Dr. Scott McIntosh (PhD in Astrophysics) is the Deputy Director (Admin. & Strategic Implementation) of the National Center for Atmospheric Research, High Altitude Observatory and the former Director of the High Altitude Observatory Sun Earth Lab. He has authored or co-authored over 100 journal articles. In regard to his most recent research he gave a Zoom presentation to the Front Range 6 Meter group on 11-November-2020. The title of Dr. McIntosh’s talk was “Solar Cycle 25 Prediction and Why It Will Be Huge!” The prediction he made for the amplitude of Solar Cycle 25 was nothing short of amazing!
Dr. McIntosh recently co-authored a paper which has been submitted for publication in Solar Physics, A Journal for Solar and Solar-Stellar Research and the Study of Solar-Terrestrial Physics. The title is “Overlapping Magnetic Activity Cycles and the Sunspot Number: Forecasting Sunspot Cycle 25 Amplitude.” Below is the abstract of that paper:
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 community wide 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.
You can download the entire paper here – Amplitude.pdf After participating in the Zoom meeting, here are my personal “take-aways” from Dr. McIntosh’s presentation.
1. The “Hale” cycle is the fundamental (mode) driver of solar activity – NOT sunspots. It is a 22-year cycle. – 2. When each Hale cycle comes to an end, that is the beginning of the next explosion of sunspots. – 3. The end of the Hale cycle is called a “Terminator.” One of the slides in the presentation said: “This terminator rapidly triggers growth and emergence of magnetism at mid (~30-35°) and high (~55°) latitudes – within one solar rotation.” – 4. The further apart in time between successive Terminators means the next solar cycle will be weaker. Conversely, the shorter the distance between two Terminators, the greater the amplitude of the ensuing Solar Cycle.
In the image below, the purple vertical dotted lines are the Terminators. Look at the spaces between adjacent Terminators. When you see a large space (more time) the next solar cycle has a smaller amplitude. The scale on the left shows Monthly Sunspots. The orange dots are the maximum of each cycle. NOTE: 1954’s Cycle 19 was the biggest cycle anyone can remember.
5. The Green dot on the right edge of the chart is the prediction of NASA and other Solar Cycle predictors for upcoming Cycle 25. – 6. The last Terminator was in 2011, just 9 years ago. Look how narrow the Terminator lines are for Cycle 24. Tight together, right. – 7. That is because the next Terminator IS HAPPENING RIGHT NOW! Maybe within the next 30 days! – 8. WAY above the Green Dot is a Purple Dot. That is what Dr. McIntosh says his data shows for the peak of Cycle 25 – WOWZER! – 9. He predicts (with 95% confidence) that the sunspots for Cycle 25 will fall between 159 and 310 and (with 68% confidence) it will fall between 211 and 257. His best estimate is a sunspot number of 233 for the peak and the solar flux could hit 275 to 300 !! OH, and he says his algorithm tends to err on the low side so it might even be higher. – 10. This cycle could be in the top 6 or 7 of all time! – 11. Once the terminator occurs (NOW) the new cycle starts fast. He said, “As the terminator happens, the sun goes wonkers.” It will hit the peak in 2023 and the ramp up will be VERY significant.
When a Hale cycle ends the Terminator is triggered and the corona responds almost instantly to the ramp up in global solar flux. Are we there yet? Below is a graph of the Daily Averaged Penticton 10.7cm Solar Radio Flux for the last 5 months up to 10-November-2020. It certainly does seem that the end of the current Hale cycle is upon us.
From their deductions, Dr. McIntosh and his team created an algorithm that could be used to predict Solar Cycle Maxima. All they need to know is when the Terminators happen. They ran that algorithm on the data for all known solar cycles and it was “spot on.” Having their predictions coincide with data which was measured in the past gives a high correlation that the algorithm is accurate.
If these predictions are correct for Solar Cycle 25, it is very, VERY good news for ham radio. BUT – it may be BAD NEWS for our society which is highly dependent on technology. This prediction is a warning for power companies. In 1989 the entire province of Quebec, Canada, had an electrical power blackout cause by a solar storm. Read NASA’s description HERE. Satellites are also in danger from a more active sun. Not only are their electronics vulnerable, but solar heating of the atmosphere can cause more “drag” on orbiting items and that can cause their orbits to decay.
The Zoom presentation was recorded and you can view it in its entirety at the following link:
Zoom Meeting: Solar Cycle 25 Prediction and Why It Will Be Huge!
The images in this Post were screenshots taken during the Zoom presentation and remain the property of Dr. Scott McIntosh.