Polar terrestrial landscapes are now in rapid transition as a result of climatic changes at high latitudes in the last century. Changing vegetation cover, permafrost temperature and active layer thickness are leading to the activation of various permafrost thaw processes. These cryogenic processes may serve as triggering mechanism for enhanced mobilization and lateral transport of sediments and organic matter from permafrost landscapes into freshwater lakes, rivers and ocean. Freshwater lakes as “closed systems” are abundant in the Arctic serving as indicators for environmental changes.

The aim of this scientific Geo.X funded exchange is to jointly study optical properties of dissolved organic matter in lakes across permafrost landscapes and develop remote sensing applications. Geo.X partners are Alfred Wegener Institute (AWI), the Free University of Berlin (FUB), the German Research Centre for Geosciences (GFZ), the German Aerospace Center (DLR).

Dr. Yury Dvornikov is permafrost researcher at the Earth Cryosphere Institute ECI (part of the Tyumen Scientific Centre, Russian Academy of Science, RAS), Tyumen, Russia. He focuses on cryogenic processes and lakes as indicators of environmental changes at high latitudes. The study regions include a range of permafrost landscapes in Western Siberia (Yamal, Tazovskiy) and Eastern Siberia (Lena Delta). Yury is currently working on the applicability of Sentinel-2 optical satellite data (European Space Agency, ESA) for assessment of coloured dissolved organic matter (CDOM) in a variety of Arctic freshwater lakes. In his talk Yury will present first results for lakes under study characterized by different CDOM regimes, results of processing with different atmospheric correction algorithms (Sen2Cor and ACOLITE) and will discuss potential environmental drivers that might explain differences in CDOM among lakes.