Comparing SSN Index to X-ray Flare and Coronal Mass Ejection Rates from Solar Cycles 22-24

TL;DR

This study analyzes the relationship between sunspot numbers and solar activity indicators like X-ray flares and CMEs over solar cycles 22-24, providing updated rates for better prediction of geoeffective events.

Contribution

It introduces revised sunspot-number-dependent flare and CME rates based on recent satellite data, enhancing understanding of solar activity patterns across multiple cycles.

Findings

X-ray flare rates correlate with sunspot number across three cycles.

CME properties such as speed and width are linked to sunspot activity.

X-ray background flux strongly correlates with sunspot number.

Abstract

The newly revised sunspot number series allows for placing historical geoeffective storms in the context of several hundred years of solar activity. Using statistical analyses of the Geostationary Operational Environmental Satellites (GOES) X-ray observations from the past ~30 years and the Solar and Heliospheric Observatory (SOHO) Large Angle and Spectrometric Coronagraph (LASCO) Coronal Mass Ejection (CME) catalog (1996-present), we present sunspot-number-dependent flare and CME rates. In particular, we present X-ray flare rates as a function of sunspot number for the past three cycles. We also show that the 1-8 AA X-ray background flux is strongly correlated with sunspot number across solar cycles. Similarly, we show that the CME properties (e.g., proxies related to the CME linear speed and width) are also correlated with sunspot number for SC 23 and 24. These updated rates will enable future predictions for geoeffective events and place historical storms in the context of present solar activity.