CGRG Bibliography of Canadian Geomorphology
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Author : Fletcher, J.; Lamoureux, S.; and Lafrenière, M.
Date : 2008.
Title : The influence of recent active layer disturbances on fluvial sediment fluxes in paired Canadian High Arctic watersheds.
Publication : International Arctic Change 2008 Conference. December 9-12, 2008. Quebec City, Quebec.
Issue : Conference Programme and Abstracts
Page(s) : 214.
Abstract
By unit volume, the Arctic Ocean is the largest ocean recipient of terrestrial sediment and freshwater. As climate warming progresses, resultant changes in runoff patterns and landscape morphology could lead to increased fluxes of sediment into the coastal environment. Here we report the results of a fluvial sediment delivery study conducted in paired High Arctic catchments, located at Cape Bounty, Melville Island, NU (74.9°N, 109.5°W). This work represents part of a research program that has been underway at the Cape Bounty Arctic Watershed Observatory (CBAWO) since 2003. In 2007, record summer temperatures and summer rainfall resulted in formation of an unusually deep active layer and high soil moisture levels. These conditions triggered a large number of active layer detachments in both catchments at CBAWO, although the disturbances were more extensive in the West catchment. Throughout the 2008 melt season, many of these disturbances continued to expand and contributed considerable sediment to the rivers. The concentration of suspended sediments (SSC) in the two main rivers reached 2,500 mg/l during both nival melt and late season rain events. During low flow periods, SSC were also substantively higher than pervious years and showed clear influence of inputs from the disturbed sites. Comparison with previous years’ SSC provides an indication of the integrated impact of the permafrost disturbance on watershed particulate fluxes and will assist with evaluating modelling efforts that estimate sediment delivery changes under predicted climate changes.
Bibliography of Canadian Geomorphology