Glacier Monitoring 2003: Local recession less than expected
By Karl Ricker,
Whistler Naturalist Society
Annual surveys of the positions of the termini (snouts) of Overlord and Wedgemount Glaciers were carried out on Aug. 10 and Sept. 21 respectively, melting some surprises. The warm summer of 2003 has had a lot of recent press, with the usual pronouncements that accelerated global warming, brought on by a variety of natural and man-induced forces, were causing havoc with glaciers, especially in the European Alps. So what are the main antagonists, locally, other than a forest fire heated atmosphere?
According to the climatologists and oceanographers, the Pacific Ocean is not one of the causes. The El Nino cycle was finished; equatorial ocean temperatures were near normal, if not beginning to shift to below the long-term average to a La Nina. That is, it was a neutral year or a La Nada. So the elevated atmospheric temperatures were forced by some other climatic factor. How did the glaciers fare in the face of this summers heat wave?
The surveys were interesting not only in view of the unusual summer on the one hand, but also with the observations of remarkable wildlife situations while carrying out the measurements.
The Overlord Glacier survey netted an average 1.4 metre recession only. The two snouts on the above photograph were measured. The snout in the centre, above the arrow, had actually advanced slightly (0.4 metres) compared to last year; whereas the wider snout on the right side of the photo had recessed 3.2 metres the two together thus averaging a (-) 1.4 metre retraction.
The lobe of the glacier on the left-hand side of the photograph, however, underwent significant change. A small lake at its terminus in past years had drained due to the loss of an ice block or seal on the glacier bed.
More surprising however was the presence of 12 mountain goats at the snout of the glacier, rolling in the dust bowls on the recently exposed ground moraine. There were two kids among them and nanny goats were kept busy butting away yearlings that wandered too close to them. Over the summer the goats had stamped out a trail up and over the steep, sharp crested moraine from where the photo was taken. The local goat population appears to be increasing but probably not yet back to the historical herd size of 30 to 40 animals counted around Russet Lake and Fissile Mountain in 1965.
At Wedgemount Glacier the recession for the year was 14.3 metres, significantly more than Overlord, but less than the 18.1 metres of last years survey. The glacier is now about 147-150 metres away from the edge of the lake and 30 metres above it.