Three-dimensional internal structure and characteristics of periglacial landforms as a key to enhance the understanding of process dynamics and sensitivity to climate change

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Permafrost environments often exhibit a great small-scale heterogeneity concerning permafrost occurrence and subsurface characteristics especially at the fringe of discontinuous and sporadic permafrost distribution. Periglacial landforms reflect climatic, topographic and lithological conditions and are indicative for past or modern climatic conditions and subsurface structures. Questions arise concerning the degree of subsurface heterogeneity and its impact on process dynamics.The lack of three-dimensional information on ground characteristics relating to subsurface composition, structure and ice content is one of the major problems in investigating responses of permafrost-affected landforms and their sensitivity to atmospheric warming. Consequently, the central objective of the project is to achieve a detailed three-dimensional assessment of the internal structure and characteristics of typical alpine and subarctic periglacial landforms indicative for frozen ground conditions (glacier forefields, rock glaciers, scree slopes, patterned ground, lithalsas). Different permafrost-affected landforms will exhibit various response/sensitivity to atmospheric warming due to complex interactions between surface and subsurface conditions. Hence, the research approach is based on the assessment of heterogeneities in surface (terrain parameters, texture, ground surface temperatures, snow cover) and subsurface parameters (structure, frost table configuration, ground ice characteristics, ground temperature and moisture) and to correlate these with subsurface processes and geomorphic process dynamics. Subsurface heterogeneities of the geomorphic landforms will be mapped through the novel application of minimal-invasive 3D resistivity imaging.An approach combining both in-situ point measurements at representative sites and 3D subsurface resistivity imaging is thought to be the key to a better knowledge base about heterogeneous periglacial environments with regard to surface and subsurface heterogeneity. The expected new insights will help to improve conceptual models for the different landforms and hence, the development of scenarios for alpine and subarctic landscape evolution under changing environmental conditions.