The Analysis of Interplanetary Shocks Associated with Six Major Geo-Effective Coronal Mass Ejections during Solar Cycle 24

Abstract

A Coronal Mass Ejection (CME) is an ejection of energetic plasma with magnetic field from the Sun. In traversing the Sun-Earth distance, the kinematics of the CME is immensely important for the prediction of space weather. The objective of the present work is to study the propagation properties of six major geo-effective CMEs and their associated interplanetary shocks which were observed during solar cycle 24. These reported CME events produced intense geo-magnetic storms (Dst > 140 nT). The six CME events have a broad range of initial linear speeds ~600-2700 km/sec in the LASCO/SOHO field of view, comparing two slow CMEs (speed ~579 km/sec and 719 km/sec), three moderate speed CMEs (speed ~1366, 1571, 1008 km/sec), and one fast CME (speed ~2684 km/sec). The actual arrival time of the reported events is compared with the arrival time calculated using the Empirical Shock Arrival model (ESA model). For acceleration estimation, we utilize three different acceleration-speed equations reported in the previous literatures for different acceleration cessation distance (ACD). In addition, we compared the transit time estimated using the second-order speed of CMEs with observed transit time. We also compared the observed transit time with transit time obtained from various shock arrival model. From our present study, we found the importance of acceleration cessation distance for CME propagation in interplanetary space and better acceleration speed for transit time calculation than other equations for CME forecasting.

Geoeffectiveness Prediction of CMEs

“…Syed Ibrahim et al (2019 found that the ICME transit-time decreases with the increase in the CME initial speed, although a broad range of transit times were observed for a given CME speed. For slow CMEs ( < 400 km/s), the energy is transferred from the solar wind to the CMEs, while faster events (P400 km/s) tend to lose their energy to the ambient medium (e.g., Soni et al, 2019).…”

Exhaustive study of three-time periods of solar activity due to single active regions: sunspot, flare, CME, and geo-effectiveness characteristics

“…However Weak and moderate storms could be caused by both CMEs and co-rotating interaction regions (CIRs) (Gosling et al, 1990). Primary requirements for the geo-effectiveness of CMEs are (1) the CME must be reach at Earth and (2) having southward component of their magnetic field (Soni et al, 2019). To determine the geo-magnetic effects of CMEs, we consider the minimum Dst values 1-5 days after the CME onsets.…”