Sunspot update for March 2017

Week Three: Ninth Anniversary Fund-Raising Drive for Behind the Black

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On April 3, while I was in the Grand Canyon, NOAA posted its monthly update of the solar cycle, covering sunspot activity for March. As I have been doing every month since 2010, I am posting it here with annotations to give it context.

March 2017 Solar Cycle graph

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 decline in sunspots continues to run below predictions, suggesting an end to this solar cycle and a solar minimum as early as sometime in 2018. And as I noted in my February update, sunspot activity continues to track the Sun’s 27 day rotation, alternating every two weeks between blank and active hemispheres. We had the longest stretch, more than two weeks, without sunspots in March. This was followed by about two weeks of activity, followed by several blank days and a relatively inactive Sun at present, beginning a little less than a week ago. I expect this period of inactivity to last another ten days or so, and then things will pick up again.



  • mpthompson

    What theories relate our consumption of fossil fuels to such low activity on the Sun? There is obviously some connection because it seems the more CO2 we create, the lower the sunspot activity. This must stop, but obviously Trump isn’t going to do anything about it. ;-)

  • Joe

    Mp, love your comment, the things they blame global warming for……

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