Volumetric change of Klinaklini and Tiedemann Glaciers, Southern Coast Mountains, British Columbia, Canada

Glaciers of the Southern Coast Mountains are an important source of freshwater in the province, but few studies detail their volumetric change. We utilized digital elevation models (DEMs) from aerial photography (1965, 1985) and from Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) imagery (2000, 2006) to calculate thickness and volumetric changes in the ablation zones of Klinaklini and Tiedemann glaciers. The ablation area of Klinaklini Glacier thinned by an average of - 150 ± 17 m and lost -13.9 ± 1.7 km3 during the period 1965-2006 while Tiedemann Glacier thinned -49 ± 20 m and lost -1.1 ± 0.5 km3 over the same interval. Klinaklini Glacier experienced maximum rates of thinning and volumetric change during the period 2000-2006, while the highest rates of thinning and ice loss for Tiedemann Glacier occurred 1985-2000, which corresponds to one of the warmest periods of the 20th century. Differences in size and debris cover may explain the variable response of the glaciers to climate change. Work is in progress to extend the analysis further back using 1949 aerial photography