CGRG Bibliography of Canadian Geomorphology
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Author : Geertsema, M.; and Clague, J.J.
Date : 2003.
Title : Record of jokulhlaups at Tulsequah and Salmon Glaciers, northwestern British Columbia.
Publication : 3rd Canadian Conference on Geotechnique and Natural Hazards. Sheraton Hotel. Edmonton, Alberta, Canada. June 9 and 10, 2003.
Issue :
Page(s) :
Abstract
Jokulhlaups (glacial outburst floods) from lakes dammed by Tulsequah and Salmon glaciers, northwestern British Columbia, have occurred periodically since the early and middle twentieth century, respectively. The floods commenced after decades of substantial downwasting and retreat of the glaciers from their Little Ice Age maximum positions. We use hydrometric data and other records to reconstruct the times and peak discharges of the floods. Tulsequah Lake, which is dammed by Tulsequah Glacier, and Summit Lake, dammed by Salmon Glacier, initially grew in surface area and volume, but, with continued glacier retreat, they have gradually decreased in size. The first jökulhlaups from these lakes were the largest, and discharges decreased as the lakes diminished in size. Tulsequah Glacier impounds two lakes that have developed at different times as the glacier retreated. Tulsequah Lake formed and began to produce outburst floods approximately a half century before Lake No Lake. Today, Tulsequah Lake is much smaller in size, and produces much smaller floods, than Lake No Lake. As glaciers in northwestern B.C. continue to shrink in response to climate warming, additional glacier-dammed lakes may form. Thus, the hazard of catastrophic outburst floods is expected to continue.
Bibliography of Canadian Geomorphology