Solar scientists struggle to predict the next sunspot cycle

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Link here. This is a detailed article describing the meeting in March where the solar science community gathered to formulate its prediction for the next solar cycle.

What stands out about the meeting is the outright uncertainty the scientists have about any prediction they might make. It is very clear that they recognize that all their predictions, both in the past and now, are not based on any actual understanding the Sun’s magnetic processes that form sunspots and cause its activity cycles, but on superficial statistics and using the past visual behavior of the Sun to predict its future behavior.

“There’s not very much physics involved,” concedes panelist Rachel Howe of the University of Birmingham in the United Kingdom, who has been tasked with reviewing the mishmash of statistical models. “There’s not very much statistical sophistication either.”

Panelist Andrés Muñoz-Jaramillo of the Southwest Research Institute in Boulder agrees with Howe. “There is no connection whatsoever to solar physics,” he says in frustration. McIntosh, who by now has walked downstairs from his office and appears in the doorway, is blunter. “You’re trying to get rid of numerology?” he says, smirking.

The result, as I repeatedly note in my monthly sunspot updates, is that the last prediction failed, and that there is now great disagreement among these scientists about what will happen in the upcoming cycle.

[They] dutifully tabulate the estimates, and come up with a peak sunspot range: 95 to 130. This spells a weak cycle, but not notably so, and it’s marginally stronger than the past cycle. [They do] the same with the votes for the timing of minimum. The consensus is that it will come sometime between July 2019 and September 2020. Maximum will follow sometime between 2023 and 2026.

The range of predictions here is so great that essentially it shows that there really is no consensus on what will happen, which also explains why the prediction has still not been added to NOAA’s monthly sunspot graph. For past cycles the Sun’s behavior was relatively consistent and reliable, making such statistical and superficial predictions reasonably successful.

The situation now is more elusive. For the past dozen or so years the Sun has not been behaving in a consistent or reliable manner. Thus, the next cycle might be stronger, it could be weak, or we might be heading into a grand minimum, with no sunspots for many decades. These scientists simply do not know, and without a proper understanding of the Sun’s dynamo and magnetic field, they cannot make a sunspot prediction that anyone can trust.

And so they wait and watch, as we all. The Sun will do what the Sun wants to do, and only from this we will maybe be able to finally begin to glean an understanding of why.



  • BSJ

    Is a Grand minimum truly “no sunspots for decades” or just very few over that time frame?

  • Jay

    There are few. There have been other minimums and sunspots do appear, just not a lot.

  • BSJ: It is no visible sunspots for decades. With today’s instrumentation, we will certainly detect evidence of faint sunspots during the next grand minimum, but they will be very faint and rare.

    During the last grand minimum in the 1600s no sunspots were recorded, but recent research has culled out evidence that a few faint spots had occurred, but were undetectable at the time.

  • Phil Berardelli

    I think it’s likely that present-day instruments will be much more capable of detecting the smallest sunspots, whereas during the Maunder Minimum the telescopes were, to put it mildly, crude. This adds to Bob’s main point that solar science contains a great deal of uncertainty. We might indeed be heading into another grand minimum, and if so it should contribute greatly to our knowledge of solar physics. All we can do for the time being is watch, wait and interpolate the data as it arrives.

    A bit less certain and more suspenseful than when I wrote about the phenomenon nearly a decade ago:

  • This article from a couple years ago reinvigorates an old notion. I found it quite intriguing.

    Suppose every 11 or so years the a chaotic system in the sun is provoked by the current planetary alignment, and the solar cycle is set in motion until the next quiet period, when a new stimulus by the planets weighs in. Meaning each cycle is a stand-alone phenomenon, and the dice are thrown every 11 years to determine the general character of the next. Several flat cycles in a row is happenstance. The consequences, as Bob often suggests, are still just as real.

  • wodun

    We don’t understand the sun, but we totally understand the Earth’s climate. It is rather refreshing to see scientists express uncertainty, to have the ability to express it without fear of being unpersoned.

  • Jay

    I look at the solar data daily. When it comes to radio propagation I use those numbers like a thermometer and barometer: mainly the K index (solar storms) and the SN (Solar Flux).
    One source I use to help predict what is coming is Tamitha’s weekly predictions: Just like watching the weatherman on television.

  • Edward

    wodun wrote: “We don’t understand the sun, but we totally understand the Earth’s climate. It is rather refreshing to see scientists express uncertainty, to have the ability to express it without fear of being unpersoned.

    Science thrives on uncertainty. Science’s objective is to become more certain about the world and universe around us. It is when we are fairly certain about a topic that we start working on explaining the nuances of the science. For example, we are exploring the ideas of dark matter and dark energy in order to explain two unexpected nuances in celestial mechanics.

    When the science is settled, however, then it is time to stop funding further research in order to concentrate on other scientific areas, those that still have uncertainty or where the nuances need explanation.

    Hmm. Could someone please explain again (I keep forgetting) why we still fund climate science even though the science is settled, the consensus agrees, all debate is over, and there are calls for skeptics to be shunned, banned, re-educated, imprisoned, or executed?

    I’m so glad that there are still scientific areas that still have some uncertainty, unlike climate science.

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