Rapid climate change is shifting the flux of material from the continents to the arctic shelf seas. Hydrological fluxes have been observed to be increasing, and changes to climate and permafrost are likely to increase mass flux, including organic carbon, from the continents. Most of the important drivers for coastal fluxes point towards increased fluxes in the coastal zone as coastal erosion rates respond to warming, the decrease in sea ice extent and shifts in meteorology. To understand the consequences for the ecological function and the productivity of deltas and the shelf seas, we need an assessment of current flux rates and an understanding of how they depend on environmental forcing factors. Based on a database of coastline position change rates created by the Arctic Coastal Dynamics project, we present estimates of circumpolar arctic coastal flux rates. At a global scale, coastal flux rates are highest for fine-grained, non-consolidated, ice- and carbon-rich coastal segments. Regional scale fluxes are also dependent on nearshore as well as onshore morphology. Coastal erosion of non-consolidated coastlines results in a transfer of most of the permafrost carbon stockpile into the marine realm. An analysis of the available data highlights the need for better spatial and temporal coverage of coastline position change rates. A cluster of IPY projects dedicated to the establishment of coastal observatories further developed the process of networking sites and observatory operators in the arctic coastal zone. Pathways for further development of the network and its data are presented.
Helmholtz Research Programs > PACES I (2009-2013) > TOPIC 1: The Changing Arctic and Antarctic > WP 1.5: The Role of degrading Permafrost and Carbon Turnover in the Coastal, Shelf and Deep-Sea Environment