• Allen, S. J., , and R. A. Vincent, 1995: Gravity wave activity in the lower atmosphere: Seasonal and latitudinal variations. J. Geophys. Res., 100 , 13271350.

    • Search Google Scholar
    • Export Citation
  • Andrews, D. G., , and M. E. McIntyre, 1976: Planetary waves in horizontal and vertical shear: The generalized Eliassen–Palm relation and mean-zonal acceleration. J. Atmos. Sci., 33 , 20312048.

    • Search Google Scholar
    • Export Citation
  • Bartels, J., , D. Peters, , and G. Schmitz, 1998: Climatological Ertel’s potential-vorticity flux and mean meridional circulation in the extratropical troposphere–lower stratosphere. Ann. Geophys., 16 , 250265.

    • Search Google Scholar
    • Export Citation
  • Berthet, G., , J. G. Esler, , and P. H. Haynes, 2007: A Lagrangian perspective of the tropopause and the ventilation of the lowermost stratosphere. J. Geophys. Res., 112 , D18102. doi:10.1029/2006JD008295.

    • Search Google Scholar
    • Export Citation
  • Birner, T., 2006: Fine-scale structure of the extratropical tropopause region. J. Geophys. Res., 111 , D04104. doi:10.1029/2005JD006301.

  • Birner, T., , A. Dornbrack, , and U. Schumann, 2002: How sharp is the tropopause at midlatitudes? Geophys. Res. Lett., 29 , 1700. doi:10.1029/2002GL015142.

    • Search Google Scholar
    • Export Citation
  • Bratseth, A. M., 1998: On the estimation of transport characteristics of atmospheric data sets. Tellus, 50A , 451467.

  • Brioude, J., , J-P. Cammas, , O. R. Cooper, , and P. Nedelec, 2008: Characterization of the composition, structure, and seasonal variation of the mixing layer above the extratropical tropopause as revealed by MOZAIC measurements. J. Geophys. Res., 113 , D00B01. doi:10.1029/2007JD009184.

    • Search Google Scholar
    • Export Citation
  • Chen, P., , J. R. Holton, , A. O’Neill, , and R. Swinbank, 1994: Isentropic mass exchange between the tropics and extratropics in the stratosphere. J. Atmos. Sci., 51 , 30063018.

    • Search Google Scholar
    • Export Citation
  • Clark, T. L., , and W. R. Peltier, 1977: On the evolution and stability of finite-amplitude mountain waves. J. Atmos. Sci., 34 , 17151730.

    • Search Google Scholar
    • Export Citation
  • Duck, T., , and J. A. Whiteway, 2005: The spectrum of waves and turbulence at the tropopause. Geophys. Res. Lett., 32 , L07801. doi:10.1029/2004GL021189.

    • Search Google Scholar
    • Export Citation
  • Dunkerton, T. J., 1989: Theory of internal gravity wave saturation. Pure Appl. Geophys., 130 , 373397.

  • Fischer, H., and Coauthors, 2000: Tracer correlations in the northern high latitude lowermost stratosphere: Influence of cross-tropopause mass exchange. Geophys. Res. Lett., 27 , 97100.

    • Search Google Scholar
    • Export Citation
  • Fritts, D. C., , and M. J. Alexander, 2003: Gravity wave dynamics and effects in the middle atmosphere. Rev. Geophys., 41 , 1003. doi:10.1029/2001RG000106.

    • Search Google Scholar
    • Export Citation
  • Haynes, P. H., , and E. F. Schuckburgh, 2000: Effective diffusivity as a diagnostic of atmospheric transport. 2. Troposphere and lower stratosphere. J. Geophys. Res., 105 , 2279522810.

    • Search Google Scholar
    • Export Citation
  • Haynes, P. H., , C. J. Marks, , M. E. McIntyre, , T. G. Shepherd, , and K. P. Shine, 1991: On the “downward control” of extratropical diabatic circulations by eddy-induced mean zonal forces. J. Atmos. Sci., 48 , 651678.

    • Search Google Scholar
    • Export Citation
  • Hegglin, M. I., , D. Brunner, , T. Peter, , J. Staehelin, , V. Wirth, , P. Hoor, , and H. Fischer, 2005: Determination of eddy diffusivity in the lowermost stratosphere. Geophys. Res. Lett., 32 , L13812. doi:10.1029/2005GL022495.

    • Search Google Scholar
    • Export Citation
  • Hegglin, M. I., , C. D. Boone, , G. L. Manney, , and K. A. Walker, 2009: A global view of the extratropical tropopause transition layer from Atmospheric Chemistry Experiment Fourier Transform Spectrometer O3, H2O, and CO. J. Geophys. Res., 114 , D00B11. doi:10.1029/2008JD009984.

    • Search Google Scholar
    • Export Citation
  • Hitchman, M. H., , and A. S. Huesmann, 2007: A seasonal climatology of Rossby wave breaking in the 330–2000-K layer. J. Atmos. Sci., 39 , 19221940.

    • Search Google Scholar
    • Export Citation
  • Holton, J. R., , P. H. Haynes, , M. E. McIntyre, , A. R. Douglass, , R. B. Rood, , and L. Pfister, 1995: Stratosphere–troposphere exchange. Rev. Geophys., 33 , 403439.

    • Search Google Scholar
    • Export Citation
  • Hoor, P., , C. Gurk, , D. Brunner, , M. I. Hegglin, , H. Wernli, , and H. Fischer, 2004: Seasonality and extent of extratropical TST derived from in-situ CO measurements during SPURT. Atmos. Chem. Phys., 4 , 14271442.

    • Search Google Scholar
    • Export Citation
  • Lamarque, J-F., , A. Langford, , and M. Proffitt, 1996: Cross-tropopause mixing of ozone through gravity wave breaking: Observation and modeling. J. Geophys. Res., 101 , 2296922976.

    • Search Google Scholar
    • Export Citation
  • Lane, T. P., , and R. D. Sharman, 2008: Some influences of background flow conditions on the generation of turbulence due to gravity wave breaking above deep convection. J. Appl. Meteor. Climatol., 47 , 27772796.

    • Search Google Scholar
    • Export Citation
  • Lane, T. P., , R. D. Sharman, , T. L. Clark, , and H-M. Hsu, 2003: An investigation of turbulence generation mechanisms above deep convection. J. Atmos. Sci., 60 , 12971321.

    • Search Google Scholar
    • Export Citation
  • Lindzen, R. S., 1981: Turbulence and stress owing to gravity wave and tidal breakdown. J. Geophys. Res., 86 , 97079714.

  • Lyjak, L. V., , and V. A. Yudin, 2005: Diagnostics of the large-scale mixing properties from stratospheric analyses. J. Geophys. Res., 110 , D17107. doi:10.1029/2004JD005577.

    • Search Google Scholar
    • Export Citation
  • McIntyre, M. E., , and T. N. Palmer, 1984: The ‘surf zone’ in the stratosphere. J. Atmos. Terr. Phys., 46 , 825849.

  • Miyazaki, K., , and T. Iwasaki, 2005: Diagnosis of meridional ozone transport based on mass-weighted isentropic zonal means. J. Atmos. Sci., 63 , 11921208.

    • Search Google Scholar
    • Export Citation
  • Miyazaki, K., , and T. Iwasaki, 2009: Isentropic diffusion coefficient derived from chemical constituent data. SOLA, 5 , 912. doi:10.2151/sola.2009-003.

    • Search Google Scholar
    • Export Citation
  • Miyazaki, K., , S. Watanabe, , Y. Kawatani, , Y. Tomikawa, , M. Takahashi, , and K. Sato, 2010: Transport and mixing in the extratropical tropopause region in a high-vertical-resolution GCM. Part I: Potential vorticity and heat budget analysis. J. Atmos. Sci., 67 , 12931314.

    • Search Google Scholar
    • Export Citation
  • Nakamura, N., 1996: Two-dimensional mixing, edge formation, and permeability diagnosed in area coordinates. J. Atmos. Sci., 53 , 15241537.

    • Search Google Scholar
    • Export Citation
  • Newman, P. A., , M. R. Schoeberl, , R. A. Plumb, , and J. E. Rosenfield, 1988: Mixing rates calculated from potential vorticity. J. Geophys. Res., 93 , 52215240.

    • Search Google Scholar
    • Export Citation
  • O’Sullivan, D. J., , and T. J. Dunkerton, 1995: Generation of inertia–gravity waves in a simulated life cycle of baroclinic instability. J. Atmos. Sci., 52 , 36953716.

    • Search Google Scholar
    • Export Citation
  • Pavelin, E., , J. Whiteway, , R. Busen, , and J. Hacker, 2002: Airborne observations of turbulence, mixing and gravity waves in the tropopause region. J. Geophys. Res., 107 , 4084. doi:10.1029/2001JD000775.

    • Search Google Scholar
    • Export Citation
  • Plougonven, R., , and C. Snyder, 2005: Gravity waves excited by jets: Propagation versus generation. Geophys. Res. Lett., 32 , L18802. doi:10.1029/2005GL023730.

    • Search Google Scholar
    • Export Citation
  • Plougonven, R., , and C. Snyder, 2007: Inertia–gravity waves spontaneously generated by jets and fronts. Part I: Different baroclinic life cycles. J. Atmos. Sci., 64 , 25022520.

    • Search Google Scholar
    • Export Citation
  • Postel, G. A., , and M. H. Hitchman, 1999: A climatology of Rossby wave breaking along the subtropical tropopause. J. Atmos. Sci., 56 , 359373.

    • Search Google Scholar
    • Export Citation
  • Postel, G. A., , and M. H. Hitchman, 2001: A case study of Rossby wave breaking along the subtropical tropopause. Mon. Wea. Rev., 129 , 25552569.

    • Search Google Scholar
    • Export Citation
  • Rosenlof, K. H., , and J. R. Holton, 1993: Estimates of the stratospheric residual circulation using the downward control principle. J. Geophys. Res., 98 , 1046510479.

    • Search Google Scholar
    • Export Citation
  • Sato, K., 1994: A statistical study of the structure, saturation and sources of inertio-gravity waves in the lower stratosphere observed with the MU radar. J. Atmos. Terr. Phys., 56 , 755774.

    • Search Google Scholar
    • Export Citation
  • Sato, K., , H. Eito, , and I. Hirota, 1993: Medium-scale traveling waves in the extratropical upper troposphere. J. Meteor. Soc. Japan, 71 , 427436.

    • Search Google Scholar
    • Export Citation
  • Sato, K., , D. J. O’Sullivan, , and T. J. Dunkerton, 1997: Low-frequency inertia–gravity waves in the stratosphere revealed by three-week continuous observation with the MU radar. Geophys. Res. Lett., 24 , 17391742.

    • Search Google Scholar
    • Export Citation
  • Sato, K., , S. Watanabe, , Y. Kawatani, , Y. Tomikawa, , K. Miyazaki, , and M. Takahashi, 2009: On the origins of mesospheric gravity waves. Geophys. Res. Lett., 36 , L19801. doi:10.1029/2009GL039908.

    • Search Google Scholar
    • Export Citation
  • Schmidt, T., , A. de la Torre, , and J. Wickert, 2008: Global gravity wave activity in the tropopause region from CHAMP radio occultation data. Geophys. Res. Lett., 35 , L16807. doi:10.1029/2008GL034986.

    • Search Google Scholar
    • Export Citation
  • Shapiro, M. A., 1980: Turbulent mixing within tropopause folds as a mechanism for the exchange of chemical constituents between the stratosphere and troposphere. J. Atmos. Sci., 37 , 9941004.

    • Search Google Scholar
    • Export Citation
  • Stone, E. M., , W. J. Randel, , and J. L. Stanford, 1999: Transport of passive tracers in baroclinic wave life cycles. J. Atmos. Sci., 56 , 13641381.

    • Search Google Scholar
    • Export Citation
  • Tomikawa, Y., , K. Sato, , S. Watanabe, , Y. Kawatani, , K. Miyazaki, , and M. Takahashi, 2008: Wintertime temperature maximum at the subtropical stratopause in a T213L256 GCM. J. Geophys. Res., 113 , D17117. doi:10.1029/2008JD009786.

    • Search Google Scholar
    • Export Citation
  • Tung, K. K., 1986: Nongeostrophic theory of zonally averaged circulation. Part I: Formulation. J. Atmos. Sci., 43 , 26002618.

  • VanZandt, T. E., , and D. C. Fritts, 1989: A theory of enhanced saturation of the gravity wave spectrum due to increases in atmospheric stability. Pure Appl. Geophys., 130 , 399420.

    • Search Google Scholar
    • Export Citation
  • Watanabe, S., , Y. Kawatani, , Y. Tomikawa, , K. Miyazaki, , M. Takahashi, , and K. Sato, 2008: General aspects of a T213L256 middle atmosphere general circulation model. J. Geophys. Res., 113 , D12110. doi:10.1029/2008JD010026.

    • Search Google Scholar
    • Export Citation
  • Watanabe, S., , K. Tomikawa, , Y. Sato, , Y. K. Kawatani, , M. Miyazaki, , and Takahashi, 2009: Simulation of the eastward 4-day wave in the Antarctic winter mesosphere using a gravity wave resolving general circulation model. J. Geophys. Res., 114 , D16111. doi:10.1029/2008JD011636.

    • Search Google Scholar
    • Export Citation
  • WMO, 1957: Definition of the tropopause. WMO Bull., 6 , 136.

  • Yamamori, M., , K. Sato, , and I. Hirota, 1997: A study on seasonal variation of upper tropospheric medium-scale waves over East Asia based on regional climate model data. J. Meteor. Soc. Japan, 75 , 1322.

    • Search Google Scholar
    • Export Citation
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Transport and Mixing in the Extratropical Tropopause Region in a High-Vertical-Resolution GCM. Part II: Relative Importance of Large-Scale and Small-Scale Dynamics

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  • 1 Research Institute for Global Change, Japan Agency for Marine-Earth Science and Technology, Yokohama, Japan
  • | 2 Department of Earth and Planetary Science, Graduate School of Science, University of Tokyo, Tokyo, Japan
  • | 3 National Institute of Polar Research, Tokyo, Japan
  • | 4 Center for Climate System Research, University of Tokyo, Kashiwa, Japan
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Abstract

The relative roles of atmospheric motions on various scales, from mesoscale to planetary scale, in transport and mixing in the extratropical tropopause region are investigated using a high-vertical-resolution general circulation model (GCM). The GCM with a vertical resolution of about 300 m explicitly represents the propagation and breaking of gravity waves and the induced transport and mixing. A downward control calculation shows that the Eliassen–Palm (E-P) flux of the gravity waves diverges and induces a mean equatorward flow in the extratropical tropopause region, which differs from the mean poleward flow induced by the convergence of large-scale E-P fluxes. The diffusion coefficients estimated from the eddy potential vorticity flux in tropopause-based coordinates reveal that isentropic motions diffuse air between 20 K below and 10 K above the tropopause from late autumn to early spring, while vertical mixing is strongly suppressed at around 10–15 K above the tropopause throughout the year. The isentropic mixing is mainly caused by planetary- and synoptic-scale motions, while small-scale motions with a horizontal scale of less than a few thousand kilometers largely affect the three-dimensional mixing just above the tropopause. Analysis of the gravity wave energy and atmospheric instability implies that the small-scale dynamics associated with the dissipation and saturation of gravity waves is a significant cause of the three-dimensional mixing just above the tropopause. A rapid increase in the static stability in the tropopause inversion layer is considered to play an important role in controlling the gravity wave activity around the tropopause.

Corresponding author address: Kazuyuki Miyazaki, Research Institute for Global Change, Japan Agency for Marine-Earth Science and Technology, 3173-25 Showa-machi, Kanazawa-ku, Yokohama, Japan 236-0001. Email: kmiyazaki@jamstec.go.jp

Abstract

The relative roles of atmospheric motions on various scales, from mesoscale to planetary scale, in transport and mixing in the extratropical tropopause region are investigated using a high-vertical-resolution general circulation model (GCM). The GCM with a vertical resolution of about 300 m explicitly represents the propagation and breaking of gravity waves and the induced transport and mixing. A downward control calculation shows that the Eliassen–Palm (E-P) flux of the gravity waves diverges and induces a mean equatorward flow in the extratropical tropopause region, which differs from the mean poleward flow induced by the convergence of large-scale E-P fluxes. The diffusion coefficients estimated from the eddy potential vorticity flux in tropopause-based coordinates reveal that isentropic motions diffuse air between 20 K below and 10 K above the tropopause from late autumn to early spring, while vertical mixing is strongly suppressed at around 10–15 K above the tropopause throughout the year. The isentropic mixing is mainly caused by planetary- and synoptic-scale motions, while small-scale motions with a horizontal scale of less than a few thousand kilometers largely affect the three-dimensional mixing just above the tropopause. Analysis of the gravity wave energy and atmospheric instability implies that the small-scale dynamics associated with the dissipation and saturation of gravity waves is a significant cause of the three-dimensional mixing just above the tropopause. A rapid increase in the static stability in the tropopause inversion layer is considered to play an important role in controlling the gravity wave activity around the tropopause.

Corresponding author address: Kazuyuki Miyazaki, Research Institute for Global Change, Japan Agency for Marine-Earth Science and Technology, 3173-25 Showa-machi, Kanazawa-ku, Yokohama, Japan 236-0001. Email: kmiyazaki@jamstec.go.jp

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