Speaker
Description
We study magnetic storms during the 120-year time interval (1903-2023), which covers the whole Modern Maximum (MM, the latest Gleissberg cycle) of solar activity. Storms are mainly driven by coronal mass ejections (CME) and high-speed solar wind streams with related stream interaction regions (HSS/SIR). CME occurrence closely follows sunspots, the emergence of new strong magnetic flux, while HSS/SIR occurrence depends on the global structure of solar corona, in particular coronal holes, which is determined by the evolution of solar active regions (plages/faculae). Studying different types of storms during the last century can yield information on the occurrence of CMEs and HSSs both in the growth phase and in the decay phase of the Modern Maximum and, thereby, on the evolution of the Sun during this period of exceptional activity.
We find that the CME storms were relatively more frequent in the MM growth phase than in the decay phase. This is in agreement with the recent finding of the change in the mutual relation of sunspots and plages so that sunspots are relatively more frequent in the growth than the decay phase of the MM. We discuss these results in view of better understanding the solar centennial evolution and the long-term occurrence of CME and HSS/SIR storms at the Earth. We also note on the implications of these findings on the stellar evolution of the Sun and Sun-like stars.
| Do you plan to attend in-person or online? | In-person |
|---|
