Gerry Pease: It’s all downhill now for solar cycle 24

Posted: December 3, 2014 by tallbloke in Dataset, Solar physics, solar system dynamics

Gerry Pease has sent us a solar cycle 24 update:

It’s all downhill now for solar cycle 24. Cycle 24 Max (smoothed sunspot number 81.9) appears to have occurred in April, 2014:

Cycle 24 progress (last update December 1, 2014

Cycle 23 Solar Max (smoothed sunspot number 120) was in early 2000:

Solar cycles 23-24 (last update December 1, 2014)

Note the progression from cycle 21 to 24:

Graphical comparison of cycles 21, 22, 23 and 24 (last update December 1, 2014)

Similar cycles 12, 14, and 16 had lower peaks than cycle 24, and similar cycles 10, 12, 13, 14, and 16 all had earlier peaks:

Graphical comparison of cycles 10, 12, 13, 14, 16 and 24 (last update December 1, 2014)

Smoothed solar activity since April is projected to be successively lower each month.

Monthly solar cycle data

Month Average solar flux International sunspot number
Smoothed sunspot number Average ap
Measured 1 AU
2013.08 114.6 118.3 66.0 69.0 (+3.5) 8.27
2013.09 102.6 103.7 36.9 73.1 (+4.1) 5.23
2013.10 132.1 131.2 85.6 75.0 (+1.9) 7.71
2013.11 148.3 145.1 77.6 75.4 (+0.4) 5.68
2013.12 147.7 143.1 90.3 76.0 (+0.6) 4.68
2014.01 157.4 152.4 81.8 77.3 (+1.3) 5.44
2014.02 170.3
(cycle peak)
166.3 102.3 (cycle peak) 78.4 (+1.1) 10.70
2014.03 149.9 148.5 91.9 80.8 (+2.4) 4.88
2014.04 143.9 144.8 84.7 81.9 (+1.1)
(likely solar max)
2014.05 129.7 132.9 75.2 80.5 (-1.4) 5.75
2014.06 122.0 125.8 71.0 (79.1 projected, -1.6) 6.72
2014.07 137.4 141.8 72.5 (77.5 projected, -1.6) 4.50
2014.08 124.7 127.9 74.7 (75.1 projected, -3.0) 7.71
2014.09 146.6 148.1 87.6 (71.9 projected, -3.2) 9.78
2014.10 153.4 152.9 60.6 (69.5 projected, -2.4) 8.96
2014.11 154.8 70.1 (67.7 projected, -1.8) 8.9
2014.12 168.1 (1) 5.2 (2A) / 160 (2B) / 91.3 (2C) (66.0 projected, -1.7) (8.0)

It’s going down Jim.

  1. oldbrew says:

    According to the experts ‘Polar field reversals typically occur within a year of sunspot maximum.’
    Cycle 24 has taken about 21 months i.e. nearly twice as long:

    ‘The northern polar field changed polarity first in June 2012, then weakened and was near neutral in March 2014. The southern polar field reversed in July 2013. During the previous similar polarity reversal in 1989-1991 the northern polar field reversed 14 months prior to the southern polar field reversal.’

    Polar field strength graphic from

  2. Slow start to cycle 24. Low peak, depending on how one measures, classifies and averages those things. Might be a few months (perhaps 6) before the spots “collapse”.

    Based on what? You may well ask!

    My earlier fall of dart put the peak at 2014-2015.

    Based purely on visually matching immediately previous, sequential cycles with those from historical records. (David Archibald should take the credit for plotting the historic cycles where I could find them.)

    Better than the Hathaway and Wilson prediction around the same time.

  3. Ian Wilson says:

    Back in late 2007, I made the following prediction for maximum SSN for cycles 24 and 25:

    “The high quality of the correlation in figure 6a can be used to make a prediction of the peak
    annual sunspot number for cycles 24 and 25. If we do this, we obtain 87 ± 11 for the peak annual
    sunspot number of cycle 24 and 72 ± 8 for cycle 25. A peak annual sunspot number of 87 ± 11 for cycle 24 is in good agreement with the predictions of 75 ± 8 made by Svalgaard et al.(2005) based upon the idea that strength of the polar field during the declining phase of one sunspot cycle is a good indicator of the peak sunspot number of the next cycle.”


    Let’s see how well I do with cycle 25.

  4. jeremyp99 says:

    Pale grey on a white background is too hard for my tired old eyes to read easily. What’s wrong with black and white? Books don’t get printed in pale grey and whit, do they? Seems to be the default these days, making blogs unreadable for those with poor eyesight. Whatever happened to accessibility for all?

  5. The met office reporting warmist year ever for CET
    But Antarctic sea ice at a record high with global ice now above average and back to 1979-1989 average.
    No major hurricane for what? 9 years?
    18years of pause
    Our first “turbine power cut” earlier this year in NE Scotland (strenuously denied, but the fingerprint of wind power is there in the power graphs)
    And now a very much diminished sunspot cycle.

  6. Edim says:

    I was skeptical in 2011/12/13 that we were at (or close to) the SC 24 peak and predicted that we have to wait for 2014/15. The cycle is simply very weak and that means long. Now I agree – we are close to the peak (or the plateau maximum, smoothed). The downhill however will be very slow and the next minimum not before ~2022.

  7. tallbloke says:

    Jeremy: sorry, cutnpaste it into a word doc. I had no time to reformat. On way to London now.

  8. Bob Weber says:

    See for today please. Solar activity is fairly evenly distributed across the solar globe at present, as opposed to previous times this year when it was more “lopsided”.

    As the sunspots now are getting closer and closer to the solar equator, where they will eventually peter out, I’m in general agreement here that SC24 is nearly done peaking, however…

    We’ve seen solar F10.7cm flux at a relatively high daily average value for 2014 of 145 sfu/day, 22 sfu/day higher than last year (18% more), 25 sfu/day higher than 2012 (21% more), and 43 sfu/day higher than the daily average F10.7 flux for all of SC24 (42% more). Source:

    For comparison, the last three years of the Modern Maximum in solar activity had average daily solar F10.7cm fluxes of 180, 181, and 180 sfu/day for the years 2000-2002, the solar max years of SC23.

    The major arctic blast we saw in the US several weeks ago (in Nov) was literally melted away by higher solar flux in the second half of November. The first half of Nov we saw the daily flux average 139 sfu; the second half of Nov it averaged 172 sfu/day, and for the whole month the average was 155 sfu.

    For the past nineteen days F10.7 has averaged 170 sfu/day. That is having an impact on the weather, driving temps higher off the tropics, increasing water vapor and precipitation, It’s why California is now finally getting some much needed rain.

    For the next 45 days, the USAF has forecasted F10.7cm flux to average 175 sfu/day, a big bump upwards from previous forecasts of theirs from just a few weeks ago when they had expected activity to diminish. Only one week ago they were calling for it to average 143 sfu/day for the next 45 days from then. Source:

    Disclaimer: the USAF F10.7 forecasts are usually not very good beyond a week, but it’s the only forecast around of its kind. They make a new forecast every day after the official Latest Solar Radio Flux Report from DRAO, Penticton, BC, Canada is made at 20:00 UTC, from It is that measurement which is compiled in NOAA’s daily solar data (DSD) report that I previously cited.

    The Weather Channel yesterday called for 10-15 degrees above average temps for many parts of the US for the next few weeks – how do they know that? I’m sure they also use F10.7 in their forecasting, even though they still preach GHGs drive the climate. I think they know better.

    In other words, we are still experiencing solar max in SC24, which is very closely tracking SC1 right now, and if this cycle mimics SC1 in activity, we could be in for nearly another year of off and on high solar flux driving more solar “warming” during those high flux periods.

    I fully expect temps to head downhill as we get further past the SC24 max into the minimum, as they did during the last minimum, from 2007-2009, until the strong El Nino of 2009-10 kicked temps back up again.

  9. thefordprefect says:

    [mod going off topic somewhat, is there a solar activity wind power linage? — mod]
    Scottish Sceptic says: December 3, 2014 at 10:33 am
    Our first “turbine power cut” earlier this year in NE Scotland (strenuously denied, but the fingerprint of wind power is there in the power graphs)

    I have looked at the plots for 16th April 2014 and there is indeed a sudden drop in demand between 20:35 and 20:40 of less than 3GW – possibly the affected grid being isolated ( more likely a glitch in reporting!). (the time of the reported outage was 20:30 so even these do not match.)

    There is a “sudden” drop in wind of 400MW over 30 minutes from 19:30 to 20:00 “easily” compensated

    20:00 is not 20:35 so they are unlikely to be linked – power has to be matched all the time else the system collapses. So the 400MW loss would have been compensated for by other generators (pumped storage etc.) long before the outage. Plot to follow.

    Perhaps you would care to back up your claim of a fingerprint

  10. vukcevic says:

    I don’t think that the sun’s polar field has hit max as yet, SC24 started later and might be considerably longer than I expected. However as far as the SSN max goes until about a year ago it looked that my estimate (not a prediction or a forecast !) of the non-smoothed SSN oscillating around 80 on the international (SIDC) scale, may have been too high, but although it came later than expected, it appears to be in line with the current events.
    The estimates are based on the ‘formula’ devised in the early 2003 (emailed details to NASA JPL in June 2003, and published in January 2004).
    There were numerous estimates, predictions and forecasts for the SC24 peak before and after the June 2003, but as far as I know the above is the earliest number for the SSN max that currently makes sense.

  11. thefordprefect says:

    I see no windmills!!

    The outage occurred at 2036hrs on Wednesday 16th April, originating from the 275kv
    transmission lines between Blackhillock and Knocknagael and spread quickly north and west
    as network self protection systems sprung in to action to ensure that the electricity

    Over the Easter Weekend SSE investigated further and discovered a faulty electronic relay
    at their Knocknagael Grid Substation near Inverness. It is believed the relay malfunctioned
    just before the outage and sent erroneous information to Blackhillock Substation where
    circuit breakers identified a potential fault on the main network and opened to protect the
    Grid system supplying the north and west of the country. Information from the suspect relay
    has been downloaded and sent to the manufacturer for analysis and comment. SSE have
    reviewed how the relay maloperated and have either switched off the part that was at fault in
    this and other relays or changed their settings. They are confident this will prevent a
    recurrence of the same problem on their wider network.

  12. mkelly says:

    ‘The northern polar field changed polarity first in June 2012, then weakened and was near neutral in March 2014. The southern polar field reversed in July 2013. During the previous similar polarity reversal in 1989-1991 the northern polar field reversed 14 months prior to the southern polar field reversal.’

    I am not understanding how, according to the above, that from June 2012 until July 2013 the Sun had two south poles. A monopole?

  13. tchannon says:

    jeremyp99, I wish there were practical ways to improve Accessibility but compromises and getting wagged by the millstone of youngsters is unavoidable. To a degree you have to do whatever you can yourself. This probably won’t help only explains a little.

  14. Regardless if this is the end of the maximum or not this cycle will be record long in length.

  15. tchannon says:

    mkelly, the way the solar pole is measured can only see one point, at each pole but there is more comprehensive other data, maps.
    The polar field is provided as strength of north and south, of opposite polarity, and the total. The plot shows opposite polarity hence multiple traces. Otherwise the X-axis is by Carrington rotation number. See

  16. Bob Weber says:

    Re: my previous comment

    Penticton F10.7 flux at 20:00 UTC today was 154 sfu, meaning the USAF forecast from yesterday is already off by 11 sfu. They’re making themselves (and me) look bad. I did have to wonder when the eastern solar Earth-facing side is looking nearly blank here – I’m curious as to what old AR2209 is going to look like.

    On the other hand, MAVukcevic’s prediction from eleven years ago is looking very good! Maybe the USAF should consult with him!

  17. oldbrew says:

    SdP : ‘Regardless if this is the end of the maximum or not this cycle will be record long in length’

    Let’s see what happens after the Jupiter-Saturn conjunction in November 2020.

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