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Late last night NOAA released its monthly update of the Sun’s sunspot cycle, covering the period of March 2013. As I have done every month for the past three years, I am posting this latest graph, with annotations to give it context, below the fold.
While the Sun’s output of sunspots increased in March, it did not do so with much vigor, with the numbers still far below all predictions while also showing an overall decline since a single strong peak in October 2011.
For reference, the green curves in the graph show the two original predictions of the solar scientist community from April 2007, with half the scientists predicting a very strong maximum and half predicting a weak one. The red curve is their revised May 2009 prediction.
The slight increase last month allowed the scientists at the Marshall Space Flight center to keep their prediction unchanged for the solar maximum, only the second time in eight months they have not revised and lowered their prediction. As I noted last month, since January 2012 these scientists have changed their prediction 20 times, with numbers ranging from 59 to 99. These numerous changes and their wide range so close to the actual maximum illustrates quite clearly how little they really know about the sunspot cycle and how much they are actually guessing.
The Sun could still wake up. The solar scientist community is still calling for a second peak to occur this coming fall, resulting in a double-peaked maximum. As far as I can tell, however, the only evidence they have to justify this prediction of a second peak is that in past maximums the Sun has sometimes produced a double peak. They might be right, but to my mind this isn’t science but wild-eyed gambling, no different really than predicting that, just because someone else once won the lottery in the past, I might win it too!
Either way, the solar maximum will soon be over, and we will begin the steady ramp down to solar minimum and to no sunspots. The question then will be this: Will the solar cycle shut down, as it did in the 1600s, and produce another Grand Minimum lasting decades, as some solar scientists are predicting? Or will sunspots come back, and the Sun return to its days of high activity as seen through most of the 19th and 20th centuries?
Stay tuned, buckos, since an inactive Sun has also been accompanied by cold global temperatures. If the sunspot cycle shuts down, you might need that heavy winter coat, even if you live in a presently warm climate!