• Arnold, N. P., E. Tziperman, and B. Farrell, 2012: Abrupt transition to strong superrotation driven by equatorial wave resonance in an idealized GCM. J. Atmos. Sci., 69, 626640, https://doi.org/10.1175/JAS-D-11-0136.1.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Caballero, R., and M. Huber, 2010: Spontaneous transition to superrotation in warm climates simulated by CAM3. Geophys. Res. Lett., 37, L11701, https://doi.org/10.1029/2010GL043468.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Dias Pinto, J. R., and J. L. Mitchell, 2014: Atmospheric superrotation in an idealized GCM: Parameter dependence of the eddy response. Icarus, 238, 93109, https://doi.org/10.1016/j.icarus.2014.04.036.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Frierson, D. M., I. M. Held, and P. Zurita-Gotor, 2006: A gray-radiation aquaplanet moist GCM. Part I: Static stability and eddy scale. J. Atmos. Sci., 63, 25482566, https://doi.org/10.1175/JAS3753.1.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Gierasch, P. J., 1975: Meridional circulation and the maintenance of the Venus atmospheric rotation. J. Atmos. Sci., 32, 10381044, https://doi.org/10.1175/1520-0469(1975)032<1038:MCATMO>2.0.CO;2.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Held, I. M., and M. J. Suarez, 1994: A proposal for the intercomparison of the dynamical cores of atmospheric general circulation models. Bull. Amer. Meteor. Soc., 75, 18251830, https://doi.org/10.1175/1520-0477(1994)075<1825:APFTIO>2.0.CO;2.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Herbert, C., R. Caballero, and F. Bouchet, 2020: Atmospheric bistability and abrupt transitions to superrotation: Wave–jet resonance and Hadley cell feedbacks. J. Atmos. Sci., 77, 3149, https://doi.org/10.1175/JAS-D-19-0089.1.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Hide, R., 1969: Dynamics of the atmospheres of the major planets with an appendix on the viscous boundary layer at the rigid bounding surface of an electrically-conducting rotating fluid in the presence of a magnetic field. J. Atmos. Sci., 26, 841853, https://doi.org/10.1175/1520-0469(1969)026<0841:DOTAOT>2.0.CO;2.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Iga, S.-I., and Y. Matsuda, 2005: Shear instability in a shallow water model with implications for the Venus atmosphere. J. Atmos. Sci., 62, 25142527, https://doi.org/10.1175/JAS3484.1.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Laraia, A. L., and T. Schneider, 2015: Superrotation in terrestrial atmospheres. J. Atmos. Sci., 72, 42814296, https://doi.org/10.1175/JAS-D-15-0030.1.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Mendonça, J. M., and P. L. Read, 2016: Exploring the Venus global super-rotation using a comprehensive general circulation model. Planet. Space Sci., 134, 118, https://doi.org/10.1016/j.pss.2016.09.001.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Merlis, T. M., and T. Schneider, 2010: Atmospheric dynamics of Earth-like tidally locked aqua-planets. J. Adv. Model. Earth Syst., 2 (4), https://doi.org/10.3894/JAMES.2010.2.13.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Mitchell, J. L., and G. K. Vallis, 2010: The transition to superrotation in terrestrial atmospheres. J. Geophys. Res., 115, E12008, https://doi.org/10.1029/2010JE003587.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Polichtchouk, I., and J. Cho, 2016: Equatorial superrotation in Held and Suarez like flows with weak equator-to-pole surface temperature gradient. Quart. J. Roy. Meteor. Soc., 142, 15281540, https://doi.org/10.1002/qj.2755.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Potter, S. F., G. K. Vallis, and J. L. Michell, 2014: Spontaneous superrotation and the role of Kelvin waves in an idealized dry GCM. J. Atmos. Sci., 71, 596614, https://doi.org/10.1175/JAS-D-13-0150.1.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Read, P. L., and S. Lebonnois, 2018: Superrotation on Venus, on Titan, and elsewhere. Annu. Rev. Earth Planet. Sci., 46, 175202, https://doi.org/10.1146/annurev-earth-082517-010137.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Saravanan, R., 1993: Equatorial superrotation and maintenance of the general circulation in two-level models. J. Atmos. Sci., 50, 12111227, https://doi.org/10.1175/1520-0469(1993)050<1211:ESAMOT>2.0.CO;2.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Schneider, T., and J. Liu, 2009: Formation of jets and equatorial superrotation on Jupiter. J. Atmos. Sci., 66, 579601, https://doi.org/10.1175/2008JAS2798.1.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Shell, K. M., and I. M. Held, 2004: Abrupt transition to strong superrotation in an axisymmetric model of the upper troposphere. J. Atmos. Sci., 61, 29282935, https://doi.org/10.1175/JAS-3312.1.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Showman, A. P., and L. M. Polvani, 2011: Equatorial superrotation on tidally locked exoplanets. Astrophys. J., 738, 71, https://doi.org/10.1088/0004-637X/738/1/71.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Suarez, M. J., and D. G. Duffy, 1992: Terrestrial superrotation: A bifurcation of the general circulation. J. Atmos. Sci., 49, 15411554, https://doi.org/10.1175/1520-0469(1992)049<1541:TSABOT>2.0.CO;2.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Takagi, M., and Y. Matsuda, 2007: Effects of thermal tides on the Venus atmospheric superrotation. J. Geophys. Res., 112, D09112, https://doi.org/10.1029/2006JD007901.

    • Search Google Scholar
    • Export Citation
  • Vallis, G. K., and Coauthors, 2018: Isca, v1.0: A framework for the global modelling of the atmospheres of Earth and other planets at varying levels of complexity. Geosci. Model Dev., 11, 843859, https://doi.org/10.5194/gmd-11-843-2018.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Wang, P., and J. L. Mitchell, 2014: Planetary ageostrophic instability leads to superrotation. Geophys. Res. Lett., 41, 41184126, https://doi.org/10.1002/2014GL060345.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Williams, G., 2003: Barotropic instability and equatorial superrotation. J. Atmos. Sci., 60, 21362152, https://doi.org/10.1175/1520-0469(2003)060<2136:BIAES>2.0.CO;2.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Zurita-Gotor, P., 2008: The sensitivity of the isentropic slope in a primitive equation dry model. J. Atmos. Sci., 65, 4365, https://doi.org/10.1175/2007JAS2284.1.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Zurita-Gotor, P., 2019: The role of the divergent circulation for large-scale eddy momentum transport in the tropics. Part I: Observations. J. Atmos. Sci., 76 11251144, https://doi.org/10.1175/JAS-D-18-0297.1.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Zurita-Gotor, P., and I. M. Held, 2018: The finite amplitude evolution of mixed Kelvin–Rossby wave instability and equatorial superrotation in a shallow water model and an idealized GCM. J. Atmos. Sci., 75, 22992316, https://doi.org/10.1175/JAS-D-17-0386.1.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Zurita-Gotor, P., and I. M. Held, 2021: Westward-propagating Rossby modes in idealized GCMs. J. Atmos. Sci., 78, 15031522, https://doi.org/10.1175/JAS-D-20-0276.1.

    • Crossref
    • Search Google Scholar
    • Export Citation
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The Sensitivity of Superrotation to the Latitude of Baroclinic Forcing in a Terrestrial Dry Dynamical Core

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  • 1 aUniversidad Complutense de Madrid, Madrid, Spain
  • | 2 bInstituto de Geociencia UCM-CSIC, Madrid, Spain
  • | 3 cPrinceton University, Princeton, New Jersey
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Abstract

Previous studies have shown that Kelvin–Rossby instability is a viable mechanism for producing equatorial superrotation in small and/or slowly rotating planets. It is shown in this paper that this mechanism can also produce superrotation with terrestrial parameters when the baroclinic forcing moves to low latitudes, explaining previous results by Williams. The transition between superrotating and subrotating flow occurs abruptly as the baroclinic forcing moves poleward. Although Kelvin–Rossby instability weakens when the baroclinic zone moves away from the equator, the key factor explaining the abrupt transition is the change in the baroclinic eddies. When differential heating is contained within the tropics, baroclinic eddies do not decelerate the subtropical jet and the upper-tropospheric flow approximately conserves angular momentum, providing conditions favorable for Kelvin–Rossby instability. In contrast, when baroclinic eddies are generated in the extratropics, they decelerate the subtropical jet and prevent the Kelvin–Rossby coupling. Due to this sensitivity to baroclinic eddies, the system exhibits hysteresis: near the transition parameter, extratropical eddies can prevent superrotation when they are initially present.

© 2022 American Meteorological Society. For information regarding reuse of this content and general copyright information, consult the AMS Copyright Policy (www.ametsoc.org/PUBSReuseLicenses).

Corresponding author: Pablo Zurita-Gotor, pzurita@alum.mit.edu

Abstract

Previous studies have shown that Kelvin–Rossby instability is a viable mechanism for producing equatorial superrotation in small and/or slowly rotating planets. It is shown in this paper that this mechanism can also produce superrotation with terrestrial parameters when the baroclinic forcing moves to low latitudes, explaining previous results by Williams. The transition between superrotating and subrotating flow occurs abruptly as the baroclinic forcing moves poleward. Although Kelvin–Rossby instability weakens when the baroclinic zone moves away from the equator, the key factor explaining the abrupt transition is the change in the baroclinic eddies. When differential heating is contained within the tropics, baroclinic eddies do not decelerate the subtropical jet and the upper-tropospheric flow approximately conserves angular momentum, providing conditions favorable for Kelvin–Rossby instability. In contrast, when baroclinic eddies are generated in the extratropics, they decelerate the subtropical jet and prevent the Kelvin–Rossby coupling. Due to this sensitivity to baroclinic eddies, the system exhibits hysteresis: near the transition parameter, extratropical eddies can prevent superrotation when they are initially present.

© 2022 American Meteorological Society. For information regarding reuse of this content and general copyright information, consult the AMS Copyright Policy (www.ametsoc.org/PUBSReuseLicenses).

Corresponding author: Pablo Zurita-Gotor, pzurita@alum.mit.edu
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