English   español  
Please use this identifier to cite or link to this item: http://hdl.handle.net/10261/15501
Share/Impact:
Statistics
logo share SHARE   Add this article to your Mendeley library MendeleyBASE

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

Spontaneous generation of inertia–gravity waves during the merging of two baroclinic anticyclones

AuthorsPallàs-Sanz, Enric ; Viúdez, Álvaro
Issue DateJan-2008
PublisherAmerican Meteorological Society
Allen Press
CitationJournal of Physical Oceanography 38(1): 213-234 (2008)
AbstractThe spontaneous generation and propagation of short-scale inertia–gravity waves (IGWs) during the merging of two initially balanced (void of IGWs) baroclinic anticyclones is numerically investigated. The IGW generation is analyzed in flows with different potential vorticity (PV) anomaly, numerical diffusion, numerical resolution, vortex aspect ratio, and background rotation. The vertical velocity and its vertical derivative are used to identify the IGWs in the total flow, while the unbalanced flow (the waves) is diagnosed using the optimal PV balance approach. Spontaneous generation of IGWs occurs in all the cases, primarily as emissions of discrete wave packets. The increase of both the vortex strength and vortex extent isotropy enhances the IGW emission. Three possible indicators, or theories, of spontaneous IGW generation are considered, namely, the advection of PV, the material rate of change of the horizontal divergence, and the three-dimensional baroclinic IGW generation analogy of Lighthill sound radiation theory. It is suggested that different mechanisms for spontaneous IGW generation may be at work. One mechanism is related to the advection of PV, with the IGWs in this case having wave fronts similar to the PV isosurfaces in the upper layers, and helical patterns in the deep layers. Trapped IGWs are ubiquitous in the vortex interior and have annular wave front patterns. Another mechanism is related to the spatially coherent motion of preexisting IGWs, which eventually cooperate to produce mean flow, in particular larger-scale horizontal divergence, and therefore larger-scale vertical motion, which in turns triggers the emission of new IGWs.
Description22 pages, 26 figures, 1 table.-- Full-text version available Open Access at: http://www.icm.csic.es/files/oce/almacen/papers/AR-2008-03.pdf
Publisher version (URL)http://dx.doi.org/10.1175/2007JPO3716.1
URIhttp://hdl.handle.net/10261/15501
DOI10.1175/2007JPO3716.1
ISSN0022-3670
Appears in Collections:(ICM) Artículos
Files in This Item:
File Description SizeFormat 
Pallas_et_al_2008.pdf3,46 MBAdobe PDFThumbnail
View/Open
Show full item record
Review this work
 


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