An extreme wind event at Casey Station, Antarctica
Model output, satellite data, and in situ observations are used to investigate the conditions that gave rise to an extreme wind event at the Australian Casey Station (66.27°S, 110.53°E) on the coast of East Antarctica. The event took place over the period March 20–22, 1992, and resulted in Casey Sta...
Published in: | Journal of Geophysical Research: Atmospheres |
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American Geophysical Union
2001
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ftnerc:oai:nora.nerc.ac.uk:20315 2023-05-15T13:45:12+02:00 An extreme wind event at Casey Station, Antarctica Turner, John Lachlan-Cope, Tom A. Marshall, Gareth J. Pendlebury, Stephen Adams, Neil 2001 http://nora.nerc.ac.uk/id/eprint/20315/ https://doi.org/10.1029/2000JD900544 unknown American Geophysical Union Turner, John orcid:0000-0002-6111-5122 Lachlan-Cope, Tom A. orcid:0000-0002-0657-3235 Marshall, Gareth J. orcid:0000-0001-8887-7314 Pendlebury, Stephen; Adams, Neil. 2001 An extreme wind event at Casey Station, Antarctica. Journal of Geophysical Research, 106 (D7). 7291-7311. https://doi.org/10.1029/2000JD900544 <https://doi.org/10.1029/2000JD900544> Publication - Article PeerReviewed 2001 ftnerc https://doi.org/10.1029/2000JD900544 2023-02-04T19:32:47Z Model output, satellite data, and in situ observations are used to investigate the conditions that gave rise to an extreme wind event at the Australian Casey Station (66.27°S, 110.53°E) on the coast of East Antarctica. The event took place over the period March 20–22, 1992, and resulted in Casey Station's highest ever wind gust for March (66.9 m s−1, 130 knots) and 10 m mean winds of near 50 m s−1. The event occurred when a deep low was located just north of the coast and there was high surface pressure inland. The rapid deepening of the low took place within a strong baroclinic zone lying north-south between a cold trough and a ridge bringing very warm air southward. A conceptual model is proposed for the very strong winds experienced at Casey Station. Key elements of the model are (1) a synoptic-scale high-low pressure couplet, providing a strengthening pressure gradient; (2) entrainment of radiatively cooled air by the supercritical synoptic gradient, leading to downslope flow; (3) the acceleration of the wind down the lee slope of Law Dome, occurring primarily in response to a topographically induced, long-period, vertically propagating gravity wave; and (4) sources of negative buoyancy, including prestorm radiatively cooled air and, later in the storm, maritime air cooled by heat flux to the ice surface. The topographically induced gravity wave increases the horizontal temperature difference, thus increasing the negative buoyancy of the surface airflow. Article in Journal/Newspaper Antarc* Antarctica Antarctica Journal East Antarctica Natural Environment Research Council: NERC Open Research Archive East Antarctica Casey Station ENVELOPE(110.528,110.528,-66.282,-66.282) Law Dome ENVELOPE(112.833,112.833,-66.733,-66.733) Journal of Geophysical Research: Atmospheres 106 D7 7291 7311 |
institution |
Open Polar |
collection |
Natural Environment Research Council: NERC Open Research Archive |
op_collection_id |
ftnerc |
language |
unknown |
description |
Model output, satellite data, and in situ observations are used to investigate the conditions that gave rise to an extreme wind event at the Australian Casey Station (66.27°S, 110.53°E) on the coast of East Antarctica. The event took place over the period March 20–22, 1992, and resulted in Casey Station's highest ever wind gust for March (66.9 m s−1, 130 knots) and 10 m mean winds of near 50 m s−1. The event occurred when a deep low was located just north of the coast and there was high surface pressure inland. The rapid deepening of the low took place within a strong baroclinic zone lying north-south between a cold trough and a ridge bringing very warm air southward. A conceptual model is proposed for the very strong winds experienced at Casey Station. Key elements of the model are (1) a synoptic-scale high-low pressure couplet, providing a strengthening pressure gradient; (2) entrainment of radiatively cooled air by the supercritical synoptic gradient, leading to downslope flow; (3) the acceleration of the wind down the lee slope of Law Dome, occurring primarily in response to a topographically induced, long-period, vertically propagating gravity wave; and (4) sources of negative buoyancy, including prestorm radiatively cooled air and, later in the storm, maritime air cooled by heat flux to the ice surface. The topographically induced gravity wave increases the horizontal temperature difference, thus increasing the negative buoyancy of the surface airflow. |
format |
Article in Journal/Newspaper |
author |
Turner, John Lachlan-Cope, Tom A. Marshall, Gareth J. Pendlebury, Stephen Adams, Neil |
spellingShingle |
Turner, John Lachlan-Cope, Tom A. Marshall, Gareth J. Pendlebury, Stephen Adams, Neil An extreme wind event at Casey Station, Antarctica |
author_facet |
Turner, John Lachlan-Cope, Tom A. Marshall, Gareth J. Pendlebury, Stephen Adams, Neil |
author_sort |
Turner, John |
title |
An extreme wind event at Casey Station, Antarctica |
title_short |
An extreme wind event at Casey Station, Antarctica |
title_full |
An extreme wind event at Casey Station, Antarctica |
title_fullStr |
An extreme wind event at Casey Station, Antarctica |
title_full_unstemmed |
An extreme wind event at Casey Station, Antarctica |
title_sort |
extreme wind event at casey station, antarctica |
publisher |
American Geophysical Union |
publishDate |
2001 |
url |
http://nora.nerc.ac.uk/id/eprint/20315/ https://doi.org/10.1029/2000JD900544 |
long_lat |
ENVELOPE(110.528,110.528,-66.282,-66.282) ENVELOPE(112.833,112.833,-66.733,-66.733) |
geographic |
East Antarctica Casey Station Law Dome |
geographic_facet |
East Antarctica Casey Station Law Dome |
genre |
Antarc* Antarctica Antarctica Journal East Antarctica |
genre_facet |
Antarc* Antarctica Antarctica Journal East Antarctica |
op_relation |
Turner, John orcid:0000-0002-6111-5122 Lachlan-Cope, Tom A. orcid:0000-0002-0657-3235 Marshall, Gareth J. orcid:0000-0001-8887-7314 Pendlebury, Stephen; Adams, Neil. 2001 An extreme wind event at Casey Station, Antarctica. Journal of Geophysical Research, 106 (D7). 7291-7311. https://doi.org/10.1029/2000JD900544 <https://doi.org/10.1029/2000JD900544> |
op_doi |
https://doi.org/10.1029/2000JD900544 |
container_title |
Journal of Geophysical Research: Atmospheres |
container_volume |
106 |
container_issue |
D7 |
container_start_page |
7291 |
op_container_end_page |
7311 |
_version_ |
1766217051738734592 |