Dielectric Relaxation in Temperate Glaciers
The dielectric relaxation of névé and glacial ice has been studied on two temperate glaciers in Greenland and France. Measurement of the capacitance and loss tangent in the audio-frequency range of thin parallel wires placed on the surface of a glacier gave ϵ ′, the relative permittivity, and ϵ ″, t...
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Cambridge University Press (CUP)
1967
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Online Access: | http://dx.doi.org/10.1017/s0022143000020190 https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0022143000020190 |
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crcambridgeupr:10.1017/s0022143000020190 2024-03-03T08:44:36+00:00 Dielectric Relaxation in Temperate Glaciers Gribbon, P. W. F. 1967 http://dx.doi.org/10.1017/s0022143000020190 https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0022143000020190 en eng Cambridge University Press (CUP) Journal of Glaciology volume 6, issue 48, page 897-909 ISSN 0022-1430 1727-5652 Earth-Surface Processes journal-article 1967 crcambridgeupr https://doi.org/10.1017/s0022143000020190 2024-02-08T08:36:10Z The dielectric relaxation of névé and glacial ice has been studied on two temperate glaciers in Greenland and France. Measurement of the capacitance and loss tangent in the audio-frequency range of thin parallel wires placed on the surface of a glacier gave ϵ ′, the relative permittivity, and ϵ ″, the loss factor of the névé . The relaxation time can be expressed in terms of the frequency f m at the maximum ϵ ″ value of the Cole-Cole ϵ ″− ϵ ′ diagram, and its variation with depth was derived from the Cole-Cole diagrams obtained for different wire separations. For wet 0°C. surface snow in Greenland, f m ≈ 4 kHz. and decreased with the increase in density and form factor at greater depths, while for the low-density, cold surface névé in France f m ≈ 2 kHz. and increased with the increase in temperature at greater depths. All Cole-Cole diagrams showed both impurity-ion losses at low frequencies below 6 kHz., and a spreading factor of the distribution in relaxation times caused by the changes in the physical properties of the glacier with depth. Although the method could not measure temperatures absolutely, relative temperature differences and the position of the 0°C. isotherm were detected when a temperature gradient existed in a glacier. Article in Journal/Newspaper glacier Greenland Journal of Glaciology Cambridge University Press Greenland Journal of Glaciology 6 48 897 909 |
institution |
Open Polar |
collection |
Cambridge University Press |
op_collection_id |
crcambridgeupr |
language |
English |
topic |
Earth-Surface Processes |
spellingShingle |
Earth-Surface Processes Gribbon, P. W. F. Dielectric Relaxation in Temperate Glaciers |
topic_facet |
Earth-Surface Processes |
description |
The dielectric relaxation of névé and glacial ice has been studied on two temperate glaciers in Greenland and France. Measurement of the capacitance and loss tangent in the audio-frequency range of thin parallel wires placed on the surface of a glacier gave ϵ ′, the relative permittivity, and ϵ ″, the loss factor of the névé . The relaxation time can be expressed in terms of the frequency f m at the maximum ϵ ″ value of the Cole-Cole ϵ ″− ϵ ′ diagram, and its variation with depth was derived from the Cole-Cole diagrams obtained for different wire separations. For wet 0°C. surface snow in Greenland, f m ≈ 4 kHz. and decreased with the increase in density and form factor at greater depths, while for the low-density, cold surface névé in France f m ≈ 2 kHz. and increased with the increase in temperature at greater depths. All Cole-Cole diagrams showed both impurity-ion losses at low frequencies below 6 kHz., and a spreading factor of the distribution in relaxation times caused by the changes in the physical properties of the glacier with depth. Although the method could not measure temperatures absolutely, relative temperature differences and the position of the 0°C. isotherm were detected when a temperature gradient existed in a glacier. |
format |
Article in Journal/Newspaper |
author |
Gribbon, P. W. F. |
author_facet |
Gribbon, P. W. F. |
author_sort |
Gribbon, P. W. F. |
title |
Dielectric Relaxation in Temperate Glaciers |
title_short |
Dielectric Relaxation in Temperate Glaciers |
title_full |
Dielectric Relaxation in Temperate Glaciers |
title_fullStr |
Dielectric Relaxation in Temperate Glaciers |
title_full_unstemmed |
Dielectric Relaxation in Temperate Glaciers |
title_sort |
dielectric relaxation in temperate glaciers |
publisher |
Cambridge University Press (CUP) |
publishDate |
1967 |
url |
http://dx.doi.org/10.1017/s0022143000020190 https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0022143000020190 |
geographic |
Greenland |
geographic_facet |
Greenland |
genre |
glacier Greenland Journal of Glaciology |
genre_facet |
glacier Greenland Journal of Glaciology |
op_source |
Journal of Glaciology volume 6, issue 48, page 897-909 ISSN 0022-1430 1727-5652 |
op_doi |
https://doi.org/10.1017/s0022143000020190 |
container_title |
Journal of Glaciology |
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6 |
container_issue |
48 |
container_start_page |
897 |
op_container_end_page |
909 |
_version_ |
1792500091495383040 |