[Parameters: Topic='ATMOSPHERE', Term='ATMOSPHERIC WINDS', Variable_Level_1='UPPER LEVEL WINDS']
The Role of Katabatic Outflow in Maintaining the Upper Level Antarctic Winter VortexEntry ID: ASAC_692
Abstract: The data set associated with this project is a long simulation from a global climate model, with data saved every 6 hours. Also part of the simulated atmospheric data in the project is the results of sensitivity studies which were designed to assess the impact of changes in Antarctic katabatic flow. Among these are simulated data with enhanced surface friction, and with the
removal of ... Antarctic topography.
From the abstract of the referenced paper:
The results of some published studies have been interpreted to suggest that transports associated with the intense katabatic flow field over the Antarctic continent are important factors influencing the development of the upper level winter vortex over the continent. Some of these studies have been rather simplistic and their results may have been taken out of context.
We have undertaken some experiments with a model which includes the effects of many feedbacks and synoptic forcing. In this model we have artificially weakened the katabatic flow and assessed the impact on the upper-level vortex. We have effected this weakening by:
1) 'removing' the Antarctic topography, and
2) increasing the surface momentum drag coefficient over Antarctica.
We find a weakened upper-level vortex circulation in the no-topography experiment but a strengthened vortex in the increased drag experiment. The difference in response can be traced to the nature of the reaction of the tropospheric thermal field. Our results indicate that there is no simple, unambiguous relationship between the strength of the katabatic flow and the depth of the upper-level vortex.
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Start Date: 1993-09-30Stop Date: 1995-03-31
ISO Topic Category
Quality Values provided in temporal coverage are approximate only.
Access Constraints A pdf copy of the referenced paper is available for download from the provided URL.
Use Constraints This data set conforms to the PICCCBY Attribution License
Please follow instructions listed in the citation reference at the provided URL when using these data.
Data Set Progress
Distribution Media: HTTP
Distribution Size: 252 kb
Distribution Format: pdf
Role: TECHNICAL CONTACT
Phone: +61 3 9344 7216
Fax: +61 3 9344 7761
Email: simmonds at unimelb.edu.au
University of Melbourne School of Earth Sciences
Province or State: Victoria
Postal Code: 3052
Role: DIF AUTHOR
Phone: +61 3 6232 3244
Fax: +61 3 6232 3351
Email: dave.connell at aad.gov.au
Australian Antarctic Division 203 Channel Highway
Province or State: Tasmania
Postal Code: 7050
Simmonds I., Law R. (1995) Do low-level winds over Antarctica play a role in maintaining the upper-level low? Abstracts Volume, Australian Meteorological and Oceanographic Society Conference, Lorne, Australia, 20-22 February, 1995 115
Creation and Review Dates
DIF Creation Date: 2000-07-28
Last DIF Revision Date: 2012-09-20