• Efron, B., 1982: The Jackknife, the Bootstrap, and Other Resampling Plans. Society for Industrial and Applied Mathematics, 92 pp.

  • Gershunov, A., N. Schneider, T. Barnett, and M. Latif, 1999: Decadal variability of the Asian monsoon. Preprints, 10th Symp. on Global Change Studies, Dallas, TX, Amer. Meteor. Soc., 124–125.

    • Search Google Scholar
    • Export Citation
  • Hulme, M., T. J. Osborne, and T. C. Johns, 1998: Precipitation sensitivity to global warming: Comparison of observations with HadCM2 simulations,. Geophys. Res. Lett., 25 , 33793382.

    • Search Google Scholar
    • Export Citation
  • Krishna Kumar, K., M. K. Soman, and K. Rupa Kumar, 1995: Seasonal forecasting of Indian summer monsoon rainfall: A review. Weather, 50 , 449466.

    • Search Google Scholar
    • Export Citation
  • ——, Kleeman, R., M. A. Cane, and B. Rajagopalan, 1999a: Epochal changes in Indian monsoon–ENSO precursors. Geophys. Res. Lett., 26 , 7578.

    • Search Google Scholar
    • Export Citation
  • ——, Rajagopolan, B., and M. A. Cane, 1999b: On the weakening relationship between the Indian Monsoon and ENSO. Science, 284 , 21562159.

    • Search Google Scholar
    • Export Citation
  • Krishnamurthy, V., and B. N. Goswami, 2000: Indian monsoon–ENSO relationship on interdecadal timescale. J. Climate, 13 , 579594.

  • Mehta, V. M., and K-M. Lau, 1997: Influence of solar irradiance on the Indian monsoon–ENSO relationship at decadal-multidecadal time scales. Geophys. Res. Lett., 24 , 159162.

    • Search Google Scholar
    • Export Citation
  • Normand, C., 1953: Monsoon seasonal forecasting. Quart. J. Roy. Meteor. Soc., 79 , 463473.

  • Pant, G. B., K. Rupa Kumar, B. Parthasarathy, and H. P. Borgaonkar, 1988: Long-term variability of the Indian summer monsoon and related parameters. Adv. Atmos. Sci., 5 , 469481.

    • Search Google Scholar
    • Export Citation
  • Parthasarathy, B., K. R. Kumar, and A. A. Munot, 1991: Evidence of secular variations in Indian Monsoon rainfall–circulation relationships. J. Climate, 4 , 927938.

    • Search Google Scholar
    • Export Citation
  • Stephenson, D. B., K. Rupa Kumar, F. J. Doblas-Reyes, J-F. Royer, F. Chauvin, and S. Pezzulli, 1999: Extreme daily rainfall events and their impact on ensemble forecasts of the Indian monsoon. Mon. Wea. Rev., 127 , 19541966.

    • Search Google Scholar
    • Export Citation
  • ——, Pavan, V., and R. Bojariu, 2000: Is the North Atlantic oscillation a random walk? Int. J. Climatol., 20 , 118.

  • Walker, G. T., 1924: Correlation in seasonal variations of weather. IV: A further study of world weather. Mem. Indian Meteor. Dept., 24 , 275332.

    • Search Google Scholar
    • Export Citation
  • ——, and Bliss, E. W., 1932: World weather. V. Mem. Roy. Meteor. Soc., 4 , 5384.

  • Wallace, J. M., E. M. Rasmusson, T. P. Mitchell, V. E. Kousky, E. S. Sarachik, and H. von Storch, 1998: On the structure and evolution of ENSO-related climate variability in the tropical Pacific: Lessons from TOGA. J. Geophys. Res., 103 , 14 24114 260. .

    • Search Google Scholar
    • Export Citation
  • Webster, P. J., V. O. Magaña, T. N. Palmer, J. Shukla, R. A. Tomas, M. Yanai, and T. Yasunari, 1998: Monsoons: Processes, predictability, and the prospects for prediction. J. Geophys. Res., 103 , 14 45114 510.

    • Search Google Scholar
    • Export Citation
  • Wunsch, C., 1999: The interpretation of short climate records, with comments on the North Atlantic and Southern Oscillations. Bull. Amer. Meteor. Soc., 80 , 245255.

    • Search Google Scholar
    • Export Citation
  • Yasunari, T., 1990: Impact of the Indian monsoon on the coupled atmosphere/ocean system in the tropical Pacific. Meteor. Atmos. Phys., 44 , 2941.

    • Search Google Scholar
    • Export Citation
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Low-Frequency Modulation of the ENSO–Indian Monsoon Rainfall Relationship: Signal or Noise?

Alexander GershunovClimate Research Division, Scripps Institution of Oceanography, University of California, San Diego, La Jolla, California

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Niklas SchneiderClimate Research Division, Scripps Institution of Oceanography, University of California, San Diego, La Jolla, California

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Tim BarnettClimate Research Division, Scripps Institution of Oceanography, University of California, San Diego, La Jolla, California

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Abstract

Running correlations between pairs of stochastic time series are typically characterized by low-frequency evolution. This simple result of sampling variability holds for climate time series but is not often recognized for being merely noise. As an example, this paper discusses the historical connection between El Niño–Southern Oscillation (ENSO) and average Indian rainfall (AIR). Decades of strong correlation (∼−0.8) alternate with decades of insignificant correlation, and it is shown that this decadal modulation could be due solely to stochastic processes. In fact, the specific relationship between ENSO and AIR is significantly less variable on decadal timescales than should be expected from sampling variability alone.

Corresponding author address: Alexander Gershunov, Climate Research Division, Scripps Institution of Oceanography, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA 92093-0224.Email: sasha@ucsd.edu

Abstract

Running correlations between pairs of stochastic time series are typically characterized by low-frequency evolution. This simple result of sampling variability holds for climate time series but is not often recognized for being merely noise. As an example, this paper discusses the historical connection between El Niño–Southern Oscillation (ENSO) and average Indian rainfall (AIR). Decades of strong correlation (∼−0.8) alternate with decades of insignificant correlation, and it is shown that this decadal modulation could be due solely to stochastic processes. In fact, the specific relationship between ENSO and AIR is significantly less variable on decadal timescales than should be expected from sampling variability alone.

Corresponding author address: Alexander Gershunov, Climate Research Division, Scripps Institution of Oceanography, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA 92093-0224.Email: sasha@ucsd.edu

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