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Ice-front change and iceberg behaviour along Oates and George V Coasts, Antarctica, 1912-96

Abstract

Ice-front change may well be a sensitive indicator of regional climate change. We have studied the western Oates Coast from Cape Kinsey (158°50' E, 69°19' S) to Cape Hudson (153°45' Ε, 68°20' S) and the entire George V Coast, from Cape Hudson to Point Alden (142°02' E, 66°48' S). The glaciers here drain part of the Dome Charlie and Talos Dome areas (640 000 km 2 ). A comparison between various documents, dated several years apart, has allowed an estimate of the surficial ice discharge, the ice-front fluctuation and the iceberg-calving flux during the last 50 years. The ice-front discharge of the studied coast has been estimated at about 90 ± 12 km 3 a −1 in 1989-91, 8.5 km 3 a −1 for western Oates Coast and 82 km 3 a −1 for George V Coast. From 1962-63 to 1973-74 the floating glaciers underwent a net reduction that continued from 1973-74 to 1989-91. On the other hand, from 1989-91 to 1996 the area of floating glaciers increased. Ninnis Glacier Tongue and the western part of Cook Ice Shelf underwent a significant retreat after 1980 and 1947, respectively. Satellite-image analysis of large icebergs has provided information about ice-ocean interaction and the existence of an “iceberg trap” along George V Coast. A first estimate of the mass balance of the drainage basin of Mertz and Ninnis Glaciers shows a value close to zero or slightly negative.

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90° N90° S · 180° W ← longitude → 180° E
Source-reported bounding extent: -71.98576361185364° to -64.7979028899482° latitude; 126.64015855368393° to 165.3337036278141° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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BibTeXRIS

M. Frezzotti, A. Cimbelli, J.G. Ferrigno. 2017-01-20. Ice-front change and iceberg behaviour along Oates and George V Coasts, Antarctica, 1912-96. https://doi.org/10.3189/1998aog27-1-643-650

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