Long-Term Glacier Variations Measured by Photogrammetry. A Re-Survey of Tunsbergdalsbreen after 24 Years

Abstract The relations between geodetic measurements of the surface level variations Δ h and net budget measurements by stakes arc discussed. In 1961, 24 yr. after Finsterwalder’s survey, Tunsbergdalsbreen, the largest and most regular of the 26 outlet glaciers of Jostedalsbreen, was re-surveyed. Th...

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Bibliographic Details
Published in:Journal of Glaciology
Main Author: Kick, W.
Format: Article in Journal/Newspaper
Language:English
Published: Cambridge University Press (CUP) 1966
Subjects:
Online Access:http://dx.doi.org/10.1017/s002214300001902x
https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S002214300001902X
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Summary:Abstract The relations between geodetic measurements of the surface level variations Δ h and net budget measurements by stakes arc discussed. In 1961, 24 yr. after Finsterwalder’s survey, Tunsbergdalsbreen, the largest and most regular of the 26 outlet glaciers of Jostedalsbreen, was re-surveyed. The variations in the length, area, ice thickness, and volume of its tongue are shown. The lake Brimkjelen was 99 m. deep in 1937; it disappeared in 1949. From 1900–40 the whole Jostedalsbre lost 0.4 m./yr., about the same amount as the glaciers of the eastern Alps. The ice thickness of the Tunsbergdalsbre tongue diminished by −Δ h A = 0.46+0.0022 (1500− A ) m./yr. from 1937–61; for the eastern Alps from 1920–50 −Δ h A ≈ 0.53+0.0021 (2850− A ) m./yr. where A is the altitude. The change of Δ h with altitude is much the same. The amounts of the retreat of the Alpine glaciers, of Tunsbergdalshreen, and at Werenskioldbreen, Vestspitsbergen, were the greater the higher the latitude. The numerical relations between Δ h , net budget, and ice movement are shown. The temporary velocity transverse profile of 1937 served as a prototype for the streaming mode of flow, but in 1961 the glacier partially showed Blockschollen movement, although the velocity had decreased by more than 30 per cent. The article is accompanied by a map showing ice surface contours in 1937 and 1961.