Coastal Permafrost

About 34% of the world's coasts are affected by Arctic permafrost and are particularly sensitive to climate change. The frozen bluffs lose the cohesion provided by the permafrost matrix upon contact with seawater and are instantly washed away by incoming waves.

In the course of the expected warming in the Arctic, which is estimated to be about two to four times as high as the global average, favourable conditions for coastal erosion will also be created. The subsequent impacts include threats to infrastructure and changes to the nearshore food-web through the release of sediment and organic matter to the ocean. 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. Further research foci are pollutant amounts in coastal sediments and their release pathways as well as ecosystem services of permafrost coasts.

Using a multitude of methods we investigate:

• the content of particulate and dissolved organic material in permafrost sediments and their bottom ice and its spatial variability,
• the velocity of Arctic coastal erosion and the significance of extreme events (storms) and thermokarst on sediment input into the sea,
• the amount of pollutants in coastal sediments, their release pathways and fate,
• the transport paths of the released sediments and the deposition of organic material in coastal areas,
• and the ecosystem services provided by permafrost coasts as well as how they are changing with the changing climate.