Abstract
We report on a glacier inventory for the Canadian Cordillera south of 60°N, across the two western provinces of British Columbia and Alberta, containing ~ 30,000 km2 of glacierized terrain. Our semi-automated method extracted glacier extents from Landsat Thematic Mapper (TM) scenes for 2005 and 2000 using a band ratio (TM3/TM5). We compared these extents with glacier cover for the mid-1980s from high-altitude, aerial photography for British Columbia and from Landsat TM imagery for Alberta. A 25 m digital elevation model (DEM) helped to identify debris-covered ice and to split the glaciers into their respective drainage basins. The estimated mapping errors are 3-4% and arise primarily from seasonal snow cover. Glaciers in British Columbia and Alberta respectively lost - 10.8 ± 3.8% and - 25.4% ± 4.1% of their area over the period 1985-2005. The region-wide annual shrinkage rate of - 0.55% a- 1 is comparable to rates reported for other mountain ranges in the late twentieth century. Least glacierized mountain ranges with smaller glaciers lost the largest fraction of ice cover: the highest relative ice loss in British Columbia (- 24.0 ± 4.6%) occurred in the northern Interior Ranges, while glaciers in the northern Coast Mountains declined least (- 7.7 ± 3.4%).
Original language | English |
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Pages (from-to) | 127-137 |
Number of pages | 11 |
Journal | Remote Sensing of Environment |
Volume | 114 |
Issue number | 1 |
DOIs | |
Publication status | Published - 15 Jan 2010 |
Keywords
- Band ratio
- Glacier inventory
- Glacier recession
- Image classification
- Landsat TM
- Scaling method
- Western Canada