Hostname: page-component-cd9895bd7-fscjk Total loading time: 0 Render date: 2024-12-19T18:09:38.186Z Has data issue: false hasContentIssue false

On the spacing of meandering jets in the strong-stair limit

Published online by Cambridge University Press:  11 November 2021

R.K. Scott*
Affiliation:
School of Mathematics and Statistics, University of St Andrews, North Haugh, St Andrews KY16 9SS, UK
B.H. Burgess
Affiliation:
School of Mathematics and Statistics, University of St Andrews, North Haugh, St Andrews KY16 9SS, UK
D.G. Dritschel
Affiliation:
School of Mathematics and Statistics, University of St Andrews, North Haugh, St Andrews KY16 9SS, UK
*
Email address for correspondence: [email protected]

Abstract

Based on an assumption of strongly inhomogeneous potential vorticity mixing in quasi-geostrophic $\beta$-plane turbulence, a relation is obtained between the mean spacing of latitudinally meandering zonal jets and the total kinetic energy of the flow. The relation applies to cases where the Rossby deformation length is much smaller than the Rhines scale, in which kinetic energy is concentrated within the jet cores. The relation can be theoretically achieved in the case of perfect mixing between regularly spaced jets with simple meanders, and of negligible kinetic energy in flow structures other than in jets. Incomplete mixing or unevenly spaced jets will result in jets being more widely separated than the estimate, while significant kinetic energy outside the jets will result in jets closer than the estimate. An additional relation, valid under the same assumptions, is obtained between the total kinetic and potential energies. In flows with large-scale dissipation, the two relations provide a means to predict the jet spacing based only on knowledge of the energy input rate of the forcing and dissipation rate, regardless of whether the latter takes the form of frictional or thermal damping. Comparison with direct numerical integrations of the forced system shows broad support for the relations, but differences between the actual and predicted jet spacings arise both from the complex structure of jet meanders and the non-negligible kinetic energy contained in the turbulent background and in coherent vortices lying between the jets.

Type
JFM Papers
Copyright
© The Author(s), 2021. Published by Cambridge University Press

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

Footnotes

*

The online version of this article has been updated since original publication. A notice detailing the change has also been published.

References

REFERENCES

Arbic, B.K., Müller, M., Richman, J.G., Shriver, J.F., Morten, A.J., Scott, R.B., Sérazin, G. & Penduff, T. 2014 Geostrophic turbulence in the frequency–wavenumber domain: eddy-driven low-frequency variability. J. Phys. Oceanogr. 44, 20502069.CrossRefGoogle Scholar
Berloff, P., Kamenkovich, I. & Pedlosky, J. 2009 A mechanism of formation of multiple zonal jets in the oceans. J. Fluid Mech. 628, 395425.CrossRefGoogle Scholar
Burgess, B.H. & Scott, R.K. 2018 Robustness of vortex populations in the two-dimensional inverse energy cascade. J. Fluid Mech. 850, 844874.Google Scholar
Chemke, R. & Kaspi, Y. 2015 The latitudinal dependence of atmospheric jet scales and macroturbulent energy cascades. J. Atmos. Sci. 72, 38913907.CrossRefGoogle Scholar
Cho, Y.-K. & Polvani, L.M. 1996 The emergence of jets and vortices in freely-evolving shallow-water turbulence on a sphere. Phys. Fluids 8, 15311540.CrossRefGoogle Scholar
Dritschel, D.G. & McIntyre, M.E. 2008 Multiple jets as PV staircases: the Phillips effect and the resilience of eddy-transport barriers. J. Atmos. Sci. 65, 855874.CrossRefGoogle Scholar
Dunkerton, T.J. & Scott, R.K. 2008 A barotropic model of the angular momentum conserving potential vorticity staircase in spherical geometry. J. Atmos. Sci. 65, 11051136.CrossRefGoogle Scholar
Esler, J.G. 2008 The turbulent equilibration of an unstable baroclinic jet. J. Fluid Mech. 599, 241268.CrossRefGoogle Scholar
Galperin, B. & Read, P.L. 2019 Zonal Jets; Phenomenology, Genesis, and Physics. Cambridge University Press.CrossRefGoogle Scholar
Galperin, B., Sukoriansky, S., Young, R.M.B., Chemke, R., Kaspi, Y., Read, P.L. & Dikovskaya, N. 2019 Barotropic and zonostrophic turbulence. In Zonal Jets: Phenomenology, Genesis, and Physics (ed. B. Galperin & P.L. Read), pp. 220–237. Cambridge University Press.Google Scholar
Heimpel, M., Gastine, T. & Wicht, J. 2016 Simulation of deep-seated zonal jets and shallow vortices in gas giant atmospheres. Nat. Geosci. 9, 1923.Google Scholar
Kitamura, Y. & Ishioka, K. 2007 Equatorial jets in decaying shallow-water turbulence on a rotating sphere. J. Atmos. Sci. 64, 33403353.CrossRefGoogle Scholar
Liu, J. & Schneider, T. 2015 Scaling of off-equatorial jets in giant planet atmospheres. J. Atmos. Sci. 72, 389408.Google Scholar
Maltrud, M.E. & Vallis, G.K. 1991 Energy spectra and coherent structures in forced two-dimensional and beta-plane turbulence. J. Fluid Mech. 228, 321342.Google Scholar
Marcus, P.S. 1993 Jupiter's great red spot and other vortices. Ann. Rev. Astron. Astrophys. 31, 523573.CrossRefGoogle Scholar
McIntyre, M.E. 1982 How well do we understand the dynamics of stratospheric warmings? J. Met. Soc. Japan 60, 3765. Special issue in commemoration of the centennial of the Meteorological Society of Japan, ed. K. Ninomiya.CrossRefGoogle Scholar
Okuno, A. & Masuda, A. 2003 Effect of horizontal divergence on the geostrophic turbulence on a beta-plane: suppression of the Rhines effect. Phys. Fluids 15, 5665.CrossRefGoogle Scholar
Olson, D.B. 1991 Rings in the ocean. Annu. Rev. Earth Planet. Sci. 19, 283311.CrossRefGoogle Scholar
Panetta, R.L. 1993 Zonal jets in wide baroclinically unstable regions: persistence and scale selection. J. Atmos. Sci. 50, 20732106.Google Scholar
Pedlosky, J. 1979 Geophysical Fluid Dynamics. Springer-Verlag.CrossRefGoogle Scholar
Peltier, W.R. & Stuhne, G.R. 2002 The upscale turbulent cascade: shear layers, cyclones and gas giant bands. In Meteorology at the Millennium (ed. R.P. Pierce). Academic Press.Google Scholar
Rhines, P.B. 1975 Waves and turbulence on a beta-plane. J. Fluid Mech. 69, 417443.CrossRefGoogle Scholar
Robert, L., Rivière, G. & Codron, F. 2017 Positive and negative eddy feedbacks acting on midlatitude jet variability in a three-level quasigeostrophic model. J. Atmos. Sci. 74, 16351649.Google Scholar
Scott, R.K. & Dritschel, D.G. 2012 The structure of zonal jets in geostrophic turbulence. J. Fluid Mech. 711, 576598.Google Scholar
Scott, R.K. & Dritschel, D.G. 2013 Halting scale and energy equilibration in two-dimensional quasigeostrophic turbulence. J. Fluid Mech. 721, R4.CrossRefGoogle Scholar
Scott, R.K. & Dritschel, D.G. 2019 Zonal jet formation by potential vorticity mixing at large and small scales. In Zonal Jets: Phenomenology, Genesis, and Physics (ed. B. Galperin & P.L. Read), pp. 240–248. Cambridge University Press.Google Scholar
Scott, R.K. & Polvani, L.M. 2007 Forced-dissipative shallow water turbulence on the sphere and the atmospheric circulation of the gas planets. J. Atmos. Sci. 64, 31583176.CrossRefGoogle Scholar
Scott, R.K. & Polvani, L.M. 2008 Equatorial superrotation in shallow atmospheres. Geophys. Res. Lett. 35, L24202.Google Scholar
Scott, R.K. & Tissier, A.-S. 2012 The generation of zonal jets by large-scale mixing. Phys. Fluids 24, 126601.Google Scholar
Shevchenko, I. & Berloff, P. 2015 Multi-layer quasi-geostrophic ocean dynamics in eddy-resolving regimes. Ocean Model. 394, 114.Google Scholar
Smith, K.S., Boccaletti, G., Henning, C.C., Marinov, I., Tam, C.Y., Held, I.M. & Vallis, G.K. 2002 Turbulent diffusion in the geostrophic inverse cascade. J. Fluid Mech. 469, 1348.Google Scholar
Sukoriansky, S., Dikovskaya, N. & Galperin, B. 2007 On the arrest of inverse energy cascade and the Rhines scale. J. Atmos. Sci. 64, 33123327.Google Scholar
Theiss, J. 2004 Equatorward energy cascade, critical latitude, and the predominance of cyclonic vortices in geostrophic turbulence. J. Phys. Oceanogr. 34, 16631678.Google Scholar
Thompson, A.F. & Young, W.R. 2007 Two-layer baroclinic eddy heat fluxes: zonal flows and energy balance. J. Atmos. Sci. 64, 32143231.Google Scholar
Tran, C.V. & Dritschel, D.G. 2006 Impeded inverse energy transfer in the Charney-Hasegawa-Mima model of quasi-geostrophic flows. J. Fluid Mech. 551, 435443.CrossRefGoogle Scholar
Vallis, G.K. 2006 Atmospheric and Oceanic Fluid Dynamics. Cambridge University Press.Google Scholar
Vallis, G.K. & Maltrud, M.E. 1993 Generation of mean flows on a beta plane and over topography. J. Phys. Oceanogr. 23, 13461362.2.0.CO;2>CrossRefGoogle Scholar
Williams, G.P. 1978 Planetary circulations: 1. Barotropic representation of Jovian and terrestrial turbulence. J. Atmos. Sci. 35, 13991424.Google Scholar
Williams, P.D. & Kelsall, C.W. 2015 The dynamics of baroclinic zonal jets. J. Atmos. Sci. 72, 11371151.Google Scholar
Zurita-Gotor, P., Blanco-Fuentes, J. & Gerber, E.P. 2014 The impact of baroclinic eddy feedback on the persistence of jet variability in the two-layer model. J. Atmos. Sci. 71, 410429.Google Scholar