistry analysis (acetate, biomarkers) are conducted at GFZ (Potsdam).
Contact: Darshan Neubauer
Keywords: Lena Delta, yedoma, thermokarst, organic carbon, biomarker
Cryolithology and biogeochemics of permafrost cores in northern Alaska
My master thesis (a cooperation of AWI Potsdam and University of Potsdam) deals with cryolithological and biogeochemical characteristics of the upper permafrost in the Teshekpuk Lake Special Area, northern Alaska. The primary aim of my thesis is to determine depositional history, carbon and ground ice pools, landscape dynamics and age. My work is based on three permafrost cores taken from upland remnants and one permafrost core from a drained thermokarst lake basin.
keywords: thermokarst, drained lake basin, permafrost, organic carbon
Dr. Thomas Schneider v. Deimling
Kontakt: Dr. Thomas Schneider v. Deimling
Modellberechnungen der Klimafolgen auftauender Permafrostböden (Kopie 1)
Riesige Mengen an gefrorenem Kohlenstoff lagern in Permafrostböden. In meinem Projekt untersuche ich, welche Bedeutung diese Vorkommen für die zukünftige Klimaentwicklung haben. Durch ein fortschreitendes Auftauen dieser Böden wird ein Teil dieses Kohlenstoffs mikrobiell zersetzt und entweicht als Treibhausgas in die Atmosphäre. Mit Simulationsmodellen berechne ich, welche Mengen an Kohlendioxid und Methan durch Permafrostauftauen freigesetzt werden können und welche zusätzliche Klimaerwärmung dadurch zu erwarten ist.
Kontakt: Thomas Schneider von Deimling
Schlüsselwörter: Boden-Kohlenstoff, Treibhausgasemission, Permafrosttauen (Degradation), Modellsimulation, Klimaeffekt
Dr. Frank Günther
Contact: Dr. Frank Günther
Remote sensing of thaw-related landscape dynamics in arctic permafrost regions
To combine my prior scientific interest in permafrost with stereo photogrammetry, remote sensing, surveying and GIS methods as powerful tools studying remote Arctic Regions, I primarily work with historical and modern very high resolution datasets for change detection purposes. My research is focused on investigating the relationship between the long-term and the current thermokarst and thermo-erosion activity, always based on evidence from field observations to support the quantification of permafrost-carbon dynamics.
Contact: Frank Günther
Keywords: thermokarst dynamics, thaw subsidence, arctic coastal erosion, photogrammetry, remote sensing