Short-term periodicities in interplanetary, geomagnetic and solar phenomena during solar cycle 24
Abstract
In this paper we study the quasi-periodic variations of sunspot area/number, 10.7 cm solar radio flux, Average Photospheric Magnetic Flux, interplanetary magnetic field ( B z ) and the geomagnetic activity index A p during the ascending phase of the current solar cycle 24. We use both Lomb-Scargle periodogram and wavelet analysis technique and find evidence for a multitude of quasi-periodic oscillations in all the data sets. In high frequency range (10 days to 100 days), both methods yield similar significance periodicities around 20-35 days and 45-60 days in all data sets. In the case of intermediate range, the significant periods were around 100-130 days, 140-170 days and 180-240 days The Morlet wavelet power spectrum shows that all of the above-mentioned periods are intermittent in nature. We find that the well-known "Rieger period" of (150-160 days) and near Rieger periods (130-190 days) were significant in both solar, interplanetary magnetic field and geomagnetic activity data sets during cycle 24. The geomagnetic activity is the result of the solar wind-magnetosphere interaction. Thus the variations in the detected periodicity in variety of solar, interplanetary and geomagnetic indices could be helpful to improve our knowledge of the inter-relationship between various processes in the Sun-Earth-Heliosphere system.
- Publication:
-
Astrophysics and Space Science
- Pub Date:
- March 2015
- DOI:
- 10.1007/s10509-014-2188-0
- Bibcode:
- 2015Ap&SS.356....7C
- Keywords:
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- Sun: activities;
- Sun: magnetic field;
- Sun: sunspots;
- Sun: geomagnetic activities;
- Sun: periodicities