Stream 2 : Biogeochemical processes and fluxes at the land – sea interface
- I. Bussmann1, G. Tanski2,3, B.P. Koch4, K. Wiltshire5
- 1 Department of Shelf Sea System Ecology, Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research, Bremerhaven, Germany
- 2 Department of Periglacial Research, Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research, Potsdam, Germany
- 3 Department of Ecological Chemistry, Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research, Bremerhaven, Germany
- 4 Institute for Earth and Environmental Science, University of Potsdam, Potsdam, Germany
- 5 Department of Coastal Ecology, Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research, Bremerhaven, Germany
Arctic coasts account for 34% of the Earth’s coasts and are entirely part of the Arctic permafrost. Permafrost coasts are extremely vulnerable to climate change and human impact: Arctic warming is expected to be roughly twice as high as the global mean, resulting in rising sea-level, decline of sea-ice cover, longer open-water periods, and thus conditions amplifying coastal erosion. With erosion rates as high as 25 m·yr-1, the release of organic carbon and nutrients from permafrost coasts has dramatic impacts on the global carbon cycle, on nearshore food webs and on local communities, which still rely on marine biological resources. Nearshore ecosystems, located in traditional hunting and fishing grounds, might be impacted by high loads of sediments and nutrients released from eroding coasts. Ultimately, coastal retreat leads to a loss of natural habitat for flora and fauna and threatens cultural heritage from indigenous people and early explorers along the coasts.
Polar estuaries differ from temperate and tropical estuaries mostly by seasonality: During winter, almost no runoff occurs, followed by an enormous spring freshet. Moreover, the drainage basins of polar rivers and estuaries are dominated by permafrost soils, which influence the flow path of ground water and the input of dissolved nutrients and organic matter. The aim of this session is to highlight the specific changes in polar estuaries and to merge the knowledge between polar and temperate studies.
The session seeks to attract polar scientists and aims at a linkage to studies outside the Arctic to improve the mechanistic understanding of estuaries in general and to answer climate change related questions. We also welcome contributions of a multi-disciplinary nature linking physical and socioeconomic processes in the Arctic coastal zone.