Ice-shelf collapse, climate change, and habitat loss in the Canadian high Arctic
Abstract Early explorers in the Canadian high Arctic described a fringe of thick, landfast ice along the 500-km northern coast of Ellesmere Island. This article shows from analyses of historical records, aerial photographs, and satellite imagery (ERS-1, SPOT, RADARSAT-1) that this ancient ice featur...
| Published in: | Polar Record |
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| Main Authors: | , , |
| Format: | Article in Journal/Newspaper |
| Language: | English |
| Published: |
Cambridge University Press (CUP)
2001
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| Subjects: | |
| Online Access: | http://dx.doi.org/10.1017/s0032247400026954 https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0032247400026954 |
| Summary: | Abstract Early explorers in the Canadian high Arctic described a fringe of thick, landfast ice along the 500-km northern coast of Ellesmere Island. This article shows from analyses of historical records, aerial photographs, and satellite imagery (ERS-1, SPOT, RADARSAT-1) that this ancient ice feature (‘Ellesmere Ice Shelf’) underwent a 90% reduction in area during the course of the twentieth century. In addition, hydrographic profiles in Disraeli Fiord (83°N, 74°W) suggest that the ice-shelf remnant that presently dams the fiord (Ward Hunt Ice Shelf) decreased in thickness by 13 m (27%) from 1967 to 1999. Mean annual air temperatures at nearby Alert station showed a significant warming trend during the last two decades of this period, and a significant decline in the number of freezing degree days per annum. The ice-dammed fiord provides a stratified physical and biological environment (epishelf lake) of a type that is otherwise restricted to Antarctica. Extensive meltwater lakes occur on the surface of the ice shelf and support a unique microbial food web. The major contraction of these ice–water habitats foreshadows a much broader loss of marine cryo-ecosystems that will accompany future wanning in the high Arctic. |
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