FN Archimer Export Format
PT J
TI Horizontal dispersion of near-inertial oscillations in a turbulent mesoscale eddy field
BT 
AF KLEIN, Patrice
   SMITH, Stefan Llewellyn
AS 1:;2:;
FF 1:;2:;
C1 IFREMER, Ctr Brest, Lab Phys Oceans, F-29280 Plouzane, France.
   Univ Calif San Diego, Dept Mech & Aerosp Engn, La Jolla, CA 92093 USA.
C2 IFREMER, FRANCE
   UNIV CALIF SAN DIEGO, USA
SI BREST
SE PDG-DRO-DOPS-LPO
IN WOS Ifremer jusqu'en 2018
   copubli-int-hors-europe
IF 1.466
TC 23
UR https://archimer.ifremer.fr/doc/2001/publication-799.pdf
LA English
DT Article
DE ;Refraction;Horizontal dispersion;Wind induced oscillations;Eddy field
AB We study the dispersion of wind-induced near-inertial oscillations (NIOs) in a fully turbulent baroclinic mesoscale eddy field characterized by a continuous wavenumber spectrum. The influence of the eddy field on the horizontal dispersion of the different NIO modes is analyzed using a vertical normal mode expansion. Previous studies have identified two dispersion regimes: trapping and strong dispersion. We examine the modes in physical and spectral space to assess which regime prevails,Numerical and analytical results show the prevalence of a trapping regime. For each NIO mode, there exists a critical horizontal wavenumber. k(c), that separates large-scale NIO structures, where trapping dominates, from the much less energetic small-scale NIO structures, where strong dispersion dominates. The maximum efficiency of dispersion for scales close to k(c) concentrates NIO kinetic energy at these scales.The wavenumber k(c) results from a balance between refraction and dispersion. This balance first occurs at the highest wavenumber. Thereafter. k(c), which has dimensional expression k(c)(2) = pi/(ftR(m)(2)), decreases with time at a rate inversely proportional to the radius of deformation, R-m, of the baroclinic NIO mode considered, As a consequence, at any given time, higher NIO baroclinic mode energy can mostly be found in small-scale negative vorticity structures, such as filaments near sharp vorticity fronts, whereas lower NIO mode energy is concentrated within the core of mesoscale anticyclonic vortices. For large times, a saturation mechanism stops the time-evolution of k(c) at a value close to the peak of the kinetic energy spectrum of the QG flow field.
PY 2001
PD SEP
SO Journal of Marine Research
SN 0022-2402
PU Yale University
VL 59
IS 5
UT 000172709700002
BP 697
EP 723
ID 799
ER

EF