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Surface kinetic energy transfer in surface quasi-geostrophic flows

Published online by Cambridge University Press:  14 May 2008

XAVIER CAPET
Affiliation:
Institute of Geophysics and Planetary Physics, UCLA, Los Angeles CA, USA
PATRICE KLEIN
Affiliation:
Laboratoire de Physique des Océans, IFREMER, CNRS, Plouzané, France
BACH LIEN HUA
Affiliation:
Laboratoire de Physique des Océans, IFREMER, CNRS, Plouzané, France
GUILLAUME LAPEYRE
Affiliation:
Laboratoire de Météorologie Dynamique, IPSL, Ecole Normale Supérieure, CNRS, Paris, France
JAMES C. MCWILLIAMS
Affiliation:
Institute of Geophysics and Planetary Physics, UCLA, Los Angeles CA, USA

Abstract

The relevance of surface quasi-geostrophic dynamics (SQG) to the upper ocean and the atmospheric tropopause has been recently demonstrated in a wide range of conditions. Within this context, the properties of SQG in terms of kinetic energy (KE) transfers at the surface are revisited and further explored. Two well-known and important properties of SQG characterize the surface dynamics: (i) the identity between surface velocity and density spectra (when appropriately scaled) and (ii) the existence of a forward cascade for surface density variance. Here we show numerically and analytically that (i) and (ii) do not imply a forward cascade of surface KE (through the advection term in the KE budget). On the contrary, advection by the geostrophic flow primarily induces an inverse cascade of surface KE on a large range of scales. This spectral flux is locally compensated by a KE source that is related to surface frontogenesis. The subsequent spectral budget resembles those exhibited by more complex systems (primitive equations or Boussinesq models) and observations, which strengthens the relevance of SQG for the description of ocean/atmosphere dynamics near vertical boundaries. The main weakness of SQG however is in the small-scale range (scales smaller than 20–30 km in the ocean) where it poorly represents the forward KE cascade observed in non-QG numerical simulations.

Type
Papers
Copyright
Copyright © Cambridge University Press 2008

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References

REFERENCES

Blumen, W. 1978 Uniform potential vorticity flow: Part I. Theory of wave interactions and two-dimensional turbulence. J. Atmos. Sci. 35, 774783.Google Scholar
Bretherton, F. P. 1966 Critical layer instability in baroclinic flows. Q. J. R. Met. Soc. 92, 325334.Google Scholar
Capet, X., McWilliams, J. C., Molemaker, M. J. & Shchepetkin, A. 2008 Mesoscale to submesoscale transition in the California Current System: Energy balance and flux. J. Phys. Oceanogr. (submitted).CrossRefGoogle Scholar
Celani, A., Cencini, M., Mazzino, A. & Vergassola, M. 2004 Active and passive tracers face to face. New J. Phys. 6, 72.CrossRefGoogle Scholar
Charney, J. G. 1971 Geostrophic turbulence. J. Atmos. Sci. 28, 10871095.2.0.CO;2>CrossRefGoogle Scholar
Hakim, G., Snyder, C. & Muraki, D. 2002 A new surface model for cyclone-anticyclone asymmetry. J. Atmos. Sci. 59, 24052420.2.0.CO;2>CrossRefGoogle Scholar
Held, I., Pierrehumbert, R., Garner, S. & Swanson, K. 1995 Surface quasi-geostrophic dynamics. J. Fluid Mech. 282, 120.Google Scholar
Hoskins, B. & Bretherton, F. 1972 Atmospheric frontogenesis models: Mathematical formulation and solution. J. Atmos. Sci. 29, 1137.2.0.CO;2>CrossRefGoogle Scholar
Hoskins, B., McIntyre, M. & Robertson, A. 1985 One the use and significance of isentropic potential vorticity maps. Q. J. R. Met. Soc. 111, 877946.CrossRefGoogle Scholar
Hua, B. L. & Haidvogel, D. B. 1986 Numerical simulations of the vertical structure of quasi-geostrophic turbulence. J. Atmos. Sci. 43, 29232936.Google Scholar
Isern-Fontanet, J., Chapron, B., Lapeyre, G. & Klein, P. 2006 Potential use of microwave sea surface temperature for the estimation of oceanic currents. Geophys. Res. Lett. 33, L24608.CrossRefGoogle Scholar
Juckes, M. 1994 Quasigeostrophic dynamics of the tropopause. J. Atmos. Sci. 51, 27562768.2.0.CO;2>CrossRefGoogle Scholar
Klein, P., Hua, B. L., Lapeyre, G., Capet, X., Le Gentil, S. & Sasaki, H. 2008 Upper ocean turbulence from high 3-D resolution simulations. J. Phys. Oceanogr. (in press).CrossRefGoogle Scholar
Klein, P., Tréguier, A.-M. & Hua, B. L. 1998 Three-dimensional stirring of thermohaline fronts. J. Mar. Res. 56, 589612.CrossRefGoogle Scholar
LaCasce, J. H. & Mahadevan, A. 2006 Estimating subsurface horizontal and vertical velocities from sea surface temperature. J. Mar. Res. 27, 695721.CrossRefGoogle Scholar
Lapeyre, G. & Klein, P. 2006 Dynamics of the upper oceanic layers in terms of surface quasigeostrophy theory. J. Phys. Oceanogr. 36, 165176.CrossRefGoogle Scholar
Lapeyre, G., Klein, P. & Hua, B. L. 2006 Oceanic restratification forced by surface frontogenesis. J. Phys. Oceanogr. 36, 15771590.CrossRefGoogle Scholar
Le Traon, P. Y., Klein, P., Hua, B. L. & Dibarboure, G. 2007 Do altimeter data agree with interior or surface quasi-geostrophic theory. J. Phys. Oceanogr. (in press).Google Scholar
Molemaker, M. J., McWilliams, J. C. & Capet, X. 2008 Balanced and unbalanced routes to dissipation in an equilibrated eady flow. J. Fluid Mech. (submitted).Google Scholar
Pedlosky, J. 1987 Geophysical Fluid Dynamics. Springer.Google Scholar
Pierrehumbert, R. T., Held, I. M. & Swanson, K. L. 1994 Spectra of local and nonlocal two-dimensional turbulence. Chaos, Solitons Fractals 4, 11111116.Google Scholar
Scott, R. B. & Arbic, B. K. 2007 Spectral energy fluxes in geostrophic turbulence: implications for ocean energetics. J. Phys. Oceanogr. 37, 673688.Google Scholar
Scott, R. & Wang, F. 2005 Direct evidence of an oceanic inverse kinetic energy cascade from satellite altimetry. J. Phys. Oceanogr. 35, 16501666.CrossRefGoogle Scholar
Thomas, L. & Lee, C. 2005 Intensification of ocean fronts by down-front winds. J. Phys. Oceanogr. 35, 10861102.Google Scholar
Tulloch, R. & Smith, K. S. 2006 A new theory for the atmospheric energy spectrum: Depth-limited temperature anomalies at the tropopause. Proc. Natl Acad. Sci. USA 103, 1469014694.CrossRefGoogle ScholarPubMed