• Allen, D., , and N. Nakamura, 2001: A seasonal climatology of effective diffusivity in the stratosphere. J. Geophys. Res., 106 (D8), 79177935, doi:10.1029/2000JD900717.

    • Search Google Scholar
    • Export Citation
  • Andrews, D., , J. Holton, , and C. Leovy, 1987: Middle Atmosphere Dynamics. Academic Press, 489 pp.

  • Birner, T., , and H. Bönisch, 2011: Residual circulation trajectories and transit times into the extratropical lowermost stratosphere. Atmos. Chem. Phys., 11, 817827, doi:10.5194/acp-11-817-2011.

    • Search Google Scholar
    • Export Citation
  • Bönisch, H., , A. Engel, , T. Birner, , P. Hoor, , D. W. Tarasick, , and E. A. Ray, 2011: On the structural changes in the Brewer–Dobson circulation after 2000. Atmos. Chem. Phys., 11, 39373948, doi:10.5194/acp-11-3937-2011.

    • Search Google Scholar
    • Export Citation
  • Brewer, A. W., 1949: Evidence for a world circulation provided by the measurements of helium and water vapor distribution in the stratosphere. Quart. J. Roy. Meteor. Soc., 75, 351363, doi:10.1002/qj.49707532603.

    • Search Google Scholar
    • Export Citation
  • Butchart, N., and Coauthors, 2010: Chemistry–climate model simulations of twenty-first century stratospheric climate and circulation changes. J. Climate, 23, 53495374, doi:10.1175/2010JCLI3404.1.

    • Search Google Scholar
    • Export Citation
  • Calvo, N., , R. R. Garcia, , W. J. Randel, , and D. R. Marsh, 2010: Dynamical mechanism for the increase in tropical upwelling in the lowermost tropical stratosphere during warm ENSO events. J. Atmos. Sci., 67, 23312340, doi:10.1175/2010JAS3433.1.

    • Search Google Scholar
    • Export Citation
  • Chen, G., , J. Lu, , and D. M. W. Frierson, 2008: Phase speed spectra and the latitude of surface westerlies: Interannual variability and global warming trend. J. Climate, 21, 59425959, doi:10.1175/2008JCLI2306.1.

    • Search Google Scholar
    • Export Citation
  • Chen, G., , R. A. Plumb, , and J. Lu, 2010: Sensitivities of zonal mean atmospheric circulation to SST warming in an aqua-planet model. Geophys. Res. Lett.,37, L12701, doi:10.1029/2010GL043473.

  • Deckert, R., , and M. Dameris, 2008: Higher tropical SSTs strengthen the tropical upwelling via deep convection. Geophys. Res. Lett.,35, L10813, doi:10.1029/2008GL033719.

  • Delworth, T. L., and Coauthors, 2006: GFDL’s CM2 global coupled climate models. Part I: Formulation and simulation characteristics. J. Climate, 19, 643674, doi:10.1175/JCLI3629.1.

    • Search Google Scholar
    • Export Citation
  • Dobson, G. M. B., 1956: Origin and distribution of the polyatomic molecules in the atmosphere. Proc. Roy. Soc. London, 236A, 187193, doi:10.1098/rspa.1956.0127.

    • Search Google Scholar
    • Export Citation
  • Donner, L. J., and Coauthors, 2011: The dynamical core, physical parameterizations, and basic simulation characteristics of the atmospheric component AM3 of the GFDL global coupled model CM3. J. Climate, 24, 34843519, doi:10.1175/2011JCLI3955.1.

    • Search Google Scholar
    • Export Citation
  • Edmon, H. J., Jr., , B. J. Hoskins, , and M. E. McIntyre, 1980: Eliassen–Palm cross sections for the troposphere. J. Atmos. Sci., 37, 26002616, doi:10.1175/1520-0469(1980)037<2600:EPCSFT>2.0.CO;2.

    • Search Google Scholar
    • Export Citation
  • Eichelberger, S. J., , and D. L. Hartmann, 2005: Changes in the strength of the Brewer–Dobson circulation in a simple AGCM. Geophys. Res. Lett.,32, L15807, doi:10.1029/2005GL022924.

  • Engel, A., and Coauthors, 2008: Age of stratospheric air unchanged within uncertainties over the past 30 years. Nat. Geosci., 2, 2831, doi:10.1038/ngeo388.

    • Search Google Scholar
    • Export Citation
  • Garcia, R. R., , and W. J. Randel, 2008: Acceleration of the Brewer–Dobson circulation due to increases in greenhouse gases. J. Atmos. Sci., 65, 27312739, doi:10.1175/2008JAS2712.1.

    • Search Google Scholar
    • Export Citation
  • Garcia, R. R., , W. J. Randel, , and D. E. Kinnison, 2011: On the determination of age of air trends from atmospheric trace species. J. Atmos. Sci., 68, 139154, doi:10.1175/2010JAS3527.1.

    • Search Google Scholar
    • Export Citation
  • García-Herrera, R., , N. Calvo, , R. R. Garcia, , and M. A. Giorgetta, 2006: Propagation of ENSO temperature signals into the middle atmosphere: A comparison of two general circulation models and ERA-40 reanalysis data. J. Geophys. Res., 111, D06101, doi:10.1029/2005JD006061.

    • Search Google Scholar
    • Export Citation
  • Garny, H., , M. Dameris, , W. J. Randel, , G. E. Bodeker, , and R. Deckert, 2011: Dynamically forced increase of tropical upwelling in the lower stratosphere. J. Atmos. Sci., 68, 12141233, doi:10.1175/2011JAS3701.1.

    • Search Google Scholar
    • Export Citation
  • Gerber, E. P., 2012: Stratospheric versus tropospheric control of the strength and structure of the Brewer–Dobson circulation. J. Atmos. Sci., 69, 28572877, doi:10.1175/JAS-D-11-0341.1.

    • Search Google Scholar
    • Export Citation
  • Hall, T. M., , and R. A. Plumb, 1994: Age as a diagnostic of stratospheric transport. J. Geophys. Res., 99 (D1), 10591070, doi:10.1029/93JD03192.

    • Search Google Scholar
    • Export Citation
  • Hardiman, S. C., , N. Butchart, , P. H. Haynes, , and S. H. E. Hare, 2007: A note on forced versus internal variability of the stratosphere. Geophys. Res. Lett.,34, L12803, doi:10.1029/2007GL029726.

  • Harnik, N., , and R. S. Lindzen, 2001: The effect of reflecting surfaces on the vertical structure and variability of stratospheric planetary waves. J. Atmos. Sci., 58, 28722894, doi:10.1175/1520-0469(2001)058<2872:TEORSO>2.0.CO;2.

    • Search Google Scholar
    • Export Citation
  • Haynes, P., , and E. Shuckburgh, 2000a: Effective diffusivity as a diagnostic of atmospheric transport: 1. Stratosphere. J. Geophys. Res., 105 (D18), 22 77722 794, doi:10.1029/2000JD900093.

    • Search Google Scholar
    • Export Citation
  • Haynes, P., , and E. Shuckburgh, 2000b: Effective diffusivity as a diagnostic of atmospheric transport: 2. Troposphere and lower stratosphere. J. Geophys. Res., 105 (D18), 22 79522 810, doi:10.1029/2000JD900092.

    • Search Google Scholar
    • Export Citation
  • Haynes, P., , C. J. Marks, , M. E. Mcintyre, , T. G. Shepherd, , and K. P. Shine, 1991: On the “downward control” of extratropical diabatic circulation by eddy-induced mean zonal forces. J. Atmos. Sci., 48, 651678, doi:10.1175/1520-0469(1991)048<0651:OTCOED>2.0.CO;2.

    • Search Google Scholar
    • Export Citation
  • Haynes, P., , D. A. Poet, , and E. F. Shuckburgh, 2007: Transport and mixing in kinematic and dynamically consistent flows. J. Atmos. Sci., 64, 36403651, doi:10.1175/JAS4030.1.

    • Search Google Scholar
    • Export Citation
  • Hegglin, M. I., , and T. G. Shepherd, 2009: Large climate-induced changes in ultraviolet index and stratosphere-to-troposphere ozone flux. Nat. Geosci., 2, 687691, doi:10.1038/ngeo604.

    • Search Google Scholar
    • Export Citation
  • Holton, J. R., 1986: Meridional distribution of stratospheric trace constituents. J. Atmos. Sci., 43, 12381242, doi:10.1175/1520-0469(1986)043<1238:MDOSTC>2.0.CO;2.

    • 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, doi:10.1029/95RG02097.

    • Search Google Scholar
    • Export Citation
  • Kerr-Munslow, A. M., , and W. A. Norton, 2006: Tropical wave driving of the annual cycle in tropical tropopause temperatures. Part I: ECMWF analyses. J. Atmos. Sci., 63, 14101419, doi:10.1175/JAS3697.1.

    • Search Google Scholar
    • Export Citation
  • Li, F., , J. Austin, , and J. Wilson, 2008: The strength of the Brewer–Dobson circulation in a changing climate: Coupled chemistry–climate model simulations. J. Climate, 21, 4057, doi:10.1175/2007JCLI1663.1.

    • Search Google Scholar
    • Export Citation
  • Liu, J., , and T. Schneider, 2011: Convective generation of equatorial superrotation in planetary atmospheres. J. Atmos. Sci., 68, 27422756, doi:10.1175/JAS-D-10-05013.1.

    • Search Google Scholar
    • Export Citation
  • Lu, J., , G. Chen, , and D. M. W. Frierson, 2008: Response of the zonal mean atmospheric circulation to El Niño versus global warming. J. Climate, 21, 58355851, doi:10.1175/2008JCLI2200.1.

    • Search Google Scholar
    • Export Citation
  • Mahlman, J. D., , H. I. Levy, , and W. J. Moxim, 1986: Three-dimensional simulations of stratospheric N2O: Predictions for other. J. Geophys. Res., 91, 26872707, doi:10.1029/JD091iD02p02687.

    • Search Google Scholar
    • Export Citation
  • Matsuno, T., 1970: Vertical propagation of stationary planetary waves in the winter Northern Hemisphere. J. Atmos. Sci., 27, 871883, doi:10.1175/1520-0469(1970)027<0871:VPOSPW>2.0.CO;2.

    • Search Google Scholar
    • Export Citation
  • McLandress, C., , and T. G. Shepherd, 2009: Simulated anthropogenic changes in the Brewer–Dobson circulation, including its extension to high latitudes. J. Climate, 22, 15161540, doi:10.1175/2008JCLI2679.1.

    • Search Google Scholar
    • Export Citation
  • Nakamura, N., 1996: Two-dimensional mixing, edge formation, and permeability diagnosed in an area coordinate. J. Atmos. Sci., 53, 1524–1537, doi:10.1175/1520-0469(1996)053<1524:TDMEFA>2.0.CO;2.

    • Search Google Scholar
    • Export Citation
  • Neale, R. B., , and B. J. Hoskins, 2000: A standard test for AGCMs including their physical parametrizations: I: The proposal. Atmos. Sci. Lett., 1, 101107, doi:10.1006/asle.2000.0022.

    • Search Google Scholar
    • Export Citation
  • Norton, W. A., 2006: Tropical wave driving of the annual cycle in tropical tropopause temperatures. Part II: Model results. J. Atmos. Sci., 63, 14201431, doi:10.1175/JAS3698.1.

    • Search Google Scholar
    • Export Citation
  • Olsen, M. A., , M. R. Schoeberl, , and J. E. Nielsen, 2007: Response of stratospheric circulation and stratosphere–troposphere exchange to changing sea surface temperatures. J. Geophys. Res.,112, D16104, doi:10.1029/2006JD008012.

  • Plumb, R. A., 2002: Stratospheric transport. J. Meteor. Soc. Japan,80, 793809.

  • Polvani, L., , and P. Kushner, 2002: Tropospheric response to stratospheric perturbations in a relatively simple general circulation model. Geophys. Res. Lett., 29, 4043, doi:10.1029/2001GL014284.

    • Search Google Scholar
    • Export Citation
  • Randel, W. J., , R. R. Garcia, , and F. Wu, 2008: Dynamical balances and tropical stratospheric upwelling. J. Atmos. Sci., 65, 35843595, doi:10.1175/2008JAS2756.1.

    • Search Google Scholar
    • Export Citation
  • Randel, W. J., , R. R. Garcia, , N. Calvo, , and D. Marsh, 2009: ENSO influence on zonal mean temperature and ozone in the tropical lower stratosphere. Geophys. Res. Lett.,36, L15822, doi:10.1029/2009GL039343.

  • Ray, E. A., and Coauthors, 2010: Evidence for changes in stratospheric transport and mixing over the past three decades based on multiple data sets and tropical leaky pipe analysis. J. Geophys. Res.,115, D21304, doi:10.1029/2010JD014206.

  • Rind, D., , D. Shindell, , P. Lonergan, , and N. K. Balachandran, 1998: Climate change and the middle atmosphere. Part III: The doubled CO2 climate revisited. J. Climate, 11, 876894, doi:10.1175/1520-0442(1998)011<0876:CCATMA>2.0.CO;2.

    • Search Google Scholar
    • Export Citation
  • Ryu, J.-H., , and S. Lee, 2010: Effect of tropical waves on the tropical tropopause transition layer upwelling. J. Atmos. Sci., 67, 31303148, doi:10.1175/2010JAS3434.1.

    • Search Google Scholar
    • Export Citation
  • Scinocca, J., , and P. Haynes, 1998: Dynamical forcing of stratospheric planetary waves by tropospheric baroclinic eddies. J. Atmos. Sci., 55, 23612392, doi:10.1175/1520-0469(1998)055<2361:DFOSPW>2.0.CO;2.

    • Search Google Scholar
    • Export Citation
  • Scott, R. K., , and J. Cammas, 2002: Wave breaking and mixing at the subtropical tropopause. J. Atmos. Sci., 59, 23472361, doi:10.1175/1520-0469(2002)059<2347:WBAMAT>2.0.CO;2.

    • Search Google Scholar
    • Export Citation
  • Scott, R. K., , E. F. Shuckburgh, , J. P. Cammas, , and B. Legras, 2003: Stretching rates and equivalent length near the tropopause. J. Geophys. Res., 108, 4394, doi:10.1029/2002JD002988.

    • Search Google Scholar
    • Export Citation
  • Shepherd, T. G., , and C. McLandress, 2011: A robust mechanism for strengthening of the Brewer–Dobson circulation in response to climate change: Critical-layer control of subtropical wave breaking. J. Atmos. Sci., 68, 784797, doi:10.1175/2010JAS3608.1.

    • Search Google Scholar
    • Export Citation
  • Shuckburgh, E., , F. D. Ovidio, , and B. Legras, 2009: Local mixing events in the upper troposphere and lower stratosphere. Part II: Seasonal and interannual variability. J. Atmos. Sci., 66, 36953706, doi:10.1175/2009JAS2983.1.

    • Search Google Scholar
    • Export Citation
  • Simpson, I. R., , T. G. Shepherd, , and M. Sigmond, 2011: Dynamics of the lower stratospheric circulation response to ENSO. J. Atmos. Sci., 68, 25372556, doi:10.1175/JAS-D-11-05.1.

    • Search Google Scholar
    • Export Citation
  • Thompson, D. W. J., , and S. Solomon, 2005: Recent stratospheric climate trends as evidenced in radiosonde data: Global structure and tropospheric linkages. J. Climate, 18, 47854795, doi:10.1175/JCLI3585.1.

    • Search Google Scholar
    • Export Citation
  • Waugh, D., 2009: Atmospheric dynamics: The age of stratospheric air. Nat. Geosci., 2, 1416, doi:10.1038/ngeo397.

  • Waugh, D., , and T. Hall, 2002: Age of stratospheric air: Theory, observations, and models. Rev. Geophys., 40, 1010, doi:10.1029/2000RG000101.

    • Search Google Scholar
    • Export Citation
  • Yang, H., , K. Tung, , and E. Olaguer, 1990: Nongeostrophic theory of zonally averaged circulation. Part II: Eliassen–Palm flux divergence and isentropic mixing coefficient. J. Atmos. Sci., 47, 215241, doi:10.1175/1520-0469(1990)047<0215:NTOZAC>2.0.CO;2.

    • Search Google Scholar
    • Export Citation
All Time Past Year Past 30 Days
Abstract Views 0 0 0
Full Text Views 18 18 2
PDF Downloads 16 16 2

Sensitivities of the Lower-Stratospheric Transport and Mixing to Tropical SST Heating

View More View Less
  • 1 Department of Earth and Atmospheric Sciences, Cornell University, Ithaca, New York
  • 2 Institute of Oceanography, University of Hamburg, Hamburg, Germany
© Get Permissions
Restricted access

Abstract

The sensitivities of the Brewer–Dobson circulation (BDC) to different distributions of tropical SST heating are investigated in an idealized aquaplanet model. It is found that an increase in tropical SSTs generally leads to an acceleration of tropical upwelling and an associated reduction in the age of air (AOA) in the polar stratosphere and that the AOA near the subtropical tropopause is correlated with local isentropic mixing of tropospheric air with stratospheric air.

The zonal distribution of SST perturbations has a major impact on the vertical and meridional structure of the BDC as compared with other SST characteristics. Zonally localized SST heatings tend to generate a shallow acceleration of the stratospheric residual circulation, enhanced isentropic mixing associated with a weakened stratospheric jet, and a reduction in AOA mostly within the polar vortex. In contrast, SST heatings with a zonally symmetric structure tend to produce a deep strengthening of the stratospheric residual circulation, suppressed isentropic mixing associated with a stronger stratospheric jet, and a decrease of AOA in the entire stratosphere. The shallow versus deep strengthening of the stratospheric residual circulation change has been linked to wave propagation and dissipation in the subtropical lower stratosphere rather than wave generation in the troposphere, and the former can be strongly affected by the vertical position of the subtropical jet. These results suggest that, while the longitudinally localized SST trends under climate change may contribute to the change in the shallow branch of the BDC, the upward shift of the subtropical jet associated with the zonal SST heating can impact the deep branch of the BDC.

Corresponding author address: Huang Yang, 1126 Bradfield Hall, Department of Earth and Atmospheric Sciences, Cornell University, Ithaca, NY 14853. E-mail: hy337@cornell.edu

Abstract

The sensitivities of the Brewer–Dobson circulation (BDC) to different distributions of tropical SST heating are investigated in an idealized aquaplanet model. It is found that an increase in tropical SSTs generally leads to an acceleration of tropical upwelling and an associated reduction in the age of air (AOA) in the polar stratosphere and that the AOA near the subtropical tropopause is correlated with local isentropic mixing of tropospheric air with stratospheric air.

The zonal distribution of SST perturbations has a major impact on the vertical and meridional structure of the BDC as compared with other SST characteristics. Zonally localized SST heatings tend to generate a shallow acceleration of the stratospheric residual circulation, enhanced isentropic mixing associated with a weakened stratospheric jet, and a reduction in AOA mostly within the polar vortex. In contrast, SST heatings with a zonally symmetric structure tend to produce a deep strengthening of the stratospheric residual circulation, suppressed isentropic mixing associated with a stronger stratospheric jet, and a decrease of AOA in the entire stratosphere. The shallow versus deep strengthening of the stratospheric residual circulation change has been linked to wave propagation and dissipation in the subtropical lower stratosphere rather than wave generation in the troposphere, and the former can be strongly affected by the vertical position of the subtropical jet. These results suggest that, while the longitudinally localized SST trends under climate change may contribute to the change in the shallow branch of the BDC, the upward shift of the subtropical jet associated with the zonal SST heating can impact the deep branch of the BDC.

Corresponding author address: Huang Yang, 1126 Bradfield Hall, Department of Earth and Atmospheric Sciences, Cornell University, Ithaca, NY 14853. E-mail: hy337@cornell.edu
Save