A circumpolar perspective on fluvial sediment flux to the Arctic ocean

Abstract

[1] Quantification of sediment fluxes from rivers is fundamental to understanding landocean linkages in the Arctic. Numerous publications have focused on this subject over the past century, yet assessments of temporal trends are scarce and consensus on contemporary fluxes is lacking. Published estimates vary widely, but often provide little accessory information needed to interpret the differences. We present a pan-arctic synthesis of sediment flux from 19 arctic rivers, primarily focusing on contributions from the eight largest ones. For this synthesis, historical records and recent unpublished data were compiled from Russian, Canadian, and United States sources. Evaluation of these data revealed no long-term trends in sediment flux, but did show stepwise changes in the historical records of two of the rivers. In some cases, old values that do not reflect contemporary fluxes are still being reported, while in other cases, typographical errors have been propagated into the recent literature. Most of the discrepancy among published estimates, however, can be explained by differences in years of records examined and gauging stations used. Variations in sediment flux from year to year in arctic rivers are large, so estimates based on relatively few years can differ substantially. To determine best contemporary estimates of sediment flux for the eight largest arctic rivers, we used a combination of newly available data, historical records, and literature values. These estimates contribute to our understanding of carbon, nutrient, and contaminant transport to the Arctic Ocean and provide a baseline for detecting future anthropogenic or natural change in the Arctic.

Arctic (palaeo) river discharge and environmental change: evidence from the Holocene Kara Sea sedimentary record

“…is about three times higher than the modern value, has been measured for times preceding the dam constructed near Krasnoyarsk in 1967 (Table 1; Telang et al, 1991;Holmes et al, 2002). The input of particulate organic matter prior to the dam construction was probably also three times higher than today (i.e., about 0.5 Â 10 6 t yr À1 ).…”

Lithogenic and biogenic particle fluxes on the Lomonosov Ridge (central Arctic Ocean) and their relevance for sediment accumulation: Vertical vs. lateral transport

“…A major contributor is the Lena River (discharge ¼ 523 km 3 /yr), transporting large amounts of dissolved and particulate material, i.e., chemical elements, lithogenic and terrestrial/fluvial organic matter, and nutrients. The annual discharge of total suspended sediments by the Lena River is 20.7 Â 10 6 tons (Holmes et al, 2002;Rachold et al, 2004); particulate organic carbon supply is estimated to reach about 1.2 Â 10 6 tons per year. The Lena River is an important freshwater source characterized by a seasonally pulsed inflow in June/July and moderate inflow during May and August/September (Fig.…”

“…1) is characterized by high export rates of sea ice and high input of suspended and dissolved material by Siberian rivers, both having a great influence on the sedimentary and chemical budgets of the entire Arctic Ocean (Eicken et al, 1997(Eicken et al, , 2000Holmes et al, 2002;. A major contributor is the Lena River (discharge ¼ 523 km 3 /yr), transporting large amounts of dissolved and particulate material, i.e., chemical elements, lithogenic and terrestrial/fluvial organic matter, and nutrients.…”

The water temperature characteristics of the Lena River at basin outlet in the summer period

“…Following the inter-annual variability of the river flow, the annual suspended sediment load (SSL) varies from 16.6 to 26.2 mln t, as measured at Kusur GS (Korotaev, 2012;Holmes et al, 2002;Hasholt et al, 2005). The vast majority of SSL passes by the Kusur cross-section in early summer when snowmelt events provide around 85 % of the total water discharge.…”