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Some aspects of the 30–50 day oscillation

  • S. V. Kasture
  • R. N. Keshavamurty
Article

Abstract

The structure and interannual variability of the 30–50 day oscillation over the Indian region have been studied during the monsoon season. The power spectra of the zonal component of wind show large power in the 30–50 day time scale. The oscillation has a meridional wavelength of about 25° latitude and a slow northward phase speed of about 0.7° latitude per day. The oscillation also has some interannual variability. The periods are somewhat longer during the drought years.

Keywords

Oscillation subseasonal oscillation active break monsoon cycle interannual variability 

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Copyright information

© Indian Academy of Sciences 1987

Authors and Affiliations

  • S. V. Kasture
    • 1
  • R. N. Keshavamurty
    • 1
  1. 1.Physical Research LaboratoryNavrangpura, AhmedabadIndia

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