Prediction of the Transit Time of Coronal Mass Ejections with an Ensemble Machine-learning Method

Abstract

Coronal mass ejections (CMEs), a kind of violent solar eruptive activity, can exert a significant impact on space weather. When arriving at the Earth, they interact with the geomagnetic field, which can boost the energy supply to the geomagnetic field and may further result in geomagnetic storms, thus having potentially catastrophic effects on human activities. Therefore, accurate forecasting of the transit time of CMEs from the Sun to the Earth is vital for mitigating the relevant losses brought by them. XGBoost, an ensemble model that has better performance in some other fields, is applied to the space weather forecast for the first time. During multiple tests with random data splits, the best mean absolute error (MAE) of ∼5.72 hr was obtained, and in this test, 62% of the test CMEs had absolute arrival time error of less than 5.72 hr. The average MAE over all random tests was ∼10 hr. It indicates that our method has a better predictive potential and baseline. Moreover, we introduce two effective feature importance ranking methods. One is the information gain method, a built-in method of ensemble models. The other is the permutation method. These two methods combine the learning process of the model and its performance to rank the CME features, respectively. Compared with the direct correlation analysis on the sample data set, they can help select the important features that closely match the model. These two methods can assist researchers to process large sample data sets, which often require feature selection in advance.

An Algorithm for the Determination of Coronal Mass Ejection Kinematic Parameters Based on Machine Learning

“…Inspired by their work, Yang et al (2018) developed a model for predicting hourly solar wind speeds 4 days in advance. Machine-learning techniques have also been applied in other studies: the prediction of CME arrival times at Earth (Sudar et al 2016;Liu et al 2018;Wang et al 2019a;Fu et al 2021;Yang et al 2023), predictions of solar flares (Bobra & Ilonidis 2016;Huang et al 2018;Park et al 2018;Li et al 2020;Zheng et al 2021), predictions of relativistic electrons at geosynchronous orbit (Shin et al 2016;Bortnik et al 2018;Wei et al 2018;Zhang et al 2020), predictions of geomagnetic activity Gruet et al 2018;Chakraborty & Morley 2020), and predictions of solar wind speeds (Upendran et al 2020;Bailey et al 2021;Sun et al 2022).…”

CAMEL. II. A 3D Coronal Mass Ejection Catalog Based on Coronal Mass Ejection Automatic Detection with Deep Learning

“…Liu et al (2018) utilized the support vector machine to analyze various parameters of CMEs for predicting the transit time of CMEs from the Sun to the Earth. Yang et al (2023) employed the ensemble learning method XGBoost and introduced two effective feature importance ranking methods.…”