Abstract Details


Name: Saurabh Tripathi
Affiliation: Indian Institute of Astrophysics, Bengaluru
Conference ID: TVS202510146
Title: An Investigation into the Solar Origins of Geo-Effective Coronal Mass Ejections during 1997–2024
Authors and Co-Authors: Dr. Tanmoy Samanta, Saurabh Tripathi
Abstract Type: Contributory Presentation
Abstract: Coronal mass ejections (CMEs) are large-scale eruptions from the solar atmosphere that can trigger intense geomagnetic storms (GMS), causing severe disruptions to space- and ground-based technologies. Therefore, understanding their origin, propagation, and evolution through the interplanetary medium is essential for early forecasting. In this study, we present a statistical analysis of geoeffective CMEs from 1997 to 2024. We investigate their solar sources, heliospheric propagation, and subsequent evolution into Interplanetary CMEs(ICMEs), detected at L1 via in-situ signatures. Using multi-instrument observations and established catalogs, we examine source-region properties and explore the relationship of storm intensity with flare class, CME speed, and longitudinal dependency. Although the background solar wind strongly influences the CME transit time from the Sun to L1, we find that CME and ICME speeds remain tightly correlated. Our detailed investigation shows that transit time follows a hyperbolic dependence on velocity, contrary to the earlier suggested linear relations, yielding more accurate arrival-time estimates. Our result further reveals a clear longitudinal asymmetry, with geoeffective CMEs more likely to originate from the western hemisphere. Storm intensity depends moderately on flare class and speed, with faster CMEs producing stronger GMS. Interestingly, the declining phase of Solar Cycles 23 and 24 produces more intense storms than their rising phase, primarily associated with fast CMEs and possibly linked to large-scale magnetic restructuring during the Sun’s polarity reversal. These results, offering new insights into the link between solar activity and space weather, contribute to developing improved predictive models for intense geomagnetic storms.