Glacier change and contribution to streamflow in the Canoe Basin, British Columbia, 1948-2005

Glaciers provide late-summer runoff to the Columbia River Basin, but few studies quantify glacier runoff and its relation to recent climate variations. This study used digital photogrammetry to map glacier area and volume change in the Canoe Basin, headwaters of the Columbia River, from 1948 to 2005. Historic streamflow and glacier contribution to streamflow were simulated using the HBV-EC hydrologic model.;From 1948 to 2005, glacier area and volume decreased by -3.8 +/- 0.44 km2 (-6.8 +/- 0.79%) and -0.23 +/- 0.14 km 3, respectively. The majority of glacier change occurred from 1985 to 2005. Increasing streamflow from 1947 to 2006 is likely related to increased summer precipitation and not enhanced glacier wastage. Glacier contribution to streamflow decreased from 1947 to 2006, with a higher rate of decrease from 1985 to 2006 than from 1947 to 1985. From 1947 to 2006, glaciers contributed 14-16% (32-38%) of total annual (August) streamflow.