Glacier Volumes in Alberta

Peyto GlacierGlacier volume measurements require a labour and capital-intensive approach. Volume-Area (V-A) and other scaling relations have been derived from the available global ice-thickness data. Based on empirical volume data from 63 glaciers around the world (seismic and radar), Chen and Ohmura (1990) derived the following curvilinear relationship between glacier area and volume:

V = cAb

where V (106 m3) is the volume and A (km2) is the surface area of the glacier. In their analysis they found c to be 28.5 and b to be 1.357. As the data used to derive these constants is from many different regions, the values for c and b can be considered a sort of world average and c, in particular, needs to be adjusted regionally. To give an idea of the regional variability in c, Chen and Ohmura found a value of 16.1 in the Alps and 48.0 in Svalbard. However, individual glaciers can deviate dramatically from the above formula / relationship as a result of complex or deeply eroded bed topography, unusual ice flow regimes (extensive glacier sliding), or as a result of being far out of equilibrium.

Glacier thickness data is available from six sites in the Rocky Mountains: the Grinnell (Montana), Dinwoody (Wyoming), Haig, Rae, Peyto, and Athabasca Glaciers. The latter four are in Alberta. Glacier volumes are estimated to be 55km3 (± 15km3) for all of the glaciers in the eastern slopes, with 47km3 (± 15km3) in Alberta and the remainder in the eastward-draining ice masses of the Peace River Basin in B.C.

The table below provides glacier area and volume estimates for Alberta river basins, based on the WC2N glacier inventory for 2005. Best estimates are based on the mean prediction from the four volume estimation methods, and modelled values.

River Basin (km2)
(Range)
Area (km2)
(Range)
Glacier Volume (km3)
(Range)
Glacier Volume (km3)
(Estimate)
Glacier Volume (km3)
(Model)
Bow 60.1 2.1 - 3.6 3.0 (± 0.7) 2.9
Red Deer 16.6 0.6 - 1.0 0.9 (± 0.2) 0.8
North Saskatchewan 286.3 13 - 19 17.5 (± 4.4) 15.6
Athabasca 320.5 12 - 18 16.7 (± 4.2) 19.9
Peace (AB) 107.6 6 - 14 8.8 (± 1.4) -
Peace (AB and BC) 276.7 13 - 23 16.9 (± 4.2) 15.8
Alberta 791.1 35 - 55 47 (± 4.2) -
All eastern slopes 960.3 43 - 67 55 (± 4.2) 55.0