CGRG Bibliography of Canadian Geomorphology
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Author : Bradley, R.S.; and England, J.
Date : 1978
Title : Recent climatic fluctuations of the Canadian High Arctic and their significance for glaciology
Publication : Arctic and Alpine Research
Issue : 10(4):
Page(s) : 715-731.
Abstract
Various measures of the character of ablation season conditions in the Candian High Arctic (north of 74 N) are discussed based on an analysis of daily climatic data from Alert, Eureka, Isachsen, Resolute, and Thule. Melting degree day totals appears to be the most useful index of 'summer warmth'. Various indices indicate a marked decrease in summer temperature after 1963. During the same period, annual pecipitation in the north and northwest has increased. Cumulative mass losses on the Devon Island ice cap from 1947/48 to 1962/63 are estimated to be approx 3500 kg mSUP--2 . However, from 1963/64 to 1973/74 a total of <350 kg mSUP--2 have been lost. Significant ice-cap growth is presently limited by low precipitation even when mean summer temperatures are very low; an occasional warm summer may therefore obliterate cumulative mass gains over many years. The post-1963 change in summer climate appears to be related to the massive increase of volcanic dust in the upper atmosphere, primarily due to the eruption of Mt. Agung (March 1963). It is probable that other periods with high atmospheric dust levels (e.g., 1750 to 1880) had summer temperatures at least as cold as the mid to late 1960s. Conversely, the period of very negative balance on the Devon Island ice cap from 1947 to 1963 was probably typical of the period back to 1920 when the atmosphere was relatively free of volcanic dust.
Bibliography of Canadian Geomorphology