Abstract
The path of the Antarctic Polar Front (PF) is mapped using satellite sea surface temperature data from the NOAA/NASA Pathfinder program. The mean path and variability of the PF are strongly influenced by bathymetry. Meandering intensity is weaker where the bathymetry is steeply sloped and increases in areas where the bottom is relatively flat. There is an inverse relationship between meandering intensity and both the width of the front and the change in temperature across it There is a persistent, large separation between the surface and subsurface expressions of the PF at Ewing Bank on the Falkland Plateau.
Highlights
The large changesin seasurfaceheightdetectedby terms of air-sea fluxesand the heat and salt budgetsof the the two-jet modelwould likely be associatedwith the subsur
PF mark the location where Antarctic surface waters descend In openoceanareasthe planetaryvorticityismuchlargerthan rapidly,suchasthe pointwherethe minimumpotentialtem- the relativevorticity,and mean potentialvorticitycan be apperaturelayer sinksbelow200 m depth [Deacon,1933, 1937; proximatedasf/H
Paper number97JC01705. 0148-0227/97/97JC- 01705509.00 gram data sethashigh-resolutionglobalSST coveragederived from the advancedveryhighresolutionradiometer(AVHRR)
Summary
We have used the strongsea surfacetemperature(SST) gradientat the PF to map its surfaceexpressionin the region 90ø-20øWover the 2 year period 1987-1988.Similarmapping. EwingBank.Severalrecentstudieshaveplacedthe subsurface In Figure 4 the area from 50ø to 45øW hasbeen divided into expressionof the PF as crossingthe Falkland Plateau and two columns with data from north and south of the north flowingeastwardalongthe northsideof EwingBank [Peterson ScotiaRidge(clearlytwo differentdomainss, eeFigures and and Whitworth1, 989;Gille, 1994;Orsiet al., 1995].It is in this 2) presentedseparately. The meanplanetarypotentialvorticityalongthe meanpath of the PF wascalculatedat eachlongitudewithin a moving2ø longitudewide window.In Plate 3 the planetarypotentialvorticityfield andmeanPF path from Plate 2 are reproduced,but alongeachlongitudinaline a relativelynarrowrangeof planetary potential vorticity values, consistingof the calculated meanplanetarpyotentiavlorticitvyalueof__1+0-9 m- s-, has been set to white This narrow range of planetarypotential vorticityvaluescan be consideredas encompassinga local regionof quasi-uniformplanetarypotentialvorticity(the mean valueof __-+--5%).The PF isfree to meanderwithinthisregion whilemaintaininga relativelyconstantplanetarypote.
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
