The Termination Event has Arrived
MrPlow writes in with a submission, via IRC, for boru.
Looks like solar cycle 24 has finally ended.
The Termination Event has Arrived:
The "Termination Event" is a new idea in solar physics, outlined by McIntosh and Leamon in a December 2020 paper in the journal Solar Physics. Not everyone accepts it-yet. If Solar Cycle 25 unfolds as McIntosh and Leamon predict, the Termination Event will have to be taken seriously.
The basic idea is this: Solar Cycle 25 (SC25) started in Dec. 2019. However, old Solar Cycle 24 (SC24) refused to go away. It hung on for two more years, producing occasional old-cycle sunspots and clogging the sun's upper layers with its decaying magnetic field. During this time, the two cycles coexisted, SC25 struggling to break free while old SC24 held it back.
[...] Researchers have long known that solar cycles can overlap. The twist added by McIntosh and Leamon is the realization that overlapping cycles interact. [...] In the early 20th century, George Ellery Hale discovered that the magnetic polarity of sunspot pairs reverses itself from one cycle to the next; indeed, the sun's entire global magnetic field flips every ~11 years.
[...] Termination Events mark the end of interference, when a new cycle can break free of the old.
The timing of the Termination Event can predict the intensity of the new cycle. In their Solar Physics paper, McIntosh and Leamon looked back over 270 years of sunspot data and found that Termination Events happen every 10 to 15 years.
"We found that the longer the time between terminators, the weaker the next cycle would be," explains Leamon. "Conversely, the shorter the time between terminators, the stronger the next solar cycle would be."
Journal Reference:
Scott W. McIntosh, Sandra Chapman, Robert J. Leamon, et al. Overlapping Magnetic Activity Cycles and the Sunspot Number: Forecasting Sunspot Cycle 25 Amplitude [open], Solar Physics (DOI: 10.1007/s11207-020-01723-y)
Read more of this story at SoylentNews.