Iceberg calving from the Amery Ice Shelf, East Antarctica
We investigate the iceberg-calving cycle of the Amery Ice Shelf (AIS), East Antarctica, using evidence acquired between 1936 and 2000. The most recent major iceberg-calving event occurred between late 1963 and early 1964, when a large berg totalling about 10 000 km2 in area broke from the ice front....
Published in: | Annals of Glaciology |
---|---|
Main Authors: | , , , |
Format: | Article in Journal/Newspaper |
Language: | English |
Published: |
International Glaciological Society
2002
|
Subjects: | |
Online Access: | https://doi.org/10.3189/172756402781817581 http://ecite.utas.edu.au/24153 |
id |
ftunivtasecite:oai:ecite.utas.edu.au:24153 |
---|---|
record_format |
openpolar |
spelling |
ftunivtasecite:oai:ecite.utas.edu.au:24153 2023-05-15T13:22:04+02:00 Iceberg calving from the Amery Ice Shelf, East Antarctica Fricker, HA Young, NW Allison, I Coleman, R 2002 https://doi.org/10.3189/172756402781817581 http://ecite.utas.edu.au/24153 en eng International Glaciological Society http://dx.doi.org/10.3189/172756402781817581 Fricker, HA and Young, NW and Allison, I and Coleman, R, Iceberg calving from the Amery Ice Shelf, East Antarctica, Annals of Glaciology, 34 pp. 241-246. ISSN 0260-3055 (2002) [Refereed Article] http://ecite.utas.edu.au/24153 Earth Sciences Physical Geography and Environmental Geoscience Glaciology Refereed Article PeerReviewed 2002 ftunivtasecite https://doi.org/10.3189/172756402781817581 2019-12-13T21:05:36Z We investigate the iceberg-calving cycle of the Amery Ice Shelf (AIS), East Antarctica, using evidence acquired between 1936 and 2000. The most recent major iceberg-calving event occurred between late 1963 and early 1964, when a large berg totalling about 10 000 km2 in area broke from the ice front. The rate of forward advance of the ice front is presently 1300-1400 m a 1. At this rate of advance, based on the present ice-front position from recent RADARSAT imagery, it would take 20-25 years to attain the 1963 (pre-calve) position, suggesting that the AIS calving cycle has a period of approximately 60-70 years. Two longitudinal (parallel-to-flow) rifts, approximately 25 km apart at the AIS front, are observed in satellite imagery acquired over the last 14+ years. These rifts have formed at suture zones in the ice shelf, where neighbouring flow-bands have separated in association with transverse spreading. The rifts were 15 km (rift A) and 26 km (rift B) in length in September 2000, and will probably become the sides of a large tabular iceberg (25 km 25 km). A transverse (perpendicular-to-flow) fracture, visible at the upstream end of rift A in 1996, had propagated 6 km towards rift B by September 2000; when it meets rift B the iceberg will calve. A satellite image acquired in 1962 shows an embayment of this size in the AIS front, hence we deduce that this calving pattern also occured during the last calving cycle, and therefore that the calving behaviour of the AIS apparently follows a regular pattern. Article in Journal/Newspaper Amery Ice Shelf Annals of Glaciology Antarc* Antarctica East Antarctica Ice Shelf eCite UTAS (University of Tasmania) Amery ENVELOPE(-94.063,-94.063,56.565,56.565) Amery Ice Shelf ENVELOPE(71.000,71.000,-69.750,-69.750) East Antarctica Annals of Glaciology 34 241 246 |
institution |
Open Polar |
collection |
eCite UTAS (University of Tasmania) |
op_collection_id |
ftunivtasecite |
language |
English |
topic |
Earth Sciences Physical Geography and Environmental Geoscience Glaciology |
spellingShingle |
Earth Sciences Physical Geography and Environmental Geoscience Glaciology Fricker, HA Young, NW Allison, I Coleman, R Iceberg calving from the Amery Ice Shelf, East Antarctica |
topic_facet |
Earth Sciences Physical Geography and Environmental Geoscience Glaciology |
description |
We investigate the iceberg-calving cycle of the Amery Ice Shelf (AIS), East Antarctica, using evidence acquired between 1936 and 2000. The most recent major iceberg-calving event occurred between late 1963 and early 1964, when a large berg totalling about 10 000 km2 in area broke from the ice front. The rate of forward advance of the ice front is presently 1300-1400 m a 1. At this rate of advance, based on the present ice-front position from recent RADARSAT imagery, it would take 20-25 years to attain the 1963 (pre-calve) position, suggesting that the AIS calving cycle has a period of approximately 60-70 years. Two longitudinal (parallel-to-flow) rifts, approximately 25 km apart at the AIS front, are observed in satellite imagery acquired over the last 14+ years. These rifts have formed at suture zones in the ice shelf, where neighbouring flow-bands have separated in association with transverse spreading. The rifts were 15 km (rift A) and 26 km (rift B) in length in September 2000, and will probably become the sides of a large tabular iceberg (25 km 25 km). A transverse (perpendicular-to-flow) fracture, visible at the upstream end of rift A in 1996, had propagated 6 km towards rift B by September 2000; when it meets rift B the iceberg will calve. A satellite image acquired in 1962 shows an embayment of this size in the AIS front, hence we deduce that this calving pattern also occured during the last calving cycle, and therefore that the calving behaviour of the AIS apparently follows a regular pattern. |
format |
Article in Journal/Newspaper |
author |
Fricker, HA Young, NW Allison, I Coleman, R |
author_facet |
Fricker, HA Young, NW Allison, I Coleman, R |
author_sort |
Fricker, HA |
title |
Iceberg calving from the Amery Ice Shelf, East Antarctica |
title_short |
Iceberg calving from the Amery Ice Shelf, East Antarctica |
title_full |
Iceberg calving from the Amery Ice Shelf, East Antarctica |
title_fullStr |
Iceberg calving from the Amery Ice Shelf, East Antarctica |
title_full_unstemmed |
Iceberg calving from the Amery Ice Shelf, East Antarctica |
title_sort |
iceberg calving from the amery ice shelf, east antarctica |
publisher |
International Glaciological Society |
publishDate |
2002 |
url |
https://doi.org/10.3189/172756402781817581 http://ecite.utas.edu.au/24153 |
long_lat |
ENVELOPE(-94.063,-94.063,56.565,56.565) ENVELOPE(71.000,71.000,-69.750,-69.750) |
geographic |
Amery Amery Ice Shelf East Antarctica |
geographic_facet |
Amery Amery Ice Shelf East Antarctica |
genre |
Amery Ice Shelf Annals of Glaciology Antarc* Antarctica East Antarctica Ice Shelf |
genre_facet |
Amery Ice Shelf Annals of Glaciology Antarc* Antarctica East Antarctica Ice Shelf |
op_relation |
http://dx.doi.org/10.3189/172756402781817581 Fricker, HA and Young, NW and Allison, I and Coleman, R, Iceberg calving from the Amery Ice Shelf, East Antarctica, Annals of Glaciology, 34 pp. 241-246. ISSN 0260-3055 (2002) [Refereed Article] http://ecite.utas.edu.au/24153 |
op_doi |
https://doi.org/10.3189/172756402781817581 |
container_title |
Annals of Glaciology |
container_volume |
34 |
container_start_page |
241 |
op_container_end_page |
246 |
_version_ |
1766363154012438528 |