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The little Ice Age glaciation level on Baffin Island, Arctic Canada

1978; Elsevier BV; Volume: 25; Issue: 3 Linguagem: Inglês

10.1016/0031-0182(78)90036-6

1872-616X

Lawrence E. Williams,

Cryospheric studies and observations

Mapping of the perennial snow/ice cover which existed on Baffin Island about 300 years ago, by means of light-toned areas of sparse lichen cover visible on satellite photographs, has made it possible to map the Little Ice Age glaciation level (a type of snowline). Comparison with the modern glaciation level (which is 200–300 m higher) is not meaningful, for it is not necessarily in equilibrium with the present climate. However, energy/mass balance modelling gives a 1963–1972 mean “snowline” which roughly approximates the modern glaciation level, and a 1.5°C temperature decrease gives a similarly rough approximation to the Little Ice Age glaciation level. A more important observation, perhaps, is that the Little Ice Age glaciation level dipped westward, and in west Baffin Island and the Melville Peninsula it was only 100–200 m higher than extensive plateaus of the central Canadian arctic west of Baffin Island. This suggests that these plateaus would have been glacierized early in a glacial episode, and early glacierization of the central Canadian arctic (by its effect on atmospheric circulation) has been considered to be important for inception of the North American ice sheet.