Glaciers of the Mcmurdo Dry Valleys, Southern Victoria Land, Antarctica
- John C. Priscu
Published Online: 16 MAR 2013
Copyright 1998 by the American Geophysical Union.
Ecosystem Dynamics in a Polar Desert: the Mcmurdo Dry Valleys, Antarctica
How to Cite
Fountain, A. G., Dana, G. L., Lewis, K. J., Vaughn, B. H. and Mcknight, D. H. (1998) Glaciers of the Mcmurdo Dry Valleys, Southern Victoria Land, Antarctica, in Ecosystem Dynamics in a Polar Desert: the Mcmurdo Dry Valleys, Antarctica (ed J. C. Priscu), American Geophysical Union, Washington, D. C.. doi: 10.1029/AR072p0065
- Published Online: 16 MAR 2013
- Published Print: 28 JAN 1998
Print ISBN: 9780875908991
Online ISBN: 9781118668313
- Desert ecology—Antarctica—McMurdo Dry Valleys
The glaciers of the McMurdo Dry Valleys are fundamental to the hydrology and biology of the valleys because they are the only significant source of water. Understanding the controls on the glacial extent and meltwater runoff is fundamental to a process-oriented approach to studying the dry valleys ecosystem. The elevation of the equilibrium-line of the alpine glaciers changes dramatically in the dry valleys, probably a result of large gradients in precipitation. Temporally, they have been relatively constant since the Pliocene (3.5 million years), the furthest extent is not more than a few hundred meters from their present positions. Ablation (all forms of mass loss) from the glaciers is dominated by sublimation, which accounts for more than 70% of the total mass loss. However the magnitude of sublimation is about the same as that of temperate glaciers. The salient difference from temperate glaciers is the relatively small fraction of ablation due to melt and results from a combination of very cold ice and insufficient sensible heat for much melting. The cliff faces are crucial for initiating and maintaining stream flow because they are the first part of the glacier to start melting and the last to stop. During melt periods the distribution of glacier area with altitude can control the response of stream flow to temperature variations.