Permanent Ice Covers of the Mcmurdo Dry Valleys Lakes, Antarctica: Liquid Water Contents
- 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
Fritsen, C. H., Adams, E. E., Mckay, C. P. and Priscu, J. C. (1998) Permanent Ice Covers of the Mcmurdo Dry Valleys Lakes, Antarctica: Liquid Water Contents, 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/AR072p0269
- Published Online: 16 MAR 2013
- Published Print: 28 JAN 1998
Print ISBN: 9780875908991
Online ISBN: 9781118668313
- Desert ecology—Antarctica—McMurdo Dry Valleys
A novel method of analyzing ice temperature records is applied to several years of data from Lake Hoare and Lake Bonney (Antarctica) to estimate vertical distributions of liquid water in the perennial ice covers at the end of summer melting seasons. Three years of ice temperature data at Lake Bonney (1993–1995) show that the ice contained 20% liquid water located at 1 to 2.5 m below the ice surface near the end of all three melting seasons. Liquid water fractions at Lake Hoare were low (<15%) throughout the ice column in 1986. In 1987 and 1988 liquid water fractions increased to a maxima of 70% at depths between 1.5 and 2.5 m. Maxima in liquid water content for both lakes were coincident with layers of bubbles having arching morphologies which were predominantly associated with pockets of sedimentary material (silts, sand, and gravel). Interpreting these bubble morphologies in context of the ice energy budgets indicates that the majority (>90%) of the liquid water in the ice is generated when visible radiation is absorbed by lithogenic matter within the ice during the austral summer. Our work also demonstrates the potential use of this energy budget analysis for monitoring ecosystem-level responses to climate variability.