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Late Sunday NOAA posted its monthly update of the solar cycle, covering sunspot activity for October. As I do every month, I am posting it here with annotations to give it context.
The graph above has been modified to show the predictions of the solar science community. The green curves show the community’s two original predictions 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 sunspot decline continued in October, dropping the sunspot number for the month to below the 2007 low prediction. Though the decline continues to track that low prediction, the sunspot count for November has been even lower, suggesting that the ramp down to solar minimum will continue to under perform that prediction and will arrive at minimum sooner than expected. As I noted last month, this fast decline will also mean that the ending solar cycle will be a both a weak and a short cycle, two phenomenon that in the past never went together. In the past, a short cycle meant the maximum was strong, while a long cycle would correspond with a weak maximum.
The Sun continues to behave in a manner that is unprecedented, and suggests the possibility that a Grand Minimum might be coming.