We thank John Thuburn, Roger Brugge, and Dave Knowles for developing the USMM;Paul Berrisford and Dingmin Li for supplying the ECMWF data; Gordon Watson and Anne Pardaens for technical assistance; and Hugh Pumphrey for providing maps of PV from the UKMO data. Karen Rosenlof supplied the code to calculate EP fluxes. John Thuburn, William Lahoz, Richard Swinbank, Donal O’Sullivan, and Alan O’Neill gave valuable suggestions; Gloria Manney provided a thorough and constructive review. This work was supported largely by the Natural Environment Research Council (United Kingdom) through UGAMP, and also by the National Aeronautics and Space Administration contracts NAS1-96071 and NAS5-32862. Publication costs were met by NorthWest Research Associates from its internal budget.
Andrews, D. G., J. R. Holton, and C. B. Leovy, 1987: Middle Atmosphere Dynamics. Academic Press, 489 pp.
Beck, A., 1996: The stability of the northern stratospheric winter polar vortex in dependence on the horizontal resolution in a global model. Beitr. Phys. Atmos.,69, 449–460.
Boville, B. A., 1995: Middle atmosphere version of CCM2 (MACCM2): Annual cycle and interannual variability. J. Geophys. Res.,100, 9017–9039.
Butchart, N., and E. E. Remsberg, 1986: The area of the stratospheric polar vortex as a diagnostic for tracer transport on an isentropic surface. J. Atmos. Sci.,43, 1319–1339.
——, S. A. Clough, T. N. Palmer, and P. J. Trevelyan, 1982: Simulations of an observed stratospheric warming with quasigeostrophic refractive index as a model diagnostic. Quart. J. Roy. Meteor. Soc.,108, 475–502.
Dunkerton, T. J., C. P. F. Hsu, and M. E. McIntyre, 1981: Some Eulerian and Lagrangian diagnostics for a model stratospheric warming. J. Atmos. Sci.,38, 819–843.
Edmon, H. J., B. J. Hoskins, and M. E. McIntyre, 1980: Eliassen–Palm cross sections for the troposphere. J. Atmos. Sci.,37, 2600–2616.
Erlebach, P., U. Langematz, and S. Pawson, 1996: Simulations of stratospheric sudden warming in the Berlin troposphere–stratosphere-mesosphere GCM. Ann. Geophys.,14, 443–465.
Farrara, J. D., M. Fisher, C. R. Mechoso, and A. O’Neill, 1992: Planetary-scale disturbances in the southern stratosphere during early winter. J. Atmos. Sci.,49, 1757–1775.
Fisher, M., A. O’Neill, and R. Sutton, 1993: Rapid descent of mesospheric air into the stratospheric polar vortex. Geophys. Res. Lett.,20, 1267–1270.
Harwood, R. S., 1975: The temperature structure of the southern hemisphere stratosphere August–October 1971. Quart. J. Roy. Meteor. Soc.,101, 75–91.
Hsu, C.-P. F., 1981: A numerical study of the role of wave-wave interactions during sudden stratospheric warmings. J. Atmos. Sci.,38, 189–23.
Knudsen, B. M., 1996: Accuracy of arctic stratospheric temperature analyses and the implications for the prediction of polar stratospheric clouds. Geophys. Res. Lett.,23, 3747–3750.
Kouker, W., A. Beck, H. Fischer, and K. Petzoldt, 1995: Downward transport in the upper-stratosphere during the minor warming in February 1979. J. Geophys. Res.,100, 11069–11084.
Leovy, C. B., and P. J. Webster, 1976: Stratospheric long waves: Comparison of thermal structure in the northern and southern hemisphere. J. Atmos. Sci.,33, 1624–1638.
Manney, G. L., J. D. Farrara, and C. R. Mechoso, 1991: The behavior of wave 2 in the Southern Hemisphere stratosphere during winter and spring. J. Atmos. Sci.,48, 976–998.
——, ——, and ——, 1994: Simulations of the February 1979 stratospheric sudden warming—Model comparisons and 3-dimensional evolution. Mon. Wea. Rev.,122, 1115–1140.
——, M. L. Santee, L. Froidevaux, J. W. Waters, and R. W. Zurek, 1996a: Polar vortex conditions during the 1995–1996 Arctic winter: Meteorology and MLS ozone. Geophys. Res. Lett.,23, 3203–3206.
——, R. Swinbank, S. T. Massie, M. E. Gelman, A. J. Miller, R. Nagatani, A. O’Neill, and R. W. Zurek, 1996b: Comparison of U.K. Meteorological Office and U.S. National Meteorological Center stratospheric analyses during northern and southern winter. J. Geophys. Res.,101, 10311–10334.
Matsuno, T., 1971: A dynamical model of the stratospheric sudden warming. J. Atmos. Sci.,28, 1479–1494.
McIntyre, M. E., 1982: How well do we understand the dynamics of stratospheric warmings? J. Meteor. Soc. Japan,60, 37–65.
Miyakoda, K., R. F. Strickler, and G. D. Hembree, 1970: Numerical simulation of the breakdown of a polar-night vortex in the stratosphere. J. Atmos. Sci.,27, 139–154.
Naujokat, B., and K. Labitzke, Eds., 1993: Collection of reports on the stratospheric circulation during the winters 1975/75–1991/92. STEP Handbook, July 1993, SCOSTEP, Urbana, IL.
——, and S. Pawson, 1996: The cold stratospheric winters 1994/1995 and 1995/1996. Geophys. Res. Lett.,23, 3703–3706.
O’Neill, A., and V. D. Pope, 1988: The seasonal evolution of the extra-tropical middle atmosphere. Quart. J. Roy. Meteor. Soc.,114, 1063–1110.
——, W. L. Grose, V. D. Pope, H. Maclean, and R. Swinbank, 1994:Evolution of the stratosphere during northern winter 1991/92 as diagnosed from U.K. Meteorological Office analyses. J. Atmos. Sci.,51, 2800–2817.
O’Sullivan, D., and M. H. Hitchman, 1992: Inertial instability and Rossby-wave breaking in a numerical model. J. Atmos. Sci.,49, 991–1002.
——, and R. E. Young, 1992: Modeling the quasi-biennial oscillation’s effect on the winter stratospheric circulation. J. Atmos. Sci.,49, 2437–2448.
——, and T. J. Dunkerton, 1994: Seasonal development of the extratropical QBO in a numerical model of the middle atmosphere. J. Atmos. Sci.,51, 3706–3721.
Palmer, T. N., G. J. Shutts, and R. Swinbank, 1986: Alleviation of a systematic westerly bias in general circulation and numerical weather prediction models through an orographic gravity wave parametrization. Quart. J. Roy. Meteor. Soc.,112, 1001–1040.
Randel, W. J., 1987: A study of planetary waves in the southern winter troposphere and stratosphere. Part I: Wave structure and vertical propagation. J. Atmos. Sci.,44, 917–935.
——, 1992: Global atmospheric circulation statistics. NCAR Tech. Note NCAR/TN-366+STR. 256 pp.
——, D. E. Stevens, and J. L. Stanford, 1987: A study of planetary waves in the southern winter troposphere and stratosphere. Part II: Life cycles. J. Atmos. Sci.,44, 936–949.
Rosier, S. M., B. N. Lawrence, D. G. Andrews, and F. W. Taylor, 1994: Dynamical evolution of the northern stratosphere in early winter 1991/92, as observed by the Improved Stratospheric and Mesospheric Sounder. J. Atmos. Sci.,51, 2783–2799.
Simmons, A. J., and R. Strüfing, 1983: Numerical forecasts of stratospheric warming events using a model with a hybrid vertical coordinate. Quart. J. Roy. Meteor. Soc.,109, 81–111.
Smith, A. K., 1992: Preconditioning for stratospheric sudden warmings: sensitivity studies with a numerical model. J. Atmos. Sci.,49, 1003–1019.
Stott, P. A., G. C. Watson, I. A. MacKenzie, and R. S. Harwood, 1997: COSMIC: A new three-dimensional mechanistic model of the middle atmosphere with an interactive chemistry scheme. Research Activities in Atmospheric and Oceanic Modelling, A. Staniforth, Ed., CAS/JSC Working Group on Numerical Experimentation Rep. 25, 7.68.
Swinbank, R. S., and A. O’Neill, 1994: A stratosphere–troposphere data assimilation system. Mon. Wea. Rev.,122, 686–702.
Thuburn, J., 1992: EUGCM version 2.0 and EUGCM version 2.1. UGAMP Internal Rep. 27.
——, and K. P. Shine, 1991: The MIDRAD radiation scheme in the EUGCM. UGAMP Internal Rep. 17.
Ushimaru, S., and H. Tanaka, 1994: The role of planetary-waves in the formation of inter-hemispheric asymmetry in ozone distribution. J. Meteorol. Soc. Japan,72, 653–670.
Waugh, D. W., 1997: Elliptical diagnostics of stratospheric polar vortices. Quart. J. Roy. Meteor. Soc.,. 123, 1725–1748.
Zurek, R. W., G. L. Manney, A. J. Miller, M. E. Gelman, and R. M. Nagatani, 1996: Interannual variability of the north polar vortex in the lower stratosphere during the UARS mission. Geophys. Res. Lett.,23, 289–292.