Global change, Antarctic meteorite traps and the East Antarctic ice sheet
Abstract Numerical models to assess the principal response of large ice caps to climatic changes are used as a guide to the interpretation of field evidence of changes in the glaciological regime in the coastal areas of Victoria Land and north Victoria Land, Antarctica. Based on the theoretical work...
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Online Access: | http://dx.doi.org/10.1017/s0022143000016051 https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0022143000016051 |
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crcambridgeupr:10.1017/s0022143000016051 2024-03-03T08:38:27+00:00 Global change, Antarctic meteorite traps and the East Antarctic ice sheet Delisle, G. 1993 http://dx.doi.org/10.1017/s0022143000016051 https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0022143000016051 en eng Cambridge University Press (CUP) Journal of Glaciology volume 39, issue 132, page 397-408 ISSN 0022-1430 1727-5652 Earth-Surface Processes journal-article 1993 crcambridgeupr https://doi.org/10.1017/s0022143000016051 2024-02-08T08:36:10Z Abstract Numerical models to assess the principal response of large ice caps to climatic changes are used as a guide to the interpretation of field evidence of changes in the glaciological regime in the coastal areas of Victoria Land and north Victoria Land, Antarctica. Based on the theoretical work, the following scenario is proposed: areas within about 300 km from the coast of Victoria Land experienced (i) significantly shallower ice slopes and a lesser degree of glaciation during most of the late Tertiary, (ii) steep slopes and thicker ice than today during glacial stages, and (iii) moderate thinning of the ice in intervening interglacial stages. The model predicts, for central regions of Antarctica, a slightly thinner ice cap (lower snow-accumulation rate) during glacial stages, but an estimated 200 m thicker ice cap in warmer Tertiary climates than today. The calculated “Tertiary ice caps” indicate a probable tendency of periodic surges due to basal melting at the outer fringes. Only modest changes of the ice thickness in reasonably good agreement with the model predictions for the current interglacial stage have been observed on four blue-ice fields, all located within 250 km of the coastline. Investigated ice fields include two meteorite traps — the Allan Hills Icefield and the Frontier Mountain meteorite fields. Antarctic meteorite traps are sustained by very specific glaciological conditions — in particular, only moderate changes in ice thickness over time. The sub-ice topography of these fields was determined by radar measurements and reveals a former, very different glaciological regime, which is interpreted as being associated with glacial processes, operative during the late Tertiary. Field evidence for a hypsithermal event during the Holocene is presented. Article in Journal/Newspaper Antarc* Antarctic Antarctica Ice cap Ice Sheet Journal of Glaciology Victoria Land Cambridge University Press Antarctic Victoria Land East Antarctic Ice Sheet Allan Hills ENVELOPE(159.667,159.667,-76.717,-76.717) Frontier Mountain ENVELOPE(160.333,160.333,-72.983,-72.983) Journal of Glaciology 39 132 397 408 |
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Cambridge University Press |
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crcambridgeupr |
language |
English |
topic |
Earth-Surface Processes |
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Earth-Surface Processes Delisle, G. Global change, Antarctic meteorite traps and the East Antarctic ice sheet |
topic_facet |
Earth-Surface Processes |
description |
Abstract Numerical models to assess the principal response of large ice caps to climatic changes are used as a guide to the interpretation of field evidence of changes in the glaciological regime in the coastal areas of Victoria Land and north Victoria Land, Antarctica. Based on the theoretical work, the following scenario is proposed: areas within about 300 km from the coast of Victoria Land experienced (i) significantly shallower ice slopes and a lesser degree of glaciation during most of the late Tertiary, (ii) steep slopes and thicker ice than today during glacial stages, and (iii) moderate thinning of the ice in intervening interglacial stages. The model predicts, for central regions of Antarctica, a slightly thinner ice cap (lower snow-accumulation rate) during glacial stages, but an estimated 200 m thicker ice cap in warmer Tertiary climates than today. The calculated “Tertiary ice caps” indicate a probable tendency of periodic surges due to basal melting at the outer fringes. Only modest changes of the ice thickness in reasonably good agreement with the model predictions for the current interglacial stage have been observed on four blue-ice fields, all located within 250 km of the coastline. Investigated ice fields include two meteorite traps — the Allan Hills Icefield and the Frontier Mountain meteorite fields. Antarctic meteorite traps are sustained by very specific glaciological conditions — in particular, only moderate changes in ice thickness over time. The sub-ice topography of these fields was determined by radar measurements and reveals a former, very different glaciological regime, which is interpreted as being associated with glacial processes, operative during the late Tertiary. Field evidence for a hypsithermal event during the Holocene is presented. |
format |
Article in Journal/Newspaper |
author |
Delisle, G. |
author_facet |
Delisle, G. |
author_sort |
Delisle, G. |
title |
Global change, Antarctic meteorite traps and the East Antarctic ice sheet |
title_short |
Global change, Antarctic meteorite traps and the East Antarctic ice sheet |
title_full |
Global change, Antarctic meteorite traps and the East Antarctic ice sheet |
title_fullStr |
Global change, Antarctic meteorite traps and the East Antarctic ice sheet |
title_full_unstemmed |
Global change, Antarctic meteorite traps and the East Antarctic ice sheet |
title_sort |
global change, antarctic meteorite traps and the east antarctic ice sheet |
publisher |
Cambridge University Press (CUP) |
publishDate |
1993 |
url |
http://dx.doi.org/10.1017/s0022143000016051 https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0022143000016051 |
long_lat |
ENVELOPE(159.667,159.667,-76.717,-76.717) ENVELOPE(160.333,160.333,-72.983,-72.983) |
geographic |
Antarctic Victoria Land East Antarctic Ice Sheet Allan Hills Frontier Mountain |
geographic_facet |
Antarctic Victoria Land East Antarctic Ice Sheet Allan Hills Frontier Mountain |
genre |
Antarc* Antarctic Antarctica Ice cap Ice Sheet Journal of Glaciology Victoria Land |
genre_facet |
Antarc* Antarctic Antarctica Ice cap Ice Sheet Journal of Glaciology Victoria Land |
op_source |
Journal of Glaciology volume 39, issue 132, page 397-408 ISSN 0022-1430 1727-5652 |
op_doi |
https://doi.org/10.1017/s0022143000016051 |
container_title |
Journal of Glaciology |
container_volume |
39 |
container_issue |
132 |
container_start_page |
397 |
op_container_end_page |
408 |
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1792506840966234112 |