English   español  
Please use this identifier to cite or link to this item: http://hdl.handle.net/10261/15549
logo share SHARE logo core CORE   Add this article to your Mendeley library MendeleyBASE

Visualizar otros formatos: MARC | Dublin Core | RDF | ORE | MODS | METS | DIDL
Exportar a otros formatos:


The persistence of balance in geophysical flows

AuthorsDritschel, David G.; Viúdez, Álvaro
Issue Date3-Jan-2007
PublisherCambridge University Press
CitationJournal of Fluid Mechanics 570: 365-383 (2007)
AbstractRotating stably stratified geophysical flows can exhibit a near ‘balanced’ evolution controlled by the conservative advection of a single scalar quantity, the potential vorticity (PV). This occurs frequently in the Earth's atmosphere and oceans where motions tend to be weak compared with the background planetary rotation and where stratification greatly inhibits vertical motion. Under these circumstances, both high-frequency acoustic waves and lower-frequency inertia–gravity waves (IGWs) contribute little to the flow evolution compared with the even-lower-frequency advection of PV. Moreover, this ‘slow’ PV-controlled balanced evolution appears unable to excite these higher-frequency waves in any significant way – i.e. balance persists.
The present work pushes the limits of balance by systematically exploring the evolution of a range of highly nonlinear flows in which motions are comparable with the background rotation. These flows do not possess a frequency separation between PV advection and IGWs. Nonetheless, the flows exhibit a remarkable persistence of balance. Even when flows are not initialized to minimize the amount of IGWs initially present, and indeed even when flows are deliberately seeded with significant IGW amplitudes, the flow evolution – over many inertial periods (days) – remains strongly controlled by PV advection
Description19 pages, 16 figures
Publisher version (URL)http://dx.doi.org/10.1017/S0022112006002990
Appears in Collections:(ICM) Artículos
Files in This Item:
There are no files associated with this item.
Show full item record
Review this work

Related articles:

WARNING: Items in Digital.CSIC are protected by copyright, with all rights reserved, unless otherwise indicated.