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Sunspot update July 2019: Almost no sunspots

Time for my monthly sunspot update. Below is the July graph of sunspot activity released by NOAA yesterday, annotated to give it some context.

July was about as inactive as June, with only two sunspots appearing during the entire month. As with June, one of those sunspots had the polarity for the next solar maximum, signaling once again the beginning of the next cycle.

July 2019 sunspot activity

The graph above has been modified to show the predictions of the solar science community for the previous solar maximum. 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, extended in November 2018 four years into the future.

We have now seen sunspots with a polarity matching the next solar cycle for two months in a row. In every case those sunspots were weak, lasting only a day or so, but they were visible and trackable, more evidence that we will not see a grand minimum in the coming decade. Whether the next cycle will be weak or not remains unknown, though the data suggests it will be weak.

Pioneer cover

From the press release: From the moment he is handed a possibility of making the first alien contact, Saunders Maxwell decides he will do it, even if doing so takes him through hell and back.

Unfortunately, that is exactly where that journey takes him.

The vision that Zimmerman paints of vibrant human colonies on the Moon, Mars, the asteroids, and beyond, indomitably fighting the harsh lifeless environment of space to build new societies, captures perfectly the emerging space race we see today.

He also captures in Pioneer the heart of the human spirit, willing to push forward no matter the odds, no matter the cost. It is that spirit that will make the exploration of the heavens possible, forever, into the never-ending future.

Available everywhere for $3.99 (before discount) at amazon, Barnes & Noble, all ebook vendors, or direct from the ebook publisher, ebookit. And if you buy it from ebookit you don't support the big tech companies and I get a bigger cut much sooner.


  • Dennis Parker

    The text is confusing. Paragraph two seems to be talking about August data as though it already exists. Is this a prediction, or did you mean July data (and presumably June)?

  • Dennis Parker: I have corrected the post. I was talking about data from July and June, not August and July, which is why it made no sense.

    Thank you.

  • Are changes of the geomagnetic field intensity related to changes of the
    tropical Pacific sea-level pressure during the last 50 years?
    Luis Eduardo Antunes Vieira,1 Ligia Alves da Silva,1,2 and Fernando Luı´s Guarnieri3
    Received 22 January 2008; revised 17 March 2008; accepted 9 April 2008; published 26 August 2008.
    [1] The influence of solar variability into the lower atmospheric regions has been
    suggested on different atmospheric parameters in different time scales. However, a
    plausible mechanism to explain these observations remains unclear. Although it is widely
    accepted that the climate change over the past 50 years is attributed to human
    influence, we present the case that local climate change in the tropical Pacific may be due
    to changes in the Earth’s magnetic field strength. The changes in the tropical Pacific
    circulation have been observed during the last 50 years, and they are attributed to the
    increase of the global surface temperature. However, a geomagnetic modulation of the net
    radiative flux in the southern tropical Pacific was recently suggested. Moreover,
    comparisons of long-term reconstructions of the Northern Hemisphere surface temperature
    and solar activity proxies indicated that the existence of a geomagnetic signal in
    climate data would support a direct link between solar variability and their effects on
    climate. Here we show that in the tropical Pacific the sea-level pressure, which is a
    component of the Walker circulation, could be related to the magnetospheric, ionospheric,
    and upper-atmosphere processes which may propagate downward to the lower
    atmosphere. Furthermore, we show that the changes in sea-level pressure and the Walker
    circulation are correlated to the westward drift of the magnetic anomaly. We compare
    the region averaged monthly values of the sea-level pressure in the tropical Pacific with
    those of the magnetic field intensity near the surface for the last 50 years. We find that
    the sea-level pressure in the tropical Pacific is increasing as the magnetic field intensity is
    decreasing. The correlation coefficient of the sea-level pressure 36-month running
    means versus the magnetic field intensity is 0.96. We anticipate our investigation to be a
    starting point for a more sophisticated investigation of the coup

  • John: You put the link to this paper in the “website” box requested when you post a comment. Wrong place, as that only puts the link under your name, and is intended for those who have their own webpage.

    Here is that link [pdf].

  • Phill O

    I am interested in the data from the Maunder and Dalton minima. If we use the same type of equipment, I want to know the correlation of data to today’s instruments.


    Will the old techniques “see” these sun spots, seen with today’s equipment, that are from the next cycle?

    If we look at the trend of the past cycles, one might “guess” that the next cycle will be lower than the last: purely from a logical perspective. Changes tend to be gradual in nature with very few abrupt changes being seen unless “other” events coincide.

  • Raymond A Brooks

    This is the same question I have. There were no satellites in orbit around Earth or the Sun imaging sunspots during the Maunder & Dalton Minima. The sunspot AR2745 July 22 2019 set a record small size of zero-millionths and lasted less than 24 hours. Would that have been counted way back when? If it were not counted then there would have been a 28 day streak of no sunspots lasting till August 5 2019. There seems to be a new tendency in science circles which compares apples to oranges.

  • Phill O

    A review of sun spot detection technology in use during the Maunder and Dalton minima, would be very informative. Reference to specific article for this review would be required. I am tiered of hear-say evidence.

    The apples and oranges question is related to detection limits; verifiable and repeatable detection limits. Yes, and also doing the experiments with that old technology today and comparing to current data available.

    A systematic evaluation of funding going to researchers would also be important to ferret out possible bias.

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