其他摘要 | Solar activities are the significant factors affecting space weather. Solar activity has a clear eleven-year periodic behaviour. Solar activity was determined by the solar magnetic field, studying the spatio-temporal variation characteristics of solar multi-scale activities is significant meaning for understanding the dynamic evolution process of the solar magnetic field. We have more opportunities to learn more about the spatial distribution of solar multi-scale activity with the advancement of astronomical observation techniques. The overall level of the sunspot in solar cycle 24 decreased much compared to cycle 23, while the number of coronal ejections increased much compared to solar cycle 23. The evolution of the magnetic field is derived from solar rotation. This paper focuses on the spatial distribution of solar multi-scale magnetic activities by studying the sunspot relative numbers, coronal mass ejection database, and Lyman-𝛼 irradiance. Here, we clear that the normalization factor of the normalized asymmetry index has an unusually large influence on the results of the asymmetry index at very low levels of sunspot activity by studying the relative sunspot numbers over the last hundred years, and we determined that the absolute asymmetry index is the most appropriate index for the research of hemispheric asymmetry. Our results provide a stage of progress in the study of hemispheric asymmetry of solar activity indices over the last 50 years. In addition, quasi-biennial oscillations, around 8.5 years and 30-50 years were found in the hemispheric distribution, this result corroborates the numerical simulations of the dynamo theory. Based on high-quality observations from the Large Angle Spectroscopic Coronagraph at the Solar Heliospheric Observatory from 1996 to 2020, this paper divides coronal mass ejections into regular and specific coronal mass ejections. And find that the hemispheric distribution of regular coronal mass ejections is closely related to the hemispheric distribution of sunspot activity, while the hemispheric distribution of specific coronal mass ejections is not related to the hemispheric distribution of sunspot activity, but is closely related to the coronal and heliospheric environment. The hemispheric asymmetry of coronal mass ejections is mainly caused by special coronal mass ejections, not the regular coronal mass ejections. Besides, high-latitude (associated with polar filament and jets) and low-latitude (associated with sunspot activity) events produce in different source regions, so their hemispheric distributions do have different features implying that the hemispheric distribution of coronal mass ejections is a function of the latitude. The dominant hemisphere, cumulative trend, and amplitude distribution of coronal mass ejections differ significantly during different solar cycles, indicating that the heliospheric environment, photospheric magnetic field, and meridional circulation play an important role in the evolution of coronal mass ejections. The investigation of the source locations of halo coronal mass ejections shows that the hemispheric distribution of source locations of the halo coronal mass ejections is also asymmetrical, and the source locations of the halo coronal mass ejections are mainly concentrated in the latitudes of the solar activity region, which is closely related to the sunspot activity, and there is no ”rush to the polar region” phenomenon exists in the distribution of the source locations of halo coronal mass ejections. The investigation of the Lyman-𝛼 irradiance from 1947 to 2023 shows that there are two rotation signals of 27.8 and 13.9 days for the solar transition region. The periodic signal of 13 days was obvious in the works of the periodicity behavior of the solar wind velocities and interplanetary magnetic field. This result suggests that solar rotation of the transition region plays an important role in the solar wind, and provides some guidance for the adjustment of solar wind model parameters. It is also found that the solar rotation of the transition region ranges from 19.25 to 31.25 days (mean value is 25.45 days ), with a decreasing trend. The rotation of the solar transition region is closely related to the 11-year cycle of sunspot activity. Coronal mass ejections and solar wind are significant astronomical factors affecting the solar-terrestrial space environment, this paper focuses on the study of the variation of multi-scale solar magnetic activities with solar cycles, especially for the evolution characteristics of the hemispheric distribution of the coronal mass ejections and the rotation of the solar transition region. The results provide new observational results for further understanding the variation of the solar-terrestrial space environment. |
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