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The Sun constantly releases radiation and plasma into the heliosphere. Sporadically, the Sun launches solar eruptions such as flares and coronal mass ejections (CMEs). CMEs carry away a huge amount of mass and magnetic flux with them. An Earth-directed CME can cause serious consequences to the human system. It can destroy power grids/pipelines, satellites, and communications. Therefore, accurately monitoring and predicting CMEs is important to minimize damages to the human system. In this study we propose an ensemble learning approach, named CMETNet, for predicting the arrival time of CMEs from the Sun to the Earth. We collect and integrate eruptive events from two solar cycles, #23 and #24, from 1996 to 2021 with a total of 363 geoeffective CMEs. The data used for making predictions include CME features, solar wind parameters and CME images obtained from the SOHO/LASCO C2 coronagraph. Our ensemble learning framework comprises regression algorithms for numerical data analysis and a convolutional neural network for image processing. Experimental results show that CMETNet performs better than existing machine learning methods reported in the literature, with a Pearson product-moment correlation coefficient of 0.83 and a mean absolute error of 9.75 h.
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Variability of East–West Asymmetry in Energetic Storm Particle Intensities and Coronal Mass Ejection Deflection during Solar Cycles 23 and 24
Abstract We investigate the variability of the east–west asymmetry in energetic storm particle (ESP) heavy ion intensities at interplanetary shocks driven by coronal mass ejections (CMEs) during solar cycles (SCs) 23 and 24. We analyze helium (He), oxygen (O), and iron (Fe) intensities in the energy range of ∼0.13–3 MeV/nucleon, using observations from NASA’s ACE and STEREO missions. We examine the longitudinal distribution of ESP intensities and their correlation with the near-Sun CME speed and average transit CME speed, distinguishing between eastern and western events. Our results reveal significant differences in the east–west asymmetry of ESP intensities between SC 23 and SC 24. This shift is linked to changes in the heliolongitude distribution of the CME Speed Ratio (the ratio of CME average transit speed to near-Sun speed), which transitions from peaking predominantly in the western heliosphere in SC 23 to the eastern heliosphere in SC 24. This shift suggests a systematic difference in CME deflection between the two cycles, with CMEs in SC 23 being, on average, deflected eastward, while those in SC 24 exhibit a tendency for westward deflection.
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- Award ID(s):
- 2301382
- PAR ID:
- 10667777
- Publisher / Repository:
- IOPScience
- Date Published:
- Journal Name:
- The Astrophysical Journal
- Volume:
- 997
- Issue:
- 2
- ISSN:
- 0004-637X
- Page Range / eLocation ID:
- 223
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript
- Journal Article:
- https://doi.org/10.3847/1538-4357/ae25f4
