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The sunspot cycle and solar and lunar daily variations inH


Results of sunspot cycle influence on solar and lunar ranges at a low latitude station, Alibag, outside the equatorial electrojet belt, show that the sunspot cycle association in solar ranges is three times that of the lunar ranges in thed- andj-seasons. This is in general agreement with the earlier results for non-polar latitude stations. The association with sunspot number of individual lunar amplitudes is greatest for lunar semidiurnal harmonic in thej-season. During this season, the sunspot cycle influence on lunar variations is more than that on solar variations, thereby indicating that the lunar current is situated at a level more favourable for sunspot cycle influence than the level of the current associated with solar variations. With the increase in solar activity a shift appears in the times of maxima of semidiurnal lunar variation towards a later lunar hour ine- andj-seasons and in the year.

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Rao, D.R.K. The sunspot cycle and solar and lunar daily variations inH . PAGEOPH 98, 146–152 (1972).

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  • Solar Activity
  • Early Result
  • Sunspot Number
  • Daily Variation
  • Sunspot Cycle