Coastal erosion vs riverine sediment discharge in the Arctic Shelf seas

Abstract

This article presents a comparison of sediment input by rivers and by coastal erosion into both the Laptev Sea and the Canadian Beaufort Sea (CBS). New data on coastal erosion in the Laptev Sea, which are based on field measurements and remote sensing information, and existing data on coastal erosion in the CBS as well as riverine sediment discharge into both the Laptev Sea and the CBS are included. Strong regional differences in the percentages of coastal erosion and riverine sediment supply are observed. The CBS is dominated by the riverine sediment discharge (64.4510 6 t a ±1 ) mainly of the Mackenzie River, which is the largest single source of sediments in the Arctic. Riverine sediment discharge into the Laptev Sea amounts to 24.1010 6 t a ±1 , more than 70% of which are related to the Lena River. In comparison with the CBS, the Laptev Sea coast on average delivers approximately twice as much sediment mass per kilometer, a result of higher erosion rates due to higher cliffs and seasonal ice melting. In the Laptev Sea sediment input by coastal erosion (58.410 6 t a ±1 ) is therefore more important than in the CBS and the ratio between riverine and coastal sediment input amounts to 0.4. Coastal erosion supplying 5.610 6 t a ±1 is less significant for the sediment budget of the CBS where riverine sediment discharge exceeds coastal sediment input by a factor of ca. 10.

Indigenous Knowledge and Sea Ice Science: What Can We Learn from Indigenous Ice Users?

“…Given the magnitude of recent changes observed in Arctic sea ice and coastal environments (Rachold et al 2000;Serreze et al 2007), scientific research on and development of strategies for effective adaptation to a changing physical, socio-economic, and geopolitical environment is of increasing importance (e.g., Berkes 2002;Adger et al 2007). Here, local, indigenous sea ice use and the associated body of expertise have much to offer, in particular at a time where appropriate response strategies are very much under discussion and a theoretical framework is only slowly evolving.…”

Coastal dynamics at the Barents and Kara Sea key sites

“…This process releases solid sediments, dissolved chemical compounds, organic carbon, and pore gases into the sea. Available estimates show that the input of solid sediments from the destruction of shores into the Arctic basin is considerable and comparable to or even exceeds sediment discharge by large rivers Rachold et al 2000Rachold et al , 2003Romankevich and Vetrov 2001;Stein and Macdonald 2003).…”

Diversity of Arctic pelagic <i>Bacteria</i> with an emphasis on photoheterotrophs: a review

“…The total volume and extent of the sea ice are decreasing (Walsh, 2008) leading to an increase of river runoff (Peterson et al, 2002) and a decrease in the surface layer salinity of the Arctic Ocean (ACIA, 2005). An additional consequence is the accelerating permafrost melting (Nelson, 2003) and coastal erosion (Rachold et al, 2000). The increasing delivery of organic carbon is suspected to enhance the mineralization process carried out by heterotrophic bacteria in the estuarine and coastal Arctic Ocean (Meon and Amon, 2004) and thus release a large amount of CO 2 into the atmosphere (Kling et al, 1991).…”