Fluvial sediment flux to the Arctic Ocean

The paper presents an overview of recent publications on the fluvial suspended sediment flux to the Arctic Ocean. The total suspended matter exported from the Russian territory is 102 x 10(6) t/year and from the Canadian Arctic is 125 x 106 t/year. The total suspended matter (TSM) flux to the Arctic (227 x 10(6) t/year) is very low, only about 1% of the global flux. Mean concentrations of suspended matter and specific sediment discharge are approximately one order of magnitude lower than the global concentration. An analysis of the trends in the sediment loads based on records of up to 62 years in length shows decreases (Yenisey), increases (Kolyma) and stability (Ob). Among the reasons for the very low concentrations and fluxes of suspended sediment in the Arctic rivers are thin weathering crusts on the Arctic watersheds, low precipitation, extensive permafrost, low temperatures for most of the year, large areas of swamps and lakes and a low level of human activity. A stochastic sediment transport model by Morehead et al. [Morehead, M.D., Syvitski, J.P., Hutton, E.W, Peckham, S.D., 2003. Modeling the temporal variability in the flux of sediment from ungauged river basins. Glob. Planet. Change 39, 95-110] is applied to the Arctic rivers to estimate the sediment load increase should the surface temperature of the drainage basin increase. For every 2 degrees C of warming a 30% increase in the sediment flux could result and for each 20% increase in water discharge, a 10% increase in sediment load could follow. Based on this model, an increase of the sediment flux of six largest arctic rivers (Yenisey, Lena, Ob, Pechora, Kolyma and Severnaya Dvina) is predicted to range from 30% to 122% by 2100. (c) 2006 Elsevier B.V. All rights reserved.