Multi-Scale Characterization of Polar Permafrost Landscapes by Airborne and Satellite Remote Sensing and In-Situ Geophysical Measurements

• Applicants: Professor Dr. Roland Baumhauer; Dr. Wolfgang Dierking; Professor Dr. Otto Klemm, since 11/2021 (†); Professor Dr. Christof Kneisel; Professor Dr. Tobias Ullmann
• Subject Area: Physical Geography ; Geodesy, Photogrammetry, Remote Sensing, Geoinformatics, Cartography
• Term: from 2017 to 2023
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 329721376

• Final Report Year: 2023

Final Report Abstract

The high northern latitudes of the Arctic have undergone a significant warming over the last decades and climate projections indicate a continuing increase of temperatures. The changing climate conditions imply changes in the eco- and geosystem, e.g. the loss of permanently frozen ground, an increase of the active layer thickness, an increasing frequency of tundra fires, changes of the geomorphological system, changing tundra vegetation composition, changes of the hydrological system, followed by changing greenhouse gas fluxes and gas concentration. To better predict such changes in future it is important to understand regulation relationships and interactions between surface and subsurface properties. The project focussed on the assessment of such relationships on different spatial scales. A combined approach of various remote sensing, geophysical and other in-situ methods was used to derive key surface and subsurface characteristics along a north-south transect located in the Mackenzie Delta Region (Canada). The remote sensing methods focused on the identification and quantification of long-term temporal dynamics based on an analysis of the Landsat archive (1985 to present), as well as on a detailed high-resolution drone and airborne imagery for detailed surface characterization on different spatial scales. The subsurface structures could be derived using multi-dimensional electrical resistivity tomography (ERT), ground-penetrating radar (GPR) and direct active layer thickness measurements. To obtain also temporal variations in thermal and hydrological conditions, temperature and soil matric potential was monitored over a four-year period at several sites using on-site instrumentation (i.e. loggers). The remote sensing-based approach enabled a large-scale characterization of surface properties and vegetation throughout the entire Mackenzie Delta Region and provided distinct information about vegetation changes, greening and shrub expansion. The groundbased approach enabled the derivation of small-scale heterogeneities within the subsurface that appear clearer than previously assumed. The high small-scale heterogeneity makes it difficult to determine concrete relationships. These tend to show up on smaller scales at individual sites, but not uniformly on a large-scale level. On a smaller scale, also high-resolution three-dimensional investigations of individual periglacial landforms were conducted using the same methodological approach. In this context, three-dimensional ERT measurements revealed strong heterogeneities also within two pingos. The results – which are to our knowledge the first high-resolution, threedimensional information about internal pingo structures – reveal distinct deviations to previous theories and rise some questions about pingo formation in general, in this region respectively. An additional investigation of subsurface heterogeneities adjacent to a retreating headwall of a retrogressive thaw slump provided new insights into relationships between permafrost table topography, hydrology, permafrost properties and spatiotemporal development of the slump.

Publications

• Multi-Scale Characterization of Polar Permafrost Landscapes by Airborne and Satellite Remote Sensing and In-Situ Geophysical Measurement. Conference Presentation & Conference Proceedings. EUCOP5, Chamonix Mt. Blanc, France, 23 June - 01 July 2018
  Ullmann, T., Kneisel, C., Baumhauer, R., Sobiech-Wolf, J. & Dierking, W.
  
• Assessing Spatiotemporal Variations of Landsat Land Surface Temperature and Multispectral Indices in the Arctic Mackenzie Delta Region between 1985 and 2018. Remote Sensing, 11(19), 2329.
  Nill, Leon; Ullmann, Tobias; Kneisel, Christof; Sobiech-Wolf, Jennifer & Baumhauer, Roland
  
• Multi-methodological investigation of permafrost related landforms in the NWT, Canada. Poster Presentation. 13th International Young Geomorphologists Meeting, 2019, Wolfshausen, Germany
  Kunz, J., Kneisel, C., Ullmann, T. & Baumhauer, R.
  
• Preliminary Results on TerraSAR-X Time Series Analyses (2018-2019) of Polarimetric and InterferometricFeatures in the Mackenzie Delta Region (Canadian Arctic). Poster Presentation. TerraSAR-X / TanDEM-X Science Team Meeting, DLR Oberpfaffenhofen, Germany, 21-24 October 2019
  Ullmann, T., Sobiech, J. & Baumhauer, R.
  
• Multi-methodological investigation of a retrogressive thaw slump in the Richardson Mountains, Northwest Territories, Canada. Copernicus GmbH.
  Kunz, Julius; Kneisel, Christof; Ullmann, Tobias & Baumhauer, Roland
  
• Multi-methodological three-dimensional investigation of a closed-system Pingo in Northwestern Canada. Pico Presentation. EGU General Assembly, 2021, Vienna, Austria
  Kunz, J. & Kneisel, C.
  
• Three-dimensional investigation of a broad-based closedsystem pingo on the Tuktoyaktuk Peninsula, Northwest Canada. Oral presentation. 2021 Regional Conference on Permafrost & 19th International Conference on Cold Regions Engineering, virtual conference. Winner of PYRN Best Presentation Award
  Kunz, J. & Kneisel, C.
  
• Three‐dimensional investigation of an open‐ and a closed‐system Pingo in northwestern Canada. Permafrost and Periglacial Processes, 32(4), 541-557.
  Kunz, Julius & Kneisel, Christof
  
• Arctic shrub expansion revealed by Landsat-derived multitemporal vegetation cover fractions in the Western Canadian Arctic. Remote Sensing of Environment, 281, 113228.
  Nill, Leon; Grünberg, Inge; Ullmann, Tobias; Gessner, Matthias; Boike, Julia & Hostert, Patrick
  
• Land cover fractions across the greater Mackenzie Delta Region, Canada
  Nill, L., Grünberg, I., Ullmann, T., Gessner, M., Boike, J. & Hostert, P.
  
• Three-dimensional subsurface architecture and its influence on the spatiotemporal development of a retrogressive thaw slump in the Richardson Mountains, Northwest Territories, Canada. Arctic, Antarctic, and Alpine Research, 55(1).
  Kunz, Julius; Ullmann, T.; Kneisel, C. & Baumhauer, R.
  
• Three-dimensional subsurface architecture and its influence on the spatiotemporal development of a retrogressive thaw slump in the Richardson Mountains, NWT, Canada. Poster Presentation. AK Permafrost, 2022, Kaprun, Austria.
  Kunz, Julius; Ullmann, T.; Kneisel, C. & Baumhauer, R.