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(Article of periodic en Anglais - 2013)

Document title

Thermal properties of a supraglacial debris layer with respect to lithology and grain size

Authors(s) and Affiliation(s)

JUEN M. (1) ; MAYER C. (1) ; LAMBRECHT A. (1 2) ; WIRBEL A. (2) ; KUEPPERS U. (3) ;
(1) Commission of Geodesy and Glaciology, Bavarian Academy of Sciences, Munich, ALLEMAGNE
(2) Inst. of Meteorology and Geophysics, Univ., Innsbruck, AUTRICHE
(3) Earth and Environmental Sciences, Ludwig-Maximilians-Univ., Munich, ALLEMAGNE

Abstract

The ablation experiments with artificial debris cover were performed on the middle tongue of Vernagtferner, a temperate glacier in the Ötztal Alps, Austria. Ten test plots were established with different debris grain sizes and debris thicknesses consisting of different natural material. For each plot, values of thermal conductivity were determined. The observations revealed a clear dependence of the sub-debris ice melt on the layer thickness, grain size, porosity and moisture content. For the sand fraction the moisture content played a dominant role. These test fields were water saturated most of the time, resulting in an increased thermal conductivity. Highly porous volcanic material protected the ice much more effectively from melting than similar layer thicknesses of the local mica schist. However, the analysis of thermal diffusivities demonstrated that the vertical moisture distribution of the debris cover must be taken into consideration, with the diffusivity values being significantly lower in deeper layers

Source

Article of periodic

published at : Geografiska annaler. Series A. Physical geography / ISSN 0435-3676 / CODEN GAPGAP

Editor : Svenska sällskapet för antropologi och geografi, Stockholm - SUEDE (1965)

Millesime : 2013, vol. 95, no3 [pp. 197-209]

Bibliographic references : 20 ref.

Collation : 10 fig., 3 tabl.

Language

Anglais

INIST-CNRS, Cote INIST : 2704 A

Digital Object Identifier

Go to electronic document thanks to its DOI : doi:10.1111/geoa.12011

Tous droits réservés © Prodig - Bibliographie Géographique Internationale (BGI), 2013
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