Solar cycle 24 is close to peak

Posted: August 13, 2011 by tchannon in Solar physics

Figure 1

Official version here as gif

I have plotted scaled square root ssn with the Sheet data. This suggests solar cycle 24 is already approaching maximum, the Sheet data nearing 70 degrees tilt.

Why square root ssn?

Many energy processes follow some kind of exponent law, activity is non-linearly dependent on a vector measure of activity. In this case a very rough approximation might be square law, hence square root of ssn is more linear and fits better with a linear internal factor.

Rise times are similar, fall is sharply different cycle 23


Figure 2

This suggests a constancy in risetime but fall varies. Given the slope change 1993, is that a clue on some kind of solar regime change cycle 22? This is where lack of data is hurting. Perhaps history can be reconstructed from other data given we have a rough idea of how one might map to the other.

Comapre with the WSO current sheet visualisation.

Figure 3

Magnetic butterflies


Figure 4


These Hovmoller plots of solar magnetic flux illustrate the solar strangeness in recent years.

WSO have used sine() mapping for the Y-axis to flatten a sphere for viewing.

Equivalent sunspot data seems to be Hathaway’s sunspot area butterfly diagram, from the NASA/Greenwich dataset.


Figure 5

This uses degrees for Y-axis.



Figure 6

Figure 6 is part of a work in progress and should not be taken as exactly accurate.
The comments below the article refer to the polar magnetic cycle, shown in fig 6. Notable is one of the rare close approaches of the solar system barycentre to the centre of the sun itself. This is posited by Wolff and Patrone as leading to excess energy inducement, not the point of discussion here.
Particularly notice the co-incidence of zero crossing of polar field (through zero) with the barycentre closest approach.
A later post may expand on this and much more.

Sunspot data ceases 2008 because I was using an old daily dataset decimated to match the other plots.

There seems to be a contradiction between a rise to somewhere near solar maximum according to the magnetics and the sunspot data.

The shape of sunspot cycles vary, something I looked at in detail a few years ago. What cycle 24 is going to do is a mystery.

All data from Wilcox Solar Observatory, Stanford.

  1. Doug Proctor says:

    If Cycle 24 peaks as described, which looks to be about the beginning of 2012, before 04/2012, does this suggest that the maximum SSN will be about 65, the cycle will be very short, and the following cycle, if also small, look like a Manunder, not Dalton minimum?

    Extrapolations and predictions are difficult, but a) that’s where the fun is, and b) that is where the value is.

  2. tchannon says:

    I’ve only recently been looking at the magnetic data in the context I’ve used. The article was knocked up quickly to provide some new content whilst our host is absent, on top of which I am not a good writer. Not easy guessing what site users want.

    There is more I have not shown, particularly the 22 year magnetic cycle, not quite the same thing. There is a slight problem with that one because I have several what might be more interesting articles based on the data, not ready yet. (sorry about the many uses of not, ugly)

    According to the 22 year it passes through zero polar field around solar max, various plots could be shown. The timing looks likely 2012 however I recently came across a brief paper which offers a fascinating posit suggesting the sun can stay at the same polarity __which may have happened Maunder minimum__.

    They say there were sunspots but were strongly biased to one solar hemisphere. Looking at Hathaway’s plot above, perhaps the cycle around 1880 shows that kind of thing.

    An undulation impressed on various solar data is likely but some data hides that, sunspots a good instance, uni-polar data, whereas underlying is a bipolar signal. I know that is the case from the paired sunspot data: alternate higher-lower sunspot cycles where there is a known bipolar underlying signal. The unevenness is a hallmark of that effect.

    Pointed, rounded, Mohican, etc. the shape is unknown. However, the recent posit that the solar conveyor is sensitive during a short period of a prior solar cycle and will reflect previous values when stuff resurfaces on the next cycle, ought if true allow some kind of guess.

  3. Brian H says:

    My money is on the 50s, based on the time-honoured EW (Eyeball WAG) technology. Also on the belief that the counting of specks as spots will come back and masticate the fundaments of the Sunspot Quantitative Easing Kru (SQEK). It has made the feeble curve of the cycle look stronger than it is, and they will Suffer The Consequences.

    I has spoke. So there!

  4. Tenuc says:

    Thanks for the post Tim, definite sign that something changed around 04/01, and caused the observed ‘step’ that lasted until around 01/04, on the inclination of current sheet plot.

    Some interesting events since then…

    Sudden recent drop in TSI as shown here –

    and here…

    Change to the pattern of the solar mean field from a regular up down spikes to ‘M’ shaped wave form after a flat-lining during 2009.

    Finally we now have a completely ‘spotless’ sun at what is supposed to be solar max.

    I’m enjoying the show, but worried about the consequences of these events.

  5. pennlion says:

    THE QUESTION IS WHAT IS THE CAUSE OR EFFECT If you look at the graph, there seems to be a leading downward hit that triggers the slope change. It is as if a wobble of the solar core, or something, tweaks the properties and then the effect dampens out. If the wobble is strong enough, It would take a long time to dampen out and restore to normal cycles. Bill

  6. Edim says:

    Well, it depends what is close to peak. Do you mean sheet data peak or ssn peak? There’s divergence for sc 24 in your figure 1. The slope of the rise to the peak has bean decreasing. See the comparison for sc 22, 23 and 24 (Leif Svalgaard – Active Region Count):

    I expect long sc 24 (next minimum not before 2021). Maximum probably around 2014.

  7. Roger Andrews says:

    Hi Tim:

    Your figure 2 shows the following solar cycle lengths (eyeballed to the nearest year):

    21: 12 years
    22: 10 years
    23: 14 years

    Mean global temperatures rose during cycles 21 and 22 but flattened out (or at least SST did) during cycle 23. So maybe there really is a relationship between temperature and solar cycle length.

  8. Edim says:


    There is a strong relationship between SCL and temperature. Considering the fact that many other factors affect temperature, the relationship is remarkable. Solar cycle lengths:

    20: (ended 1976.5) 11.6 years
    21: (ended 1986.8) 10.3 years
    22: (ended 1996.8) 10.0 years
    23: (ended 2009.0) 12.2 years


    Click to access 2011_00000005_00000001_74TOASCJ.pdf

    Solar cycles longer than average are associated with cooling and shorter than average with warming. Take into account Earth’s thermal inertia (oceans, sea ice) and almost all temperature variation is explained by SCL. That’s remarkable.

  9. Doug Proctor says:


    Thanks for your reply! You are a clear writer, by the way.

    If we are near solar maximum, but the cycle is long, then previous trends suggest a long, slow decline and flattening before climbing again, which sets up for a low, low period.

    The Dalton Minimum came at a time of cooler temperatures, so what we have to keep in mind, along with Archibald’s ideas, that the “cooling” of a low SSN period is relative to what came before, not a repeat of the temperatures of the 1820s/1830s. A decline of 2 degrees at Hanover, NH is difficult to crosscheck for what would be experienced as a global temperature change. And since, Hanover, NH, is warmer now that it was 100 years ago, once again we wouldn’t experience the temperatures it had during the Dalton Minimum.

    We need to see not just a continuation of the current temperature stall, but a true cooling, over the next four years. By my view, 1998 seemed to have elevated world temperatures above the running trend, so the 2000 – 2010 period is possibly just a return to the long term trend. The variance bar is about reached now – the long-term natural variability of 0.3C or so allows 2010 to be cool relative to the long-term trend without being outside nature. However, even a continuation of the stall will take the trend off-course for a 90% CO2-responsible trend. A decline would be a disaster.

    Me, I’m looking for a moderate decline globally in the next years, enough to derail CO2. About 0.3C. That being said, the natural warming that brought us out of the LIA and lasted until at least 1938 could do anything, positive or negative, since we don’t understand what happened after the 1840s.

    It is so weird that a bunch of smart fellows can tell us precisely how the next 89 years will go but are undisturbed that coming out of the LIA is a mystery.

  10. tchannon says:


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  11. Gerry says:

    Considering what is happening to the Sun right now, I don’t think traditional predictions based on 13 month smoothed sunspot numbers will prove to be at all accurate.

    The monthly SSN peaked last March:

    1995 24.2 29.9 31.1 14.0 14.5 15.6 14.5 14.3 11.8 21.1 9.0 10.0
    1996 11.5 4.4 9.2 4.8 5.5 11.8 8.2 14.4 1.6 0.9 17.9 13.3
    1997 5.7 7.6 8.7 15.5 18.5 12.7 10.4 24.4 51.3 22.8 39.0 41.2
    1998 31.9 40.3 54.8 53.4 56.3 70.7 66.6 92.2 92.9 55.5 74.0 81.9
    1999 62.0 66.3 68.8 63.7 106.4 137.7 113.5 93.7 71.5 116.7 133.2 84.6
    2000 90.1 112.9 138.5 125.5 121.6 125.5 170.1 130.5 109.7 99.4 106.8 104.4
    2001 95.6 80.6 113.5 107.7 96.6 134.0 81.8 106.4 150.7 125.5 106.5 132.2
    2002 114.1 107.4 98.4 120.7 120.8 88.3 99.6 116.4 109.6 97.5 95.0 81.6
    2003 79.5 46.2 61.5 60.0 55.2 77.4 85.0 72.7 48.8 65.6 67.2 47.0
    2004 37.2 46.0 48.9 39.3 41.5 43.2 51.0 40.9 27.7 48.4 43.7 17.9
    2005 31.3 29.2 24.5 24.4 42.6 39.6 39.9 36.4 22.1 8.5 18.0 41.2
    2006 15.4 5.0 10.8 30.2 22.2 13.9 12.2 12.9 14.5 10.4 21.5 13.6
    2007 16.9 10.6 4.8 3.7 11.7 12.0 10.0 6.2 2.4 0.9 1.7 10.1
    2008 3.4 2.1 9.3 2.9 2.9 3.1 0.5 0.5 1.1 2.9 4.1 0.8
    2009 1.5 1.4 0.7 1.2 2.9 2.6 3.5 0.0 4.2 4.6 4.2 10.6
    2010 13.1 18.6 15.4 7.9 8.8 13.5 16.1 19.6 25.2 23.5 21.6 14.5
    2011 19.0 29.4 56.2 54.4 41.6 37.0 43.9

    Examination of the daily NOAA SSN shows that it is unlikely that the August SSN will be as high as the March or April SSN. Note also that Leif was apparently correct in diagnosing the dramatic drop in TSI as being due to the very large sunspots earlier. TSI is back up:

    The Sun is now spotless. The last time this happened, according to NOAA, was January 27, 2011:

    We can all agree that it will be very interesting to see how long (or short) the current spotlessness will continue, and just how many spots will again appear when spotlessness ends. Will there be a later monthly burst of high activity peaking higher than in March? It’s still very much a guessing game, but it looks to me like the Sun may be already entering another prolonged Minimum.

    –Gerry Pease

  12. Gerry says:

    I no sooner wrote my comment above than my question about duration of spotlessness was answered. Just one day at present. A spot has just rotated into view:

  13. bill says:

    Great post as usual Tim. SC24 is likely to be a bit “wonky” since we are due for a “sign change” re your post of Aug 02. It is possible that we could move directly into SC25 without a solar magnetic “reversal”.

    Have you tried plotting sunspot latitudes and solar magnetic “equator” against the plots in this post?

    For those interested in earth’s reaction – All parameters are changed and changing – our reaction will not be the exact same as during similar minimums. Our current minimum is following SC5 quite closely. See LAYMAN’S SUNSPOT COUNT. Our current Bond/Heinrich/D-O timing is due to “ripen” in ~ 2160 at which time the sun’s center has a similar “close approach” of the SSBC. Stay tuned.

  14. tallbloke says:

    Hi Tim,
    great post, thanks. Regarding your comment on Wolff and Patrone:

    “Notable is one of the rare close approaches of the solar system barycentre to the centre of the sun itself. This is posited by Wolff and Patrone as leading to excess energy inducement”

    I appreciate this isn’t the point of the discussion but I feel the need to expand on your statement.
    The Wolff and Patrone effect operates differently at different solar radii. They say (speculatively) that some helioseismic evidence of a discontinuity at R=0.15 may be consonant with the W&P effect operating at that radius when the Barycenter passes close to the solar centre. The posit that the effect may “carry fresh fuel to deeper levels”, and that this means that “stars with planets orbiting will burn a little more brightly and have shorter lifetimes”. But this would be a diffuse effect, because of the timescales involved (many thousands of years), for energy tp percolate from the solar core to the boundary of the radiative and convective zones around R=0.65. It is in the latter that the effect would be expected to manifest on timescales of a rotation or two, thus contributing to solar variation on solar cycle and sub cycle frequencies.


  15. P.G. Sharrow says:

    Has anyone noted the appearant contridiction of lower TSI during periods of high sunspot activity and warming of the earth to the idea that higher TSI equals more total output. A “quiet” sun means higher TSI and global cooling?
    There is a lot more to solar output then TSI. pg

  16. tchannon says:

    There is some disagreement between Rog and myself over W&P.

    As Rog says W&P are talking about a deep solar effect which takes some unknown time to do something. The assumption is the sun has a structure where they are suggesting a pull of new fuel to shallower layers over a couple of solar cycles and leads to increased fuel for “burn”.
    I think Rog is concerned I am too closely linking any of that with a more immediate minor effect I suspect is there. Please correct if any of that is wrong.

    This is not the right time to say a lot.

    The point of figure 6 above is barycentre “zero” and magnetic zero are together. This is information to be filed away in mind for when a new jigsaw piece presents itself.

    Barycentre events like that seem to be randomly phased relative to the sunspot cycle, whereas magnetic zero is near sunspot solar maximum. However this might turn out to be completely wrong, perhaps even key.

  17. tallbloke says:

    PG, Leif Svalgaard changes his story to suit the moment on this. Two years ago he was saying the cool areas were compensated for by an increase in apparent diameter of the Sun at solar cycle peak.

    I suspect there is no simple relationship between zero crossings in the x-y plane and solar magnetics. There is inertia in the system and other factors to consider, including the z-axis situation IMO.

  18. tchannon says:


    One view seems to be UV etc. increases, all gets rather complicated. TSI is not total, certainly not total energy coupling, nor is the figure known as accurately as often assumed.

    Lets put some of this into context

  19. bill says:

    We seem to have deviated a bit from Tim’s reason for this post, which I assumed was to show the correlation between Solar cycles and the Heliospheric current sheet. Basically – giving an indicator of the expectancy time of solar Maximum among other things.

    For perturbed cycles/affected cycles, see

    Figure 1 shows perturbed cycles and affected cycles

    Figure 2 Shows BC depiction of the suns center in relation to the BC – Note that in 1990 the sun’s center passed the BC moving counter clockwise instead of its usual passing in a clockwise direction.

    Figure 6 is followed by a description of things (including timing) which control the effect of perturbations, (from severe to non existing)

    TSI measurements are in a developing stage. The Effect of EUV was originally omitted because “it was filtered out by our upper atmosphere” . It is now realized that the warmth – or lack thereof – in the upper atmosphere plays a large part in determining surface temps. Getting the effect of EUV (and probably a few other things) taken into reasonable accounting will take time.

  20. Ulric Lyons says:

    The graph: suggest SC24 maximum late 2013 to early 2014.

  21. […] See earlier on Tallbloke’s Solar cycle 24 is close to peak […]