Auto-detection of Halo CME Parameters as the Initial Condition of Solar Wind Propagation

Abstract

Halo coronal mass ejections (CMEs) originating from solar activities give rise to geomagnetic storms when they reach the Earth. Variations in the geomagnetic field during a geomagnetic storm can damage satellites, communication systems, electrical power grids, and power systems, and induce currents. Therefore, automated techniques for detecting and analyzing halo CMEs have been eliciting increasing attention for the monitoring and prediction of the space weather environment. In this study, we developed an algorithm to sense and detect halo CMEs using large angle and spectrometric coronagraph (LASCO) C3 coronagraph images from the solar and heliospheric observatory (SOHO) satellite. In addition, we developed an image processing technique to derive the morphological and dynamical characteristics of halo CMEs, namely, the source location, width, actual CME speed, and arrival time at a 21.5 solar radius. The proposed halo CME automatic analysis model was validated using a model of the past three halo CME events. As a result, a solar event that occurred at 03:38 UT on Mar. 23, 2014 was predicted to arrive at Earth at 23:00 UT on Mar. 25, whereas the actual arrival time was at 04:30 UT on Mar. 26, which is a difference of 5 hr and 30 min. In addition, a solar event that occurred at 12:55 UT on Apr. 18, 2014 was estimated to arrive at Earth at 16:00 UT on Apr. 20, which is 4 hr ahead of the actual arrival time of 20:00 UT on the same day. However, the estimation error was reduced significantly compared to the ENLIL model. As a further study, the model will be applied to many more events for validation and testing, and after such tests are completed, on-line service will be provided at the Korean Space Weather Center to detect halo CMEs and derive the model parameters.

Development of Forecast Algorithm for Coronal Mass Ejection Speed and Arrival Time Based on Propagation Tracking by Interplanetary Scintillation g-Value

“…As human activities in space and the number of space assets expand exponentially, the impact of CMEs and preparation for their arrival are becoming increasingly important. Hence, various studies on CME parameters and related consequences have been performed in recent decades (Kim et al 2005;Kim et al 2008;Choi et al 2017;Kim & Chang 2019). Interplanetary (IP) space is filled with background solar wind, which is essentially a plasma stream that is constantly blowing out from the sun and permeating the entire heliosphere.…”

Statistical Analysis of Pc1 Pulsations Observed by a BOH Magnetometer

“…Three wave events were identified in this example once the signal was filtered by an automatic detection algorithm. Such algorithm has been applied in previous studies focusing on Sun-Earth connections (e.g., based on coronal mass ejection (CMEs) and solar wind propagation)(Choi et al 2017). The first event started at 18:38 UT and lasted for ~53 minutes, the second started at 19:33 and lasted for ~11 minutes, and the third started at 19:48 UT and lasted for ~37 minutes.…”