Sunspot update for August 2017


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Yesterday NOAA posted its monthly update of the solar cycle, covering sunspot activity for August. That graph is posted below, with annotations.

August 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 long slow decline to solar minimum has now shown itself. Up until now, the ramp down from solar maximum had been fast and steep, unlike past solar cycles where the ramp down is slow and steady. The last few months the ramp down had practically ceased. In this August graph the ramp down turned into a temporary ramp up. Considering the strong activity going on right now as well as the past week, I expect the September numbers to also show this increase.

None of this means that the ramp down has ended, or that we will not see a solar minimum. All it means is that it takes awhile for the Sun to slowly calm down after each solar maximum. The sunspots we are seeing right now, all near the equator, are from the solar cycle now slowly ending. We will know the minimum is coming as well as the next solar maximum when the first tiny and rare sunspots appear in high latitudes. These high latitude sunspots will belong to the next cycle, and will have reversed polarity.

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2 comments

  • Phill O

    Thanks for the update! Do you have access to the 10cm band data?

  • Phill O

    Looking for the 10.7 cm data, I found NOAA using surface temperature data which is inconsistent with reality. I still can not find historical data like there is for the sun spot number.

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