Forecasting Sunspot Cycle 25

George N2APB

Here is some incredibly positive news on the upcoming Solar Cycle 25 is deduced in a fascinating paper at 


Abstract and an amazing graphic is copied below showing some analysis using Hilbert Transform DSP processing of the 11-yer minima and maxima of the solar cycles. 

// Look at the purple dot at the right side of the graph below … This is what they are forecasting sunspot activity (and HF propagation) to be in several years!


73, George N2APB

TLARC CPO  (Chief Propagation Officer)



ABSTRACT … The Sun exhibits a well-observed modulation in the number of sunspots over a period of about 11 years. From the dawn of modern observational astronomy sunspots have presented a challenge to understanding – their quasi-periodic variation in number, first noted 160 years ago, stimulates communitywide interest to this day. A large number of techniques are able to explain the temporal landmarks, (geometric) shape, and amplitude of sunspot “cycles,” however forecasting these features accurately in advance remains elusive. Recent observationally-motivated studies have illustrated a relationship between the Sun’s 22-year (Hale) magnetic cycle and the production of the sunspot cycle landmarks and patterns, but not the amplitude of the cycle. Using (discrete) Hilbert transforms on 270 years of (monthly) sunspot numbers to robustly identify the so-called “termination” events, landmarks marking the start and end of sunspot and magnetic activity cycles, we extract a relationship between the temporal spacing of terminators and the magnitude of sunspot cycles. Given this relationship and our prediction of a terminator event in 2020, we deduce that sunspot cycle 25 will have a magnitude that rivals the top few since records began. This outcome would be in stark contrast to the community consensus estimate of sunspot cycle 25 magnitude