Sunspot update: Sunspot activity fell in July, indicating a return to ramp down
Below is my monthly graph of the Sun’s sunspot activity in the past month, based on NOAA’s graph showing the sunspot activity on the Earth-facing hemisphere but annotated further by me to make clear the larger scientific context.
In July sunspot activity declined from the previous month, dropping to the lowest level since the peak in September 2024, as shown by the green dot in the graph. That drop suggests that the six-month pause in ramp down to solar minimum has ended, and that the Sun will not experience a second peak, as it did in the previous two solar maximums.
Or not. The decline did not go significantly lower than the previously lows, and could equally be interpreted as just an additional month in that pause. We will only know, one way or the other, in the coming months. Predictions of solar activity have routinely failed during the past two solar cycles, as shown on the map below.
The graph above has been modified to show the predictions of the solar science community for both the previous solar maximum as well as the ongoing maximum. The green curves show the community’s two original predictions from April 2007 for the previous maximum, with half the scientists predicting a very strong maximum and half predicting a weak one. The blue curve is their revised May 2009 prediction. The red curve is the new prediction, first posted by NOAA in April 2020. At the beginning of April 2025 NOAA’s panel of solar scientists added the purple/magenta curve line, predicting that solar maximum was over, and that the ramp down to minimum had begun.
There is not much more to say that I haven’t said for the past sixteen years in practically every sunspot update each month. The solar science community does not really understand the fundamentals that cause this cycle, base all their predictions on past superficial behavior that does not guarantee future results. Thus, those predictions are routinely off.
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When does anecdotal evidence become empirical data?
We have been living in Sacramento, CA* for decades. Years ago I started noticing an after-the-fact correlation between the Sunspot report and the daily temperatures. Yes, it hot in the summer. Sometimes in the winter there are overnight freeze warnings. What I have noticed, in both winter and summer, is when there is a significant drop in temperature, for more than a few days, the next sunspot report will be less sunspots. It happens over and over.
*CA – yes we live in California. We are part of a huuuuuge Irish Catholic family, or we would have relocated. We enjoyed Ronald Reagan as Governor, fighting the good fight with S. I. Hayakawa. We enjoyed Rush when he started in Sacramento, 1984. Those were the days.
There are still many pockets of sanity, but we do not count the votes.
Ronaldus Magnus,
You asked: When does anecdotal evidence become empirical data?”
Anecdotal evidence is more self selected than scientifically collected. Empirical data is somewhat more scientific than hearsay.
In the book The Martian, one character asks what were the chances that an astronaut would be left behind on Mars. Another character says that the empirical data shows one in three. He was using observations from all the missions flown so far, which is what made it empirical rather than anecdotal. Anecdotal would be mentioning that an astronaut was once left behind, but that leaves out context, such as the total number of missions and the total number of astronauts left behind.
Unfortunately, your evidence will not become empirical data, because you don’t have the same kind of context, just an observation that sometimes it happened and that you noticed a pattern that happened over and over, but was it every time or did you only notice the times that it happened? How much did the temperature drop and for how many days?
One of the features of the hypothesis about the sun spots relating to the Earth’s overall temperature is that it is a long-term, decades-long phenomenon, not monthly. The hypothesis has to do with global temperatures, not Central Valley temperatures. The thinking behind the hypothesis is that during times of solar activity, the Sun’s magnetic field reduces the number of cosmic rays that reach the Earth. The cosmic rays result in a fractional amount of additional cloud formation, less sunlight reaches the surface, and a cooling of the planet, according to this hypothesis, so when there are fewer sunspots, then the Earth has more clouds and cools over decades. More sunspots reduces the number of clouds and the Earth warms.
This is not a short-term phenomenon, because we do not see cooling/warming trends during the eleven year cycle. This lack of short-term thermal response does not negate the hypothesis, but it does not support it, either. The hypothesis needs more Maunder minimums or Dalton minimums to help determine its validity. Right now, the mini-ice ages associated (correlated) with these minimums may just be coincidence, or they could be causal, and we cannot know for decades, even if we are approaching a similar minimum now. Comparing all the sunspot cycles to all the long-term temperature trends is what makes this empirical evidence rather than anecdotal.
The correlation of temperature drops coincident with these two minimums is closer to anecdotal evidence than empirical, but as we collect more data about the two phenomena and can determine their relationship (or lack thereof) to each other, the more empirical it becomes, because we now have reason to watch closely. The Little Ice Age was not well documented in an empirical fashion (no empirical thermometers), unlike the lack of sunspots that we related to it.
I have seen correlations of cycle length to overall temperature changes as well as the height of the peaks of the numbers of sunspots. These may be significant correlations — or maybe not.
If we had had data during the medieval warm period, it would add more to our sun’s story.
The sun must’ve heard you talking, it has your attention…
https://spaceweather.com/m/
It will hit us on the seventh.
Any pictures of the booster hitting the moon yet?