What Are The Experts Predicting For Solar Cycle 25?

The  Global Warming Policy Forum on 15 May 2020 posted   “The Sun Has Entered “Very Deep” Solar Minimum” /authored by David Whitehouse.    It provided a list of predictions of SC 25’s maximum sunspots.   I have rearranged the chart to show the predictions that suggest it will be less active than SC 24, those that expect SC24 and SC25 to be nearly identical and those that predict it will more active.

As a benchmark, SC 24 sunspots at maximum were 116.4

       Less Active

Labonville 89+29/ -14
Ahluwalia 7
Singh 89+/-9
NASA 58 to 81 (30% to 50% less than SC24)


          Nearly Identical Activity

Pishkalo 116+/-2
Komitov Same or slightly larger
Bhrowmik Same or slightly larger
NOAA 95 to 130


   More Active

Miao 121+/-32.9
Svalgaard 116.4 to 156.6
Han 228+/-40.5
Li 168+/-6.3
Dani 159+/-22.3

Leif Svalgaard was the most accurate predictor of SC 24.  His method has been widely adopted by other predictors.   See my posting Predicting Solar Cycle 25 for a description of his method. By my reading all of the “nearly identical” used his system.  Oddly, Svalgaard did too but his range is pretty wide, suggesting something, perhaps that he is not as confident in its use as are his copiers.   Miao used OHL precursor method—I am not sure what that entails.  Han used Vondrack smoothing of multiple SCs to get his prediction.  Li used Data Analytics for his.  Dani used 4 different machine learning regression method for his.   Labonville used Joy’s law, and here again I am not familiar with that. Bhrowmik used a version of the Svalgaard method.

Ahluwalia is the boldest prediction of them all.  He concluded that 7 will be the maximum sunspot sighting for SC 25.  His number is based on the Livingston and Penn prediction that SC25 will have very  few sunspots.  For many years they have recorded sunspot magnetic field strength and they say it is declining.  They forecast that the sunspots will largely disappear when their magnetic field strength is no longer strong enough to overcome the solar sun field strength.        See this Posting Cheshire Cat Sunspots for gain a better understanding.

It interesting to see that the two government bodies came up with quite different analysis.  NASA was way off last time around.  They predicted about double the actual SC 24 result. So, it looks like this time they are going low this time.    And this is a quote from their posting on their prediction:

“The forecast for the next solar cycle says it will be the weakest of the last 200 years. The maximum of this next cycle – measured in terms of sunspot number, a standard measure of solar activity level – could be 30 to 50% lower than the most recent one. The results show that the next cycle will start in 2020 and reach its maximum in 2025.”

NOAA on the other hand said that it will be weak, but it breaks the trend of weakening solar activity seen over the past four cycles.  They add that there is no indication that we are currently approaching a Maunder type minimum in solar activity.



Predictor’s affiliation and in some cases, methods can be viewed in the posting sited above for the source of the tables.

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s