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NOAA’s monthly update of the solar cycle, covering sunspot activity for November 2018, was released yesterday. As I have done every month since this website began in July 2011, I am posting it below, annotated to give it some 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.
As I have been expecting now for the last three months, NOAA has finally revised this graph to extend it past the end of 2018. The graph below is the graph from October, which follows the layout and design used since 2007. You can see the differences by comparing the two graphs. In extending the new graph to the end of 2022, they fortunately did not change the design significantly. However, because the new graph has a slightly different scale, I have stretched the green and red curves to make them fit properly. While I suspect the poor quality of the 2007 and 2009 predictions is one reason they do not include them on their graph, I think it essential to add them to better understand the limitations of the science.
Solar sunspot activity continues at the same low levels of the past two months, closely matching the level of sunspot activity in 2008 when the last solar minimum began. The extended red curve indicates when they now think the low point of this solar minimum will take place, in late 2021.While this fits with past behavior, whereby the ramp down to solar mimimum is long and gradual, the Sun simply has not been behaving like it has in the past. I would not be surprised if the low point comes sooner, and lasts longer than normal.
Earlier today I posted a link to a prediction of significantly more activity in the next solar cycle. This conflicts with other predictions calling for an even weaker cycle upcoming, some of which say a grand minimum is possible. That the new graph only provides room for sunspot numbers up to 120, compared to the older graph’s 175, suggests that the majority of the community does not agree with today’s prediction, and expects the next cycle to be weak in activity once again.
Nonetheless, like 2007 the solar science community is split, and uncertain about what will happen. This is to be expected, as none of them really understand the magnetic processes in the Sun that cause sunspots and the variations in activity.
Should a grand minimum occur, with no visible sunspots for decades, it will give scientists a wonderful opportunity to gain some deeper understanding of the solar cycle, as we have not experienced a grand minimum since the 1600s, a time before modern astronomy really existed. And if we do experience a strong solar cycle instead, they will then have a new and different clue for figuring out what is going on.