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Sunspot update: Higher than predicted activity continues

The uncertainty of science: Time for our monthly update of the Sun’s on-going sunspot cycle. Below is NOAA’s April 1, 2021 monthly graph, showing the Sun’s sunspot activity through the end of March 2021. I have annotated it as always to show the previous solar cycle predictions.

The higher than expected sunspot activity that has been occurring almost from the moment the ramp up to solar maximum began in 2020 continued in March. The numbers weren’t as high as they were in December and January, but they were still higher than the predicted sunspot number.

March 2021 sunspot activity

The graph above has been modified to show the predictions of the solar science community for the previous solar maximum. The green curves show the community’s two original predictions from April 2007 for the previous maximum, with half the scientists predicting a very strong maximum and half predicting a weak one. The blue curve is their revised May 2009 prediction. The red curve is the new prediction, first posted by NOAA in April 2020.

In last month’s update I said that it was too soon to come to any conclusions about the strength of the next solar maximum, despite these higher numbers. That conclusion still holds, though the longer solar activity continues at these high numbers the more it points to a much more active solar maximum than predicted by NOAA’s panel of solar scientists.

What the Sun is actually demonstrating right now is exactly how little we really know. At the end of the solar minimum a handful of scientists had predicted there would be no upcoming solar maximum at all, based on the previous weak maximum and the two deep and prolonged minimums that surrounded it. That prediction now appears to have been completely wrong.

The solar scientists from NOAA, as indicated by the red curve above, are predicting a relatively weak solar maximum, comparable to the weak maximum seen in 2009. While this prediction, which probably represents the majority opinion of the solar scientist community, is still quite possible, the higher than predicted sunspot activity since the start of 2020 suggests the majority opinion might end up wrong also. Note too that this same majority opinion was wrong about its last solar maximum prediction, as shown by the green and blue curves. First they made two predictions, one high and one low (the green curves). Then they jumped on the bandwagon of the low prediction, after adjusting its time frame to better match the arriving data (the blue curve). And even this last very late prediction ended up too high.

Meanwhile, one solar scientist has predicted a strong upcoming solar maximum, as much as two times stronger than NOAA’s prediction. And though the activity has been higher than the NOAA prediction, it is far less active than this outlier prediction. If activity continues rising at the present pace, this prediction will probably be incorrect also, since the maximum will not be anywhere as active as this high prediction.

All told, what we can gather from these predictions is that they are not based on any real understanding of the underlying processes in the Sun’s magnetic dynamo that causes the solar cycle and the sunspot activity. The scientists are essentially guessing, based on extrapolating past performance. And as every stock broker will tell you, past performance is not always a reliable guide for predicting the future.

This then brings us to climate public policy, which presently tries to tell us that we must make major changes in our lives and our freedoms because some climate scientists have predicted that the Earth is heating up due to human activity. Yet those climate predictions are based on even less certain knowledge than the predictions of the solar cycle, especially because the climate predictions also include these uncertain solar cycle numbers in their models.

Science is always uncertain, though some areas of research are more certain than others. Climate science and the future temperature of our Earth falls more on the uncertain end of the scale, no matter what politicians might tell you. It is not only strongly impacted by the Sun and its cycles, there are many other factors (clouds, pollution, volcanic activity, the atmosphere’s complex make-up) whose long term influence on the global climate remain very unsettled. Any one of these might easily offset the increase in carbon dioxide that we are adding to the atmosphere, especially because even with that increase CO2 remains an atmospheric trace gas, far less influential on the atmosphere’s temperature than water.

Repeat this always, like all good scientists do: We don’t know, we can’t be certain, we must question our conclusions at all times, and the only thing certain about certainty is that it will likely lead us astray.

Genesis cover

On Christmas Eve 1968 three Americans became the first humans to visit another world. What they did to celebrate was unexpected and profound, and will be remembered throughout all human history. Genesis: the Story of Apollo 8, Robert Zimmerman's classic history of humanity's first journey to another world, tells that story, and it is now available as both an ebook and an audiobook, both with a foreword by Valerie Anders and a new introduction by Robert Zimmerman.

The ebook is available everywhere for $5.99 (before discount) at amazon, or direct from my ebook publisher, ebookit. If you buy it from ebookit you don't support the big tech companies and the author gets a bigger cut much sooner.

The audiobook is also available at all these vendors, and is also free with a 30-day trial membership to Audible.

"Not simply about one mission, [Genesis] is also the history of America's quest for the moon... Zimmerman has done a masterful job of tying disparate events together into a solid account of one of America's greatest human triumphs."--San Antonio Express-News


  • Phill O

    Sun spot numbers may be slightly higher than predicted, but numbers alone do not represent the best “picture” of solar activity. This link shows just how different the sun is now compared to earlier activity.

    As to the reference to the CO2 model, one must remember there was no baseline “hard” data for CO2 concentration fluctuations, so we “Really” do not know the ramifications of current apparent fluctuations in carbon dioxide levels.

    Solar influences on the planets remain the greatest one. The tendency for the earth’s buffering capacity to correct small fluctuations in earths climate remains just one of those unknowns. Empirical data remains elusive while imaginary models abound.

    Thanks Bob for the continued reporting on solar activity. This is a long term project quite different from the 1 hour TV programs which solver complex problems in a short time-frame. This is reality!

    As a note for amateur astronomers, the pristine dark skies of the America SW are now very cloudy. This fallows the downward trend I first noted in Alberta skies since 2009 where autumns used to have immaculate skies for viewing. While this empirical data applies to North America, I am wondering if other regions have also observed increased clouds which reduce astronomical views.

  • NavyNuke

    What is interesting to me is to see the divergence in neutron counts at Oulu compared to this same point coming out of the cycle in 2010.

  • wayne

    not directly topical, but very nicely done–>

    “Highlights from SOHO’s 20 Years in Space”
    NASA 2015

  • Star Bird

    Sun Spots have bigger effect on the Weather then do all the SUV’s and Backyard BBQ’s do

  • BG Mendonca

    Until and when scientists can show the physical connection between sun spot numbers and how they are related to the laws of thermodynamics that causes and results in our weather and climate then all they are telling us is about some correlation between sun spot numbers and climate. And we all know that correlation alone without the accompanying laws of physics and thermodynamics is not the cause of weather or climate. .

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