Temporal Offsets between Maximum CME Speed Index and Solar, Geomagnetic, and Interplanetary Indicators during Solar Cycle 23 and the Ascending Phase of Cycle 24

TL;DR

This study investigates the timing differences between the maximum CME speed index and various solar, interplanetary, and geomagnetic indicators during Solar Cycle 23 and the early phase of Cycle 24, revealing a hysteresis phenomenon.

Contribution

It introduces an analysis of temporal offsets and hysteresis effects between CME speed and other solar and geomagnetic activity indicators across solar cycle phases.

Findings

Identified a hysteresis phenomenon linking CME speed and other indices.

Observed different paths for parameters during ascending and descending phases of cycle 23.

Highlighted the potential physical processes connecting solar activity to geomagnetic responses.

Abstract

On the basis of morphological analysis of yearly values of the maximum CME (coronal mass ejection) speed index, the sunspot number and total sunspot area, sunspot magnetic field, and solar flare index, the solar wind speed and interplanetary magnetic field strength, and the geomagnetic Ap and Dst indices, we point out the particularities of solar and geomagnetic activity during the last cycle 23, the long minimum which followed it and the ascending branch of cycle 24. We also analyze temporal offset between the maximum CME speed index and the above-mentioned solar, geomagnetic, and interplanetary indices. It is found that this solar activity index, analyzed jointly with other solar activity, interplanetary parameters, and geomagnetic activity indices, shows a hysteresis phenomenon. It is observed that these parameters follow different paths for the ascending and the descending phases of solar cycle 23. It is noticed that the hysteresis phenomenon represents a clue in the search for physical processes responsible for linking the solar activity to the near-Earth and geomagnetic responses.