Saturn’s Northern Hemisphere Ribbon: Simulations and Comparison with the Meandering Gulf Stream
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Voyager observations of Saturn in 1980–81 discovered a wavy feature engirdling the planet at 47°N planetographic latitude. Its latitude coincides with that of an eastward jet stream, which is the second fastest on Saturn after the equatorial jet. The 47°N jet’s wavy morphology is unique among the known atmospheric jets on the gas giant planets. Since the Voyagers, it has been seen in every high-resolution image of this latitude for over 25 years and has been termed the Ribbon. The Ribbon has been interpreted as a dynamic instability in the jet stream. This study tests this interpretation and uses forward modeling to explore the observed zonal wind profile’s stability properties. Unforced, initial-value numerical experiments are performed to examine the nonlinear evolution of the jet stream. Parameter variations show that an instability occurs when the 47°N jet causes reversals in the potential vorticity (PV) gradient, which constitutes a violation of the Charney–Stern stability criterion. After the initial instability development, the simulations demonstrate that the instability’s amplitude nonlinearly saturates to a constant when the eddy generation by the instability is balanced by the destruction of the eddies. When the instability saturates, the zonal wind profile approaches neutral stability according to Arnol’d’s second criterion, and the jet’s path meanders in a Ribbon-like manner. It is demonstrated that the meandering of the 47°N jet occurs over a range of tropospheric static stability and background wind speed. The results here show that a nonlinearly saturated shear instability in the 47°N jet is a viable mechanism to produce the Ribbon morphology. Observations do not yet have the temporal coverage to confirm the creation and destruction of eddies, but these simulations predict that this is actively occurring in the Ribbon region. Similarities exist between the behaviors found in this model and the dynamics of PV fronts studied in the context of meandering western boundary currents in Earth’s oceans. In addition, the simulations capture the nonlinear aspects of a new feature discovered by the Cassini Visual and Infrared Mapping Spectrometer (VIMS), the String of Pearls, which resides in the equatorward tip of the 47°N jet. The Explicit Planetary Isentropic Coordinate (EPIC) model is used herein.
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For jet centers at 35° and 30°, the jet equilibrates in a state more reminiscent of the Ribbon morphology than the Hexagon.
“For the cases when the jet center is placed at 35 ° and 30 ° , the jet equilibrates in a state that is more reminiscent of the morphology of the Ribbon ( Godfrey & Moore 1986; Sayanagi et al. 2010 ) than that of the Hexagon.”
From MEANDERING SHALLOW ATMOSPHERIC JET AS A MODEL OF SATURNʼS NORTH-POLAR HEXAGON (2015) · cites this paper as Sayanagi et al. 2010
Cites
Peixoto, J. P., & Oort, A. H. (1992) · Medical Entomology and Zoology · Cited by 1,888 · see citing works
Available potential energy and the maintenance of the general circulation.
Lorenz, E. N. (1955) · Tellus A Dynamic Meteorology and Oceanography · doi:10.3402/tellusa.v7i2.8796 · Cited by 1,227 · see citing works
Peixoto, J. P., Oort, A. H., Covey, C., & Taylor, K. E. (1992) · Physics Today · doi:10.1063/1.2809772 · Cited by 1,197 · see citing works
A New Look at the Saturn System: The Voyager 2 Images
Smith, B. A., Soderblom, L., Batson, R., Bridges, P., Inge, J., Masursky, H., Shoemaker, E., Beebe, R., Boyce, J., Briggs, G., et al. (1982) · Science · doi:10.1126/science.215.4532.504 · Cited by 848 · see citing works
Self-citationOn the North Atlantic Circulation
Schmitz, W. J., & McCartney, M. S. (1993) · Reviews of Geophysics · doi:10.1029/92rg02583 · Cited by 763 · see citing works
Generation of Mean Flows and Jets on a Beta Plane and over Topography
Vallis, G. K., & Maltrud, M. E. (1993) · Journal of Physical Oceanography · doi:10.1175/1520-0485(1993)023 · Cited by 410 · see citing works
Jovian atmospheric dynamics: an update after Galileo and Cassini
Vasavada, A. R., & Showman, A. P. (2005) · Reports on Progress in Physics · doi:10.1088/0034-4885/68/8/r06 · Cited by 329 · see citing works
Potential Vorticity Distribution in the North Pacific
Talley, L. D. (1988) · Journal of Physical Oceanography · doi:10.1175/1520-0485(1988)018 · Cited by 169 · see citing works
Large Diurnal Sea Surface Temperature Variability: Satellite and In Situ Measurements
Stramma, L., Cornillon, P., Weller, R. A., Price, J. F., & Briscoe, M. G. (1986) · Journal of Physical Oceanography · doi:10.1175/1520-0485(1986)016 · Cited by 156 · see citing works
Saturn's Zonal Winds at Cloud Level
Sánchez-Lavega, A. (2000) · Icarus · doi:10.1006/icar.2000.6449 · Cited by 154 · see citing works
Nonlinear Simulations of Jupiter's 5-Micron Hot Spots
Showman, A. P., & Dowling, T. E. (2000) · Science · doi:10.1126/science.289.5485.1737 · Cited by 148 · see citing works
Dynamics of Jovian atmospheres
Dowling, T. (1995) · Annual Review of Fluid Mechanics · doi:10.1146/annurev.fl.27.010195.001453 · Cited by 130 · see citing works
The Explicit Planetary Isentropic-Coordinate (EPIC) Atmospheric Model
Dowling, T. E., Fischer, A. S., Gierasch, P. J., Harrington, J., LeBeau, R. P., & Santori, C. M. (1998) · Icarus · doi:10.1006/icar.1998.5917 · Cited by 128 · see citing works
Interaction between eddies and mean flow in Jupiter’s atmosphere: Analysis of Cassini imaging data.
Salyk, C., Ingersoll, A. P., Lorre, J., Vasavada, A., & Del Genio, A. D. (2006) · Icarus · doi:10.1016/j.icarus.2006.08.007 · Cited by 124 · see citing works
Self-citationTyler, G. L., Eshleman, V. R., Anderson, J. D., Levy, G. S., Lindal, G. F., Wood, G. E., & Croft, T. A. (1982) · Science · doi:10.1126/science.215.4532.553 · Cited by 100 · see citing works
A Generalization of Bernoulli's Theorem
Schär, C. (1993) · Journal of the Atmospheric Sciences · doi:10.1175/1520-0469(1993)050 · Cited by 98 · see citing works
Preliminary report on long-period variations in the transport of the Gulf Stream system
Iselin, C. O. (1940) · doi:10.1575/1912/1048 · Cited by 90 · see citing works
Read, P. L., Gierasch, P. J., Conrath, B. J., Simon, A. A., Fouchet, T., & Yamazaki, Y. H. (2006) · Quarterly Journal of the Royal Meteorological Society · doi:10.1256/qj.05.34 · Cited by 82 · see citing works
Mapping potential vorticity dynamics on saturn: Zonal mean circulation from Cassini and Voyager data
Read, P. L., Conrath, B. J., Fletcher, L. N., Gierasch, P. J., Simon-Miller, A. A., & Zuchowski, L. C. (2009) · Planetary and Space Science · doi:10.1016/j.pss.2009.03.004 · Cited by 82 · see citing works
The Baroclinic Instability of the Open Ocean
Robinson, A. R., & McWilliams, J. C. (1974) · Journal of Physical Oceanography · doi:10.1175/1520-0485(1974)004 · Cited by 79 · see citing works
Evolution of the ENSO Signal over the Indo–Pacific Domain*
Tourre, Y. M., & White, W. B. (1997) · Journal of Physical Oceanography · doi:10.1175/1520-0485(1997)027 · Cited by 77 · see citing works
LeBeau, R., & Dowling, T. E. (1998) · Icarus · doi:10.1006/icar.1998.5918 · Cited by 74 · see citing works
Sromovsky, L. A., Revercomb, H. E., Krauss, R. J., & SUOMI, V. E. (1983) · Journal of Geophysical Research Atmospheres · doi:10.1029/ja088ia11p08650 · Cited by 73 · see citing works
Temporal variation of meandering intensity and domain‐wide lateral oscillations of the Gulf Stream
Lee, T., & Cornillon, P. (1995) · Journal of Geophysical Research Atmospheres · doi:10.1029/95jc01219 · Cited by 67 · see citing works
Saturn eddy momentum fluxes and convection: First estimates from Cassini images.
DELGENIO, A., BARBARA, J., FERRIER, J., INGERSOLL, A., WEST, R., VASAVADA, A., SPITALE, J., & PORCO, C. (2007) · Icarus · doi:10.1016/j.icarus.2007.02.013 · Cited by 65 · see citing works
Self-citationThe EPIC atmospheric model with an isentropic/terrain-following hybrid vertical coordinate
Dowling, T. E., Bradley, M. E., Colón, E., Kramer, J., LeBeau, R., Lee, G. C. H., Mattox, T. I., Morales-Juberías, R., Palotai, C., Parimi, V. K., et al. (2006) · Icarus · doi:10.1016/j.icarus.2006.01.003 · Cited by 57 · see citing works
Self-citationStocker, T. F., & Wright, D. G. (1991) · Journal of Physical Oceanography · doi:10.1175/1520-0485(1991)021 · Cited by 57 · see citing works
Storms and flow reversals at the HEBBLE site
Weatherly, G. L., & Kelley, E. A. (1985) · Marine Geology · doi:10.1016/0025-3227(85)90030-1 · Cited by 57 · see citing works
Cloud features and zonal wind measurements of Saturn's atmosphere as observed by Cassini/VIMS
Choi, D. S., Showman, A. P., & Brown, R. H. (2009) · Journal of Geophysical Research: Planets · doi:10.1029/2008je003254 · Cited by 53 · cited 4× · see citing works
“Choi et al. (2009) measured that the pearls are about 1000 km in diameter each, spaced around 48 in longitude and centered at 408 6 28N latitude.”
BackgroundInfluentialStability of a potential vorticity front: from quasi-geostrophy to shallow water
Boss, E., Paldor, N., & Thompson, L. (1996) · Journal of Fluid Mechanics · doi:10.1017/s0022112096002339 · Cited by 53 · see citing works
The near-surface velocity and potential vorticity structure of the Gulf Stream
Rossby, T., & Zhang, H.-M. (2001) · Journal of Marine Research · doi:10.1357/00222400160497724 · Cited by 51 · see citing works
The Saturnian ribbon feature—A baroclinically unstable model
Godfrey, D. A., & Moore, V. (1986) · Icarus · doi:10.1016/0019-1035(86)90026-6 · Cited by 39 · see citing works
Effects of a large convective storm on Saturn's equatorial jet
Sayanagi, K. M., & Showman, A. P. (2006) · Icarus · doi:10.1016/j.icarus.2006.10.020 · Cited by 31 · see citing works
Self-citationSayanagi, K. M., Showman, A. P., & Dowling, T. E. (2008) · Journal of the Atmospheric Sciences · doi:10.1175/2008jas2558.1 · Cited by 29 · see citing works
Self-citationVertical structure of Jupiter's troposphere from nonlinear simulations of long-lived vortices
Legarreta, J., & Sánchez-Lavega, A. (2008) · Icarus · doi:10.1016/j.icarus.2008.02.018 · Cited by 28 · see citing works
The Influence of Topography on the Stability of Jets
Poulin, F., & Flierl, G. R. (2005) · Journal of Physical Oceanography · doi:10.1175/jpo2719.1 · Cited by 27 · see citing works
Dynamics of the Coastal Transition Zone jet: 2. Nonlinear finite amplitude behavior
Allen, J. S., Walstad, L. J., & Newberger, P. A. (1991) · Journal of Geophysical Research Atmospheres · doi:10.1029/91jc00980 · Cited by 26 · see citing works
Meinen, C. S., Luther, D. S., & Baringer, M. (2008) · Deep Sea Research Part I Oceanographic Research Papers · doi:10.1016/j.dsr.2008.07.010 · Cited by 25 · see citing works
On the theory of thin rotating jets: A quasi‐geostrophic time dependent model
Robinson, A. R., Luyten, J. R., & Flierl, G. R. (1975) · Geophysical Fluid Dynamics · doi:10.1080/03091927509365796 · Cited by 20 · see citing works
Thin jet and contour dynamics models of Gulf Stream meandering
Flierl, G. R. (1999) · Dynamics of Atmospheres and Oceans · doi:10.1016/s0377-0265(99)00006-8 · Cited by 17 · see citing works
Observations of Saturn's ribbon wave 14 years after its discovery
Sanchez-Lavega, A. (2002) · Icarus · doi:10.1006/icar.2002.6864 · Cited by 13 · cited 3× · see citing works
“Despite the hypothesis that the Ribbon arises from dynamic instability, it is a long-lived feature; it is found in Hubble Space Telescope images captured in 1994–95 (Sánchez-Lavega 2002) and it can also be seen in recent Cassini images of Saturn.”
BackgroundInfluentialThe Zoology of Saturn: The Bizarre Features Unveiled by the 5 Micron Eyes of Cassini/VIMS
Momary, T., Baines, K. H., & Cassini (2006) · DPS · Cited by 11 · see citing works
Finite amplitude waves on barotropic shear layers and jets
Meacham, S. P., & Flierl, G. R. (1991) · Geophysical & Astrophysical Fluid Dynamics · doi:10.1080/03091929108219511 · Cited by 4 · see citing works
Vauclair (2004) · doi:10.1175/1520-0485(2004)034
Flagged first, then by citations
3 of the 56 references couldn’t be matched to a known paper.
Cited by
Sorted by citations
Spiga, A., Guerlet, S., Millour, E., Indurain, M., Meurdesoif, Y., Cabanes, S., Dubos, T., Leconte, J., Boissinot, A., Lebonnois, S., et al. (2019) · Icarus · doi:10.1016/j.icarus.2019.07.011 · Cited by 55 · see citing works
The universal aspect ratio of vortices in rotating stratified flows: theory and simulation
Hassanzadeh, P., Marcus, P., & Gal, P. L. (2012) · Journal of Fluid Mechanics · doi:10.1017/jfm.2012.180 · Cited by 44 · see citing works
Constraints on Saturn’s tropospheric general circulation from Cassini ISS images
C, A. D. D. G., & Barbara, J. (2012) · Icarus · doi:10.1016/j.icarus.2012.03.035 · Cited by 36 · see citing works
MEANDERING SHALLOW ATMOSPHERIC JET AS A MODEL OF SATURNʼS NORTH-POLAR HEXAGON
Morales-Juberías, R., Sayanagi, K. M., Simon, A. A., Fletcher, L. N., & Cosentino, R. G. (2015) · The Astrophysical Journal · doi:10.1088/2041-8205/806/1/l18 · Cited by 35 · see citing works
Self-citationSayanagi, K. M., Baines, K. H., Dyudina, U. A., Fletcher, L. N., Sánchez-Lavega, A., & West, R. A. (2018) · Cambridge University Press eBooks · doi:10.1017/9781316227220.012 · Cited by 33 · see citing works
Self-citationCassini Exploration of the Planet Saturn: A Comprehensive Review
Ingersoll, A. P. (2020) · Space Science Reviews · doi:10.1007/s11214-020-00751-1 · Cited by 32 · see citing works
Self-citationCassini ISS observation of Saturn’s String of Pearls
Sayanagi, K. M., Dyudina, U. A., Ewald, S. P., Muro, G. D., & Ingersoll, A. P. (2013) · Icarus · doi:10.1016/j.icarus.2013.10.032 · Cited by 26 · see citing works
Self-citationEmergence of polar-jet polygons from jet instabilities in a Saturn model
Morales-Juberías, R., Sayanagi, K. M., Dowling, T. E., & Ingersoll, A. P. (2011) · Icarus · doi:10.1016/j.icarus.2010.11.006 · Cited by 24 · see citing works
Self-citationHueso, R., Sánchez-Lavega, A., Rojas, J. F., Simon, A. A., Barry, T., Río-Gaztelurrutia, T. D., Antuñano, A., Sayanagi, K. M., Delcroix, M., Fletcher, L. N., et al. (2020) · Icarus · doi:10.1016/j.icarus.2019.113429 · Cited by 20 · see citing works
“Analytical (Godfrey and Moore, 1986) and numerical (Sayanagi et al., 2010) studies of the nature of the ribbon as observed by the Voyagers suggest the wave can be a baroclinic instability.”
BackgroundSelf-citationThe Great Saturn Storm of 2010–2011
Sánchez-Lavega, A., Fischer, G., Fletcher, L. N., Garcia‐Melendo, E., Hesman, B. E., Pérez-Hoyos, S., Sayanagi, K. M., & Sromovsky, L. A. (2018) · Cambridge University Press eBooks · doi:10.1017/9781316227220.013 · Cited by 18 · see citing works
Self-citationSimon, A. A., Wong, M. H., Sromovsky, L. A., Fletcher, L. N., & Fry, P. M. (2022) · Remote Sensing · doi:10.3390/rs14061518 · Cited by 15 · see citing works
Saturn's new ribbons: Cassini observations of planetary waves in Saturn's 42N atmospheric jet
Gunnarson, J. L., Sayanagi, K. M., Blalock, J. J., Fletcher, L. N., Ingersoll, A. P., Dyudina, U. A., Ewald, S. P., & Draham, R. L. (2018) · Geophysical Research Letters · doi:10.1029/2018gl078156 · Cited by 13 · see citing works
Self-citationFlow patterns of Jupiter's south polar region
ROGERS, J. H., Eichstädt, G., Hansen, C. J., Orton, G. S., Momary, T., Casely, A., Adamoli, G., Jacquesson, M., Bullen, R., Peach, D., et al. (2021) · Icarus · doi:10.1016/j.icarus.2021.114742 · Cited by 7 · see citing works
Sankar, R., Klare, C., & Palotai, C. (2021) · Icarus · doi:10.1016/j.icarus.2021.114589 · Cited by 6 · see citing works
Energy Exchanges in Saturn's Polar Regions From Cassini Observations: Eddy‐Zonal Flow Interactions
Read, P. L., Antuñano, A., Colyer, G., Cabanes, S., del Río-Gaztelurrutia, T., & Sánchez-Lavega, A. (2022) · Journal of Geophysical Research Planets · doi:10.1029/2021je006973 · Cited by 6 · see citing works
Hassanzadeh, P. (2013) · eScholarship (California Digital Library)
RIPS: Rotor/Impeller Power System
Izenberg, N. R., Papadakis, S. J., Kott, T. M., Chatterjee, A., Adams, D., Perez, R. M., & Neville, J. (2023) · IEEE Aerospace Conference (AERO) · doi:10.1109/aero55745.2023.10115647
Sayanagi, K. M., Garland, J., & Saunders, W. (2025) · Elsevier eBooks · doi:10.1016/b978-0-323-96026-7.00224-1
Self-citationThe Dynamics of the Atmosphere of Saturn
Sánchez-Lavega, A. (2026) · doi:10.1093/9780197851500.003.0342
- Authors
- Sayanagi, K. M., Morales-Juberías, R., & Ingersoll, A. P.
- Affiliations
- California Institute of Technology (US)
- New Mexico Institute of Mining and Technology (US)
- Venue
- Journal of the Atmospheric Sciences
- Publisher
- American Meteorological Society
- Published
- 2010-08-01
- Volume
- 67
- Issue
- 8
- Pages
- 2658-2678
- ISSN
- 0022-4928 (ISSN-L)
- 1520-0469
- OpenAlex
- W2038496891
- Cited by
- 19
- References
- 56
- Citations by year
- 2026: 1 · 2025: 1 · 2023: 1 · 2022: 2 · 2021: 2 · 2020: 1 · 2019: 2 · 2018: 3 · 2015: 1 · 2013: 2 · 2012: 2
- FWCI
- 0.89
- Type
- journal article
- Language
- en
- Open access
- hybrid
- doi.org
- Licence
- public-domain
- Locations
- Journal of the Atmospheric Sciences (publishedVersion, public-domain)
- CaltechAUTHORS (California Institute of Technology) (submittedVersion)
- Topics
- Physical Sciences › Physics and Astronomy › Astronomy and Astrophysics › Astro and Planetary Science
- Physical Sciences › Engineering › Computational Mechanics › Fluid Dynamics and Turbulent Flows
- Physical Sciences › Physics and Astronomy › Astronomy and Astrophysics › Ionosphere and magnetosphere dynamics
- Keywords
- jet meandering, shear instability, potential vorticity gradient, western boundary currents, string of pearls
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