About 34% of the world's coasts are affected by Arctic permafrost and are particularly sensitive to climate change. The frozen cliffs lose their cohesion, which is ensured by the permanently frozen matrix as soon as they come into contact with seawater and are immediately transported away by incoming waves.
In the course of the expected warming in the Arctic, which is estimated to be about twice as high as the global average, favourable conditions for coastal erosion will also be created. The effects of this increased coastal erosion are manifold and include changes in the coastal food web. Survey-like studies on coastal erosion in the Arctic exist, but a comprehensive understanding of local processes is lacking, thus preventing any estimation of erosion rates in the future. Therefore, process studies and high-resolution studies on the spatial variability of sediment distribution and organic matter content are necessary to understand the response of Arctic coasts to environmental change. This understanding is indispensable to quantify the amount of eroded sediment and organic material more accurately.
The group "Permafrost Coasts" investigates the velocity and character of sediment and organic matter transport into the Arctic coastal zone.
Using sedimentological and biogeochemical laboratory methods as well as aerial photography, satellite remote sensing and echosounder bathymetry:
- to quantify the content of particulate and dissolved organic material in permafrost sediments and their bottom ice and to characterize its spatial variability;
- to quantify the velocity of Arctic coastal erosion and the significance of extreme events (storms) and thermocarst on sediment input into the sea; and
- the transport paths of the released sediments and the deposition of organic material in coastal areas can be determined.