Application of the Gravity Flow Theory to the Percolation of Melt Water Through Firn

Abstract Application of the gravity flow theory to the percolation of melt water through the firn in the accumulation area of a temperate glacier explains the occurrence of shock fronts in the melt-water flux. The time of propagation of a shock front moving from the surface through the entire firn w...

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Bibliographic Details
Published in:Journal of Glaciology
Main Authors: Ambach, W., Blumthaler, M., Kirchlechner, P.
Format: Article in Journal/Newspaper
Language:English
Published: Cambridge University Press (CUP) 1981
Subjects:
Online Access:http://dx.doi.org/10.1017/s0022143000011230
https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0022143000011230
Description
Summary:Abstract Application of the gravity flow theory to the percolation of melt water through the firn in the accumulation area of a temperate glacier explains the occurrence of shock fronts in the melt-water flux. The time of propagation of a shock front moving from the surface through the entire firn was calculated under various assumptions. Various time input functions of melt-water flux at the surface with constant total input volumes yield only slight differences in the time of propagation of the shock front at greater depths. The dependence of the time of propagation of a shock front on the input volume, on snow parameters, and on the total thickness of the firn was calculated. An approximately linear relation was found to exist between the time of propagation of a shock front moving through the firn and the total thickness of the firn. The drainage of melt water from the firn after the summer ablation period is also quantitatively explained by the gravity flow theory. All results are in good agreement with experimental data.