Circulation and water masses beneath the northern Ronne Ice Shelf, Antarctica
We present oceanographic data from beneath the northern Ronne Ice Shelf. The data were collected during the austral summer of 2002–2003 from four sites located near the ice front in the Ronne Depression. They consist of conductivity-temperature-depth (CTD) profiles and time series from moored instru...
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American Geophysical Union
2004
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ftnerc:oai:nora.nerc.ac.uk:12320 2023-05-15T13:45:11+02:00 Circulation and water masses beneath the northern Ronne Ice Shelf, Antarctica Nicholls, Keith W. Makinson, Keith Østerhus, Svein 2004 http://nora.nerc.ac.uk/id/eprint/12320/ unknown American Geophysical Union Nicholls, Keith W. orcid:0000-0002-2188-4509 Makinson, Keith orcid:0000-0002-5791-1767 Østerhus, Svein. 2004 Circulation and water masses beneath the northern Ronne Ice Shelf, Antarctica. Journal of Geophysical Research, 109 (C12), C12017. 11, pp. https://doi.org/10.1029/2004JC002302 <https://doi.org/10.1029/2004JC002302> Marine Sciences Glaciology Publication - Article PeerReviewed 2004 ftnerc https://doi.org/10.1029/2004JC002302 2023-02-04T19:27:55Z We present oceanographic data from beneath the northern Ronne Ice Shelf. The data were collected during the austral summer of 2002–2003 from four sites located near the ice front in the Ronne Depression. They consist of conductivity-temperature-depth (CTD) profiles and time series from moored instruments that vary in length from 9 to 20 weeks. A strong, tidally modulated inflow of relatively fresh water was found at the eastern margin of the Ronne Depression. This low-density inflow powers high basal melt rates that are responsible for a substantially thinned area of ice shelf. A northward flow of Ice Shelf Water along the western margin of the depression (the Antarctic Peninsula coast) was inferred from the CTD data. From the new CTD and current meter data, and from published results from cruises along the ice front, we suggest that the flows at the margins of the Ronne Depression establish east-west density gradients that drive an anticyclonic circulation within the depression. The barotropic component of the circulation forms a gyre of strength 5 × 105 m3 s−1 and occupies a bowl in the field of water column thickness in the northern portion of the depression. All water masses sampled had temperatures below the surface freezing point and are therefore classified as Ice Shelf Water. The relatively complex nature of the oceanographic regime in the Ronne Depression is overlain by a seasonal variability that is hinted at by the available time series, probably explaining the apparent absence of inflowing HSSW at the time of the measurements. Article in Journal/Newspaper Antarc* Antarctic Antarctic Peninsula Antarctica Antarctica Journal Ice Shelf Ronne Ice Shelf Natural Environment Research Council: NERC Open Research Archive Antarctic Antarctic Peninsula Austral Ronne Ice Shelf ENVELOPE(-61.000,-61.000,-78.500,-78.500) The Antarctic Journal of Geophysical Research 109 C12 |
institution |
Open Polar |
collection |
Natural Environment Research Council: NERC Open Research Archive |
op_collection_id |
ftnerc |
language |
unknown |
topic |
Marine Sciences Glaciology |
spellingShingle |
Marine Sciences Glaciology Nicholls, Keith W. Makinson, Keith Østerhus, Svein Circulation and water masses beneath the northern Ronne Ice Shelf, Antarctica |
topic_facet |
Marine Sciences Glaciology |
description |
We present oceanographic data from beneath the northern Ronne Ice Shelf. The data were collected during the austral summer of 2002–2003 from four sites located near the ice front in the Ronne Depression. They consist of conductivity-temperature-depth (CTD) profiles and time series from moored instruments that vary in length from 9 to 20 weeks. A strong, tidally modulated inflow of relatively fresh water was found at the eastern margin of the Ronne Depression. This low-density inflow powers high basal melt rates that are responsible for a substantially thinned area of ice shelf. A northward flow of Ice Shelf Water along the western margin of the depression (the Antarctic Peninsula coast) was inferred from the CTD data. From the new CTD and current meter data, and from published results from cruises along the ice front, we suggest that the flows at the margins of the Ronne Depression establish east-west density gradients that drive an anticyclonic circulation within the depression. The barotropic component of the circulation forms a gyre of strength 5 × 105 m3 s−1 and occupies a bowl in the field of water column thickness in the northern portion of the depression. All water masses sampled had temperatures below the surface freezing point and are therefore classified as Ice Shelf Water. The relatively complex nature of the oceanographic regime in the Ronne Depression is overlain by a seasonal variability that is hinted at by the available time series, probably explaining the apparent absence of inflowing HSSW at the time of the measurements. |
format |
Article in Journal/Newspaper |
author |
Nicholls, Keith W. Makinson, Keith Østerhus, Svein |
author_facet |
Nicholls, Keith W. Makinson, Keith Østerhus, Svein |
author_sort |
Nicholls, Keith W. |
title |
Circulation and water masses beneath the northern Ronne Ice Shelf, Antarctica |
title_short |
Circulation and water masses beneath the northern Ronne Ice Shelf, Antarctica |
title_full |
Circulation and water masses beneath the northern Ronne Ice Shelf, Antarctica |
title_fullStr |
Circulation and water masses beneath the northern Ronne Ice Shelf, Antarctica |
title_full_unstemmed |
Circulation and water masses beneath the northern Ronne Ice Shelf, Antarctica |
title_sort |
circulation and water masses beneath the northern ronne ice shelf, antarctica |
publisher |
American Geophysical Union |
publishDate |
2004 |
url |
http://nora.nerc.ac.uk/id/eprint/12320/ |
long_lat |
ENVELOPE(-61.000,-61.000,-78.500,-78.500) |
geographic |
Antarctic Antarctic Peninsula Austral Ronne Ice Shelf The Antarctic |
geographic_facet |
Antarctic Antarctic Peninsula Austral Ronne Ice Shelf The Antarctic |
genre |
Antarc* Antarctic Antarctic Peninsula Antarctica Antarctica Journal Ice Shelf Ronne Ice Shelf |
genre_facet |
Antarc* Antarctic Antarctic Peninsula Antarctica Antarctica Journal Ice Shelf Ronne Ice Shelf |
op_relation |
Nicholls, Keith W. orcid:0000-0002-2188-4509 Makinson, Keith orcid:0000-0002-5791-1767 Østerhus, Svein. 2004 Circulation and water masses beneath the northern Ronne Ice Shelf, Antarctica. Journal of Geophysical Research, 109 (C12), C12017. 11, pp. https://doi.org/10.1029/2004JC002302 <https://doi.org/10.1029/2004JC002302> |
op_doi |
https://doi.org/10.1029/2004JC002302 |
container_title |
Journal of Geophysical Research |
container_volume |
109 |
container_issue |
C12 |
_version_ |
1766215031256514560 |