Occurrence of sudden storm commencement in interplanetary space

Sudden storm commencement (SSC) events detected in interplanetary space from 1869 to 2023, are subjected to wavelet and Lomb- Scargle periodogram analyses to determine the potential frequency of their recurrence. This period includes SSC events from the preced- ing fourteen solar cycles. Using Lomb-Scargle periodogram analysis, we have identified SSC occurrences independently during the odd and even solar activity cycles. We also used the wavelet analysis approach throughout the positive (A > 0) and negative (A <0) polarity states of the heliospheric magnetic fields, in addition to solar activity cycles. This study reveals some notable short-term periodic vari- ations in the SSC time series. The findings indicate that SSC occurrences have a conspicuous and important similar to 44.0-day period. We have also observed solar and extended solar rotation periods in the time series, along with some intermittent variations (e.g., similar to 22.0-, similar to 19.0- days). The observed periodicities in the SSC time series are discussed and compared with the previously detected periodicities of solar wind and plasma, geomagnetic activity, and cosmic rays' intensity indicators. (c) 2024 COSPAR. Published by Elsevier B.V. All rights are reserved, including those for text and data mining, AI training, and similar technologies.