TY - JOUR
T1 - Seasonal oceanic variability on meso- and submesoscales
T2 - a turbulence perspective
AU - Galperin, Boris
AU - Sukoriansky, Semion
AU - Qiu, Bo
N1 - Funding Information:
Partial funding was provided by the NASA/NOAA Ocean Surface Topography Science Team. BG received partial support through a University of South Florida Nexus Initiative (UNI) Award. SS received partial support from the Israel Science Foundation grant no. 408/15. BQ received support from NASA Grant NNX17AH33G.
Publisher Copyright:
© 2021, Springer-Verlag GmbH, DE part of Springer Nature.
PY - 2021/4/1
Y1 - 2021/4/1
N2 - Seasonal variability of the upper ocean on meso- and submesoscales is investigated in the framework of the quasi-normal scale elimination theory, or QNSE. The longitudinal and transverse velocity spectra in this theory have a bi-component structure comprised of the Coriolis and Kolmogorov-like branches that are identified with meso- and submesoscales, respectively. For the former, spectral amplitudes are determined by the Coriolis parameter, f, while for the latter, the amplitudes are quantified in terms of the energy flux, πε, proceeding from larger to smaller scales. This flux can be identified with the effective submesoscale dissipation. The Kolmogorov and Coriolis subranges are delineated at a length scale Lc that marks a crossover between the respective spectra. The theoretical spectra agree well with those obtained in many observational campaigns. In phase with the seasonal variations of the intensities of instabilities and turbulence, the magnitudes of πε and Lc increase in winter and decrease in summer. Mirroring these changes, the bi-component structure of the kinetic energy spectra changes with seasons and renders meaningless the characterization of their seasonal variability in terms of a single slope. The theoretical results are validated against the data collected in Oleander, LatMix and North-Western Pacific observations.
AB - Seasonal variability of the upper ocean on meso- and submesoscales is investigated in the framework of the quasi-normal scale elimination theory, or QNSE. The longitudinal and transverse velocity spectra in this theory have a bi-component structure comprised of the Coriolis and Kolmogorov-like branches that are identified with meso- and submesoscales, respectively. For the former, spectral amplitudes are determined by the Coriolis parameter, f, while for the latter, the amplitudes are quantified in terms of the energy flux, πε, proceeding from larger to smaller scales. This flux can be identified with the effective submesoscale dissipation. The Kolmogorov and Coriolis subranges are delineated at a length scale Lc that marks a crossover between the respective spectra. The theoretical spectra agree well with those obtained in many observational campaigns. In phase with the seasonal variations of the intensities of instabilities and turbulence, the magnitudes of πε and Lc increase in winter and decrease in summer. Mirroring these changes, the bi-component structure of the kinetic energy spectra changes with seasons and renders meaningless the characterization of their seasonal variability in terms of a single slope. The theoretical results are validated against the data collected in Oleander, LatMix and North-Western Pacific observations.
KW - 92.10.Ei Coriolis effects
KW - 92.10.Lq Turbulence, diffusion, and mixing processes in oceanography
KW - 92.10.ak Eddies and mesoscale processes
UR - http://www.scopus.com/inward/record.url?scp=85101802266&partnerID=8YFLogxK
U2 - 10.1007/s10236-021-01444-1
DO - 10.1007/s10236-021-01444-1
M3 - Article
AN - SCOPUS:85101802266
VL - 71
SP - 475
EP - 489
JO - Ocean Dynamics
JF - Ocean Dynamics
SN - 1616-7341
IS - 4
ER -