We appreciate the three anonymous reviewers for their helpful comments. The GFD-DENNOU library (SGKS Group 2001) was used for graphical output. This work was supported in part by the Grant-in-Aid for Scientific Research of the Ministry of Education, Culture, Sports, Science, and Technology (MEXT) of Japan, and by the Kyoto University Active Geosphere Investigations for the 21st Century COE (KAGI 21), which was approved by the MEXT of Japan.
Baldwin, M., T. Hirooka, A. O’Neill, and S. Yoden, 2003: Major stratospheric warming in the Southern Hemisphere in 2002: Dynamical aspects of the ozone hole split. SPARC Newsletter, No. 20, SPARC Office, Toronto, ON, Canada, 24–26.
Bernardet, P., A. Butet, M. D’equé, M. Ghil, and R. L. Pfeffer, 1990: Low-frequency oscillations in a rotating annulus with topography. J. Atmos. Sci., 47 , 3023–3043.
Hio, Y., and I. Hirota, 2002: Interannual variations of planetary waves in the Southern Hemisphere stratosphere. J. Meteor. Soc. Japan, 80 , 1013–1027.
Hio, Y., and S. Yoden, 2004: Quasiperiodic variations of the polar vortex in the Southern Hemisphere stratosphere due to wave–wave interaction. J. Atmos. Sci., 61 , 2510–2527.
Hio, Y., and S. Yoden, 2005: Interannual variations of the seasonal march in the Southern Hemisphere stratosphere for 1979–2002 and characterization of the unprecedented year 2002. J. Atmos. Sci., 62 , 567–580.
Ishioka, K., and S. Yoden, 1995: Non-linear aspects of a barotropically unstable polar vortex in a forced-dissipative system: Flow regimes and tracer transport. J. Meteor. Soc. Japan, 73 , 201–212.
Juckes, M. N., and M. E. McIntyre, 1987: A high-resolution one-layer model of breaking planetary waves in the stratosphere. Nature, 328 , 590–596.
Li, G. Q., R. Kung, and R. L. Pfeffer, 1986: An experimental study of baroclinic flows with and without wave-two bottom topography. J. Atmos. Sci., 42 , 433–471.
Manney, G. L., T. R. Nathan, and J. L. Stanford, 1988: Barotropic stability of realistic stratospheric jets. J. Atmos. Sci., 45 , 2545–2555.
Manney, G. L., C. R. Mechoso, L. S. Elson, and J. D. Farrara, 1991: Planetary-scale waves in the Southern Hemisphere winter and early spring stratosphere: Stability analysis. J. Atmos. Sci., 48 , 2509–2523.
Mizuta, R., and S. Yoden, 2001: Chaotic mixing and transport barriers in an idealized stratospheric polar vortex. J. Atmos. Sci., 58 , 2615–2628.
Prieto, R., and W. H. Schubert, 2001: Analytical predictions for zonally symmetric equilibrium states of the stratospheric polar vortex. J. Atmos. Sci., 58 , 2709–2728.
SGKS Group, cited. 2001: DCL-5.2 (in Japanese). GFDDENNOU Club. [Available online at http://www.gfd-dennou.org/library/dcl/.].
Shiotani, M., N. Shimoda, and I. Hirota, 1993: Interannual variability of the stratospheric circulation in the southern hemisphere. Quart. J. Roy. Meteor. Soc., 119 , 531–546.
Thuburn, J., and V. Lagneau, 1999: Eulerian mean, contour integral, and finite-amplitude wave activity diagnostics applied to a single-layer model of the winter stratosphere. J. Atmos. Sci., 56 , 689–710.
Yoden, S., 1983a: Nonlinear interactions in a two-layer, quasi-geostrophic, low-order model with topography. Part I: Zonal flow-forced wave interactions. J. Meteor. Soc. Japan, 61 , 1–18.
Yoden, S., 1983b: Nonlinear interactions in a two-layer, quasi-geostrophic, low-order model with topography. Part II: Interactions between zonal flow, forced waves and free waves. J. Meteor. Soc. Japan, 61 , 19–35.
Yoden, S., 1985a: Bifurcation properties of a quasi-geostrophic, barotropic, low-order model with topography. J. Meteor. Soc. Japan, 63 , 535–546.
Yoden, S., 1985b: Multiple stable states of quasi-geostrophic barotropic flow over sinusoidal topography. J. Meteor. Soc. Japan, 63 , 1031–1045.
Yoden, S., and K. Ishioka, 1993: A numerical experiment on the breakdown of a polar vortex due to forced Rossby waves. J. Meteor. Soc. Japan, 71 , 59–72.