Radio-echo soundings of sub-polar glaciers with low-frequency radar
Air-borne radio-echo soundings of sub-polar glaciers in Svalbard have previously been carried out by Soviet scientists using high frequency radar units of 620 and 440 MHz. Later a British/Norwegian group made soundings with 60 MHz equipment. The high frequency radar units seemed to underestimate the...
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Norwegian Polar Institute
1991
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ftjpolarres:oai:journals.openacademia.net:article/2353 2023-05-15T16:22:17+02:00 Radio-echo soundings of sub-polar glaciers with low-frequency radar Hagen, Jon Ove Sætrang, Arne 1991-01-03 application/pdf https://polarresearch.net/index.php/polar/article/view/2353 https://doi.org/10.3402/polar.v9i1.6782 eng eng Norwegian Polar Institute https://polarresearch.net/index.php/polar/article/view/2353/5603 https://polarresearch.net/index.php/polar/article/view/2353 doi:10.3402/polar.v9i1.6782 Copyright (c) 2018 Polar Research Polar Research; Vol. 9 No. 1 (1991); 99-107 1751-8369 info:eu-repo/semantics/article info:eu-repo/semantics/publishedVersion 1991 ftjpolarres https://doi.org/10.3402/polar.v9i1.6782 2021-11-11T19:12:32Z Air-borne radio-echo soundings of sub-polar glaciers in Svalbard have previously been carried out by Soviet scientists using high frequency radar units of 620 and 440 MHz. Later a British/Norwegian group made soundings with 60 MHz equipment. The high frequency radar units seemed to underestimate the ice thicknesses. The 60 MHz radar unit seemed to give more accurate results when compared to areas with gravity surveyed bed. However, both the Soviet and the British equipment seldom recorded bed-echoes in accumulation areas where firn soaking during summer and thus zero temperatures are likely to occur. A low-frequency impulse radar unit of 8 MHz, however, recorded bed echoes in these areas too. In the accumulation area of Kongsvegen depths down to 440 m were recorded. The glacier bed is thus close to sea level at approximately 12 km from the calving front. Soundings were carried out on Brøggerbreen. Lovenbreen and Kongsvegen. Subglacial maps were generated from the data. Internal reflections that were probably caused by englacial drainage channels could be observed. Frequent internal reflections close to the bed could be interpreted as an indication of temperate ice. However, we could not find any distinct upper level of these reflections. Article in Journal/Newspaper glacier Polar Research Svalbard Polar Research (E-Journal) Svalbard Kongsvegen ENVELOPE(12.657,12.657,78.854,78.854) Polar Research 9 1 99 107 |
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Open Polar |
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Polar Research (E-Journal) |
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ftjpolarres |
language |
English |
description |
Air-borne radio-echo soundings of sub-polar glaciers in Svalbard have previously been carried out by Soviet scientists using high frequency radar units of 620 and 440 MHz. Later a British/Norwegian group made soundings with 60 MHz equipment. The high frequency radar units seemed to underestimate the ice thicknesses. The 60 MHz radar unit seemed to give more accurate results when compared to areas with gravity surveyed bed. However, both the Soviet and the British equipment seldom recorded bed-echoes in accumulation areas where firn soaking during summer and thus zero temperatures are likely to occur. A low-frequency impulse radar unit of 8 MHz, however, recorded bed echoes in these areas too. In the accumulation area of Kongsvegen depths down to 440 m were recorded. The glacier bed is thus close to sea level at approximately 12 km from the calving front. Soundings were carried out on Brøggerbreen. Lovenbreen and Kongsvegen. Subglacial maps were generated from the data. Internal reflections that were probably caused by englacial drainage channels could be observed. Frequent internal reflections close to the bed could be interpreted as an indication of temperate ice. However, we could not find any distinct upper level of these reflections. |
format |
Article in Journal/Newspaper |
author |
Hagen, Jon Ove Sætrang, Arne |
spellingShingle |
Hagen, Jon Ove Sætrang, Arne Radio-echo soundings of sub-polar glaciers with low-frequency radar |
author_facet |
Hagen, Jon Ove Sætrang, Arne |
author_sort |
Hagen, Jon Ove |
title |
Radio-echo soundings of sub-polar glaciers with low-frequency radar |
title_short |
Radio-echo soundings of sub-polar glaciers with low-frequency radar |
title_full |
Radio-echo soundings of sub-polar glaciers with low-frequency radar |
title_fullStr |
Radio-echo soundings of sub-polar glaciers with low-frequency radar |
title_full_unstemmed |
Radio-echo soundings of sub-polar glaciers with low-frequency radar |
title_sort |
radio-echo soundings of sub-polar glaciers with low-frequency radar |
publisher |
Norwegian Polar Institute |
publishDate |
1991 |
url |
https://polarresearch.net/index.php/polar/article/view/2353 https://doi.org/10.3402/polar.v9i1.6782 |
long_lat |
ENVELOPE(12.657,12.657,78.854,78.854) |
geographic |
Svalbard Kongsvegen |
geographic_facet |
Svalbard Kongsvegen |
genre |
glacier Polar Research Svalbard |
genre_facet |
glacier Polar Research Svalbard |
op_source |
Polar Research; Vol. 9 No. 1 (1991); 99-107 1751-8369 |
op_relation |
https://polarresearch.net/index.php/polar/article/view/2353/5603 https://polarresearch.net/index.php/polar/article/view/2353 doi:10.3402/polar.v9i1.6782 |
op_rights |
Copyright (c) 2018 Polar Research |
op_doi |
https://doi.org/10.3402/polar.v9i1.6782 |
container_title |
Polar Research |
container_volume |
9 |
container_issue |
1 |
container_start_page |
99 |
op_container_end_page |
107 |
_version_ |
1766010241707671552 |