Is there more global solar activity on the Sun?

Abstract

Abstract. There appear indications of more global activity on the Sun which is larger, much beyond the scale of solar active regions (ARs). These indications include formation, flaring and eruption of the trans-equatorial loops seen in EUV and X-rays, formation and eruption of transequatorial filaments, global magnetic connectivity in EUV dimming associated with halo-coronal mass ejections, wide spread of radio burst sources in meter wavelength in the solar corona, and quasi-simultaneous magnetic flux emergence in both hemispheres seen during some major solar events. With examples of a few major events in the last solar cycle we discuss the possibility that there is large or global-scale activity on the Sun. Its spatial scale is many times larger than that of AR and temporal scale is over 10 hours. The exemplified trans-equatorial loops are anchored in ARs and their activity is temporally associated with flares in ARs too. In some sense the flares in ARs appear either as a part of or a precursor of the more global activity. It is likely that the combination of the flares in ARs and the associated global activity is responsible to the major solar-terrestrial events. More efforts in understanding the global activity are undertaken.

空间天气驱动源—太阳风暴研究

“…图 12 显示了云南天文台观测到的 跨赤道暗条(环)的形成和爆发 [125] . 依据推测, Wang 等 [125,126] 提出了跨越活动区或跨越赤道的"大尺度活 https://engine.scichina.com/doi/10.1360/zd-2013-43-6-883 动"(global activity)的概念, 表现为在 EUV 和软 X 射 线所观测到的跨赤道磁环的形成、增亮和爆发 [127] , 与晕状 CME 相关的暗区的磁场连接 [128] , 大规模的米 波爆发 [129] , 以及准同时的发生在南北半球的在大耀斑 期间的磁通量浮现 [130] . 这些大尺度活动在时间上持续 也很长(达到 10 h).…”