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Galloping glaciers by Bill Baird Glacier surges, also known as exceptional or catastrophic advances, galloping glaciers, or pulsatory glaciers, have been observed in many parts of the world. Although hundreds of glaciers are known to surge, and several have been studied at the height of their activity by glaciologists, there is still insufficient data available to allow a precise definition or description of glacial surges. Most descriptions of surging glaciers mention or imply a sudden advance which does not seem to be related to a variation in climate or any other obvious causes. The Black Rapids glacier in central Alaska ran amuck in the autumn of 1936 and gained the attention of the World's press. The 12.5 mile long valley glacier had been retreating slowly for many years prior to 1936 and its terminus was a few miles from the Rapids Roadhouse on the Richardson Highway. Then in November it began to surge and by December its 300 foot high mile wide front could be seen from the roadhouse. Within two months the glacier was threatening not only the roadhouse but the Richardson Highway itself. The New York Times ran a headline saying "Black Rapids Glacier sets a speed record" in a front page story of 23rd February 1937. By March 7th 1937 the tremendous surge of the Black Rapids Glacier, four miles in three months, had brought the ice to within a mile and a half of the roadhouse and the highway. Then the glacier simply ground to a halt and began slowly to retreat once again, leaving scientists at a loss to explain the forces which had set it in motion. General comment on surging glaciers is available
in Glacier, 1982 by Ronald H. Bailey. This is one of the Time-Life series
of books under a general heading Planet Earth. More detailed information
can be gained from the Canadian Journal of Earth Sciences, Vol. 6, 1969,
Pt. 2, Surging Glacier Conference Issue, pp. i-iii & 807-1009.
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