English   español  
Please use this identifier to cite or link to this item: http://hdl.handle.net/10261/186849
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:


Changes in Stratospheric Transport and Mixing During Sudden Stratospheric Warmings

AuthorsCámara, Álvaro de la; Abalos, Marta; Hitchcock, Peter B.
KeywordsSudden stratospheric warming
Transport and mixing
Brewer‐Dobson circulation
Effective diffusivity
Stratospheric dynamics
Potential vorticity
Issue Date16-Apr-2018
PublisherAmerican Geophysical Union
CitationJournal of Geophysical Research - Part D - Atmospheres 123(7). 3356-3373 (2018)
AbstractThe extreme disruptions of the wintertime stratospheric circulation during sudden stratospheric warmings (SSW) have large effects on tracer concentrations through alterations in transport. This study analyzes the changes in residual circulation and isentropic mixing associated with SSWs, by performing composites using reanalysis (European Centre for Medium‐Range Weather Forecasts Re‐Analysis Interim) and simulations of the Whole Atmosphere Community Climate Model. The advective Brewer‐Dobson circulation accelerates around 15 days prior to the wind reversal at 60°N, 10 hPa during the onset of SSWs. Soon afterward, it decelerates, leading to reduced advective transport into the vortex and descent over the pole, which persist for more than 2 months below 30 hPa. The isentropic mixing has a distinct signature in altitude: It is enhanced at the central date of the SSW in the midstratosphere (about 10 hPa or 800 K), and this signal is delayed and more persistent at lower altitudes. It is shown that sufficiently deep SSWs (particularly those related to Polar‐night Jet Oscillation events) have a stronger response in the Brewer‐Dobson circulation and mixing. In particular, both the polar downwelling and the tropical upwelling are anomalously weak in the lower stratosphere for 90 days after the onset of Polar‐night Jet Oscillation events. The redistribution of potential vorticity during the life cycle of SSWs is discussed due to its relevance for the stratospheric circulation. It is shown that the diffusive flux of potential vorticity, calculated in equivalent latitude coordinates, remains anomalously high in the lower stratosphere, a feature that is not seen in more conventional advective eddy fluxes across latitude circles.
Publisher version (URL)https://doi.org/10.1002/2017JD028007
Appears in Collections:(IGEO) Artículos
Files in This Item:
File Description SizeFormat 
Changes in Stratospheric Transpor_Camara.pdf7,61 MBAdobe PDFThumbnail
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.