• Afraimovich, V. S., N. N. Verichev, and M. I. Rabinovich, 1986: Stochastic synchronization of oscillation in dissipative systems. Radiophys. Quantum Electron.,29, 795–803.

  • Ashwin, P., J. Buescu, and I. Stewart, 1994: Bubbling of attractors and synchronisation of chaotic oscillators. Phys. Lett. A,193, 126–139.

  • Bjerknes, J., 1969: Atmospheric teleconnections from the equatorial Pacific. Mon. Wea. Rev.,97, 163–172.

  • Brown, R., N. F. Rulkov, and N. B. Tufillaro, 1994a: The effects of additive noise and drift in the dynamics of the driving on chaotic synchronization. Phys. Lett. A,196, 201–205.

  • ——, ——, and ——, 1994b: Synchronization of chaotic systems: The effects of additive noise and drift in the dynamics of the driving. Phys. Rev. E,50, 4488–4508.

  • Charney, J. G., and J. G. DeVore, 1979: Multiple flow equilibria in the atmosphere and blocking. J. Atmos. Sci.,36, 1205–1216.

  • Coughlan, M. J., 1983: A comparative climatology of blocking action in the two hemispheres. Aust. Meteor. Mag.,31, 3–13.

  • de Swart, H. E., 1988: Low-order spectral models of the atmospheric circulation: A survey. Acta Appl. Math.,11, 49–96.

  • ——, 1989: CWI Tract 60: Vacillation and Predictability Properties of Low-Order Atmospheric Spectral Models. Stichting Mathematisch Centrum, 121 pp.

  • Duane, G. S., 1997: Synchronized chaos in extended systems and meteorological teleconnections. Phys. Rev. E,56, 6475–6493.

  • Fujisaka, H., and T. Yamada, 1983: Stability theory of synchronized motion in coupled-oscillator systems. Prog. Theor. Phys.,69, 32–47.

  • Hoskins, B. J., and D. J. Karoly, 1981: The steady linear response of a spherical atmosphere to thermal and orographic forcing. J. Atmos. Sci.,38, 1179–1196.

  • Jin, F.-F., J. D. Neelin, and M. Ghil, 1994: ENSO on the devil’s staircase. Science,264, 70–72.

  • Kalnay, E., and Coauthors, 1996: The NCEP/NCAR 40-year reanalysis project. Bull. Amer. Meteor. Soc.,77, 437–471.

  • Kiladis, G. N., and K. M. Weickmann, 1992: Extratropical forcing of tropical Pacific convection during northern winter. Mon. Wea. Rev.,120, 1924–1938.

  • Kocarev, L., Z. Tasev, and U. Parlitz, 1997: Synchronizing spatiotemporal chaos of partial differential equations. Phys. Rev. Lett.,79, 51–54.

  • Legras, B., and M. Ghil, 1985: Persistent anomalies, blocking and variations in atmospheric predictability. J. Atmos. Sci.,42, 433–471.

  • Lorenz, E. N., 1991: Dimension of weather and climate attractors. Nature,353, 241–244.

  • Morgul, O., and M. Feki, 1997: Synchronization of chaotic systems by using occasional coupling. Phys. Rev. E,55, 5004–5010.

  • Morse, P. M., and H. Feshbach, 1953: Green functions. Methods of Theoretical Physics, McGraw-Hill, 795–803.

  • Palmer, T. N., 1993: Extended-range atmospheric prediction and the Lorenz model. Bull. Amer. Meteor. Soc.,74, 49–65.

  • Pecora, L. M., and T. L. Carroll, 1990: Synchronization in chaotic systems. Phys. Rev. Lett.,64, 821–824.

  • Rex, D. F., 1950: Blocking action in the middle troposphere and its effect upon regional climate. Part I: An aerological study of blocking action. Tellus,2, 196–211.

  • Rulkov, N. F., M. M. Sushchik, and L. S. Tsimring, 1995: Generalized synchronization of chaos in directionally coupled chaotic systems. Phys. Rev. E,51, 980–994.

  • Sushchik, M. M., 1996: Synchronized chaotic oscillations. Ph. D. dissertation, University of California, San Diego, 174 pp. [Available from University of California at San Diego, La Jolla, CA 92093.].

  • Tibaldi, S., and F. Molteni, 1990: On the operational predictability of blocking. Tellus,42A, 343–365.

  • Treidl, R. A., E. C. Birch, and P. Sajecki, 1981: Blocking action in the Northern Hemisphere: A climatological study. Atmos.–Ocean,19, 1–23.

  • Tziperman, E., M. A. Cane, and S. Zebiak, 1995: Irregularity and locking to the seasonal cycle in an ENSO prediction model as explained by the quasi-periodicity route to chaos. J. Atmos. Sci.,52, 293–306.

  • ——, H. Scher, S. E. Zebiak, and M. A. Cane, 1997: Controlling spatiotemporal chaos in a realistic El Niño prediction model. Phys. Rev. Lett.,79, 1034–1037.

  • van Loon, H., 1956: Blocking action in the Southern Hemisphere Pt. 1. Notos,5, 171–178.

  • Venkataramani, S. C., B. R. Hunt, and E. Ott, 1996: Bubbling transition. Phys. Rev. E,54, 1346–1360.

  • Walker, G. T., 1924: Correlation in seasonal variations of weather: A further study of world weather. Memoirs of the India Meteorological Department, India Meteorological Dept., 275–332.

  • Webster, P. J., 1981: Mechanisms determining the atmospheric response to sea surface temperature anomalies. J. Atmos. Sci.,38, 554–571.

  • ——, 1982: Seasonality in the local and remote atmospheric response to sea surface temperature anomalies. J. Atmos. Sci.,39, 41–52.

  • ——, and J. L. Keller, 1974: Strong long-period tropospheric and stratospheric rhythm in the Southern Hemisphere. Nature,248, 212–213.

  • ——, and J. R. Holton, 1982: Cross-equatorial response to middle-latitude forcing in a zonally varying basic state. J. Atmos. Sci.,39, 722–733.

  • ——, and S. Yang, 1992: Monsoon and ENSO: Selectively interacting systems. Quart. J. Roy. Meteor. Soc.,118, 877–926.

  • ——, and H.-R. Chang, 1998: Atmospheric wave propagation in heterogeneous flow: Basic flow controls on tropical–extratropical interaction and equatorial wave modification. Dyn. Atmos. Oceans,27, 91–134.

  • Wright, A. D. F., 1974: Blocking action in the Australian region. Australian Bureau Meteorology Tech. Rep. 10, 29 pp. [Available from Bureau of Meteorology, G.P.O. Box 1289K, Melbourne, VIC 3001, Australia.].

  • Yasunari, T., 1990: Impact of Indian monsoon on the coupled atmosphere/ocean system in the tropical Pacific. Meteor. Atmos. Phys.,44, 29–41.

  • Zebiak, S. E., and M. A. Cane, 1987: A model El Niño–Southern Oscillation. Mon. Wea. Rev.,115, 2262–2278.

All Time Past Year Past 30 Days
Abstract Views 0 0 0
Full Text Views 107 107 4
PDF Downloads 7 7 4

Co-occurrence of Northern and Southern Hemisphere Blocks as Partially Synchronized Chaos

View More View Less
  • 1 Program in Atmospheric and Oceanic Sciences, University of Colorado, Boulder, Colorado
© Get Permissions
Restricted access

Abstract

Teleconnections between the midlatitudes of the Northern and Southern Hemispheres are diagnosed in National Centers for Environmental Prediction–National Center for Atmospheric Research reanalysis data and separately in European Centre for Medium-Range Weather Forecasts reanalysis data. The teleconnections are manifested as a small but significant tendency for blocking to occur simultaneously in the two hemispheres, though at different longitudes and different relative latitudes, during boreal winters over the period 1979–94 in both datasets.

One way to explain the correlations between blocking events is as an instance of synchronized chaos, the tendency of some coupled chaotic systems to synchronize, permanently or intermittently, regardless of initial conditions. As the coupling is weakened, the systems no longer synchronize completely, but small correlations between the states of the coupled systems are observed instead. In previous work, such behavior was observed in an idealized coupled-hemisphere model constructed from a midlatitude model due to de Swart, which extended the earlier Charney–DeVore spectral truncation of the barotropic vorticity equation by including a few extra modes. The direct coupling of the two midlatitude systems in the coupled-hemisphere model represented the exchange of Rossby waves through the upper-tropospheric “westerly ducts” in the Tropics.

Significant correlations are found between blocking events, which are chaotically timed in each hemisphere considered singly, even without several of the idealizations used in the previous study. In a model modified to include an extended tropical region, the correlations are little affected by attenuation and phase shift of the Rossby waves that couple the two midlatitude systems. Variations in the relative longitudes of topographic features in the two hemispheres leave significant correlations or anticorrelations. The annual cycle, which imposes directionality on the coupling, since the Northern Hemisphere is more strongly forced than the Southern Hemisphere at the times when the hemispheres are coupled, increases the correlations slightly. A two-hemisphere model constructed from a higher-order (wavenumber 3) truncation of the barotropic vorticity equation exhibits regime transitions between blocked and zonal flow at a more realistic rate in each hemisphere but still exhibits interhemispheric correlations.

* Current affiliation: National Center for Atmospheric Research, Boulder, Colorado.

Corresponding author address: Gregory S. Duane, Advanced Study Program, National Center for Atmospheric Research, P.O. Box 3000, Boulder, CO, 80307-3000.

Email: gduane@ucar.edu

Abstract

Teleconnections between the midlatitudes of the Northern and Southern Hemispheres are diagnosed in National Centers for Environmental Prediction–National Center for Atmospheric Research reanalysis data and separately in European Centre for Medium-Range Weather Forecasts reanalysis data. The teleconnections are manifested as a small but significant tendency for blocking to occur simultaneously in the two hemispheres, though at different longitudes and different relative latitudes, during boreal winters over the period 1979–94 in both datasets.

One way to explain the correlations between blocking events is as an instance of synchronized chaos, the tendency of some coupled chaotic systems to synchronize, permanently or intermittently, regardless of initial conditions. As the coupling is weakened, the systems no longer synchronize completely, but small correlations between the states of the coupled systems are observed instead. In previous work, such behavior was observed in an idealized coupled-hemisphere model constructed from a midlatitude model due to de Swart, which extended the earlier Charney–DeVore spectral truncation of the barotropic vorticity equation by including a few extra modes. The direct coupling of the two midlatitude systems in the coupled-hemisphere model represented the exchange of Rossby waves through the upper-tropospheric “westerly ducts” in the Tropics.

Significant correlations are found between blocking events, which are chaotically timed in each hemisphere considered singly, even without several of the idealizations used in the previous study. In a model modified to include an extended tropical region, the correlations are little affected by attenuation and phase shift of the Rossby waves that couple the two midlatitude systems. Variations in the relative longitudes of topographic features in the two hemispheres leave significant correlations or anticorrelations. The annual cycle, which imposes directionality on the coupling, since the Northern Hemisphere is more strongly forced than the Southern Hemisphere at the times when the hemispheres are coupled, increases the correlations slightly. A two-hemisphere model constructed from a higher-order (wavenumber 3) truncation of the barotropic vorticity equation exhibits regime transitions between blocked and zonal flow at a more realistic rate in each hemisphere but still exhibits interhemispheric correlations.

* Current affiliation: National Center for Atmospheric Research, Boulder, Colorado.

Corresponding author address: Gregory S. Duane, Advanced Study Program, National Center for Atmospheric Research, P.O. Box 3000, Boulder, CO, 80307-3000.

Email: gduane@ucar.edu

Save