Solar cycle 4b, support from 10BE proxy

Posted: February 28, 2015 by tchannon in Solar physics

One of the unsolved solar mysteries is the peculiar behaviour around year 1800. The data we have is poor leading to ambiguity on whether a solar sunspot cycle is missing from the record.


Figures from paper. For a legible copy you will need to register and download the PDF.

The lost sunspot cycle: New support from 10Be measurements
C. Karoff, F. Inceoglu, M. F. Knudsen, J. Olsen, A. Fogtmann-Schulz
A&A 575 A77 (2015)
(early preview with registration)


It has been suggested that the shortage in the number of spots on the surface of the Sun between 1790 and 1830, known as the Dalton minimum, contained an extra cycle that was not identified in the original sunspot record by Wolf. Though this cycle was shorter and weaker than the average solar cycle, it shifted the magnetic parity of the solar magnetic field of the earlier cycles. This extra cycle is sometimes referred to as the “lost solar cycle” or “cycle 4b”. Here we reanalyse 10 Be measurements with annual resolution from the North Greenland Ice Core Project in order to investigate if the hypothesis regarding a lost sunspot cycle is supported by these measurements. Specifically, we make use of the fact that the Galactic cosmic rays, responsible for forming 10 Be in the Earth’s atmosphere, are affected differently by the open solar magnetic field during even and odd solar cycles. This enables us to evaluate if the numbering of cycles earlier than cycle 5 is correct. For the evaluation, we use Bayesian analysis, which reveals that the lost sunspot cycle hypothesis is likely to be correct. We also discuss whether this cycle 4b is a real cycle or a phase catastrophe, and what implications this has for our understanding of stellar activity cycles in general.

The authors are cautious. They’ve used Bayesian methods to push hard on the limits of what can be done.

They claim no more than the supposition is supported but do not rule out other explanations.

corresponding to a p-value of 99.82 ± 0.06%, which implies that the lost cycle hypothesis is decisively supported by the 10 Be measurements from the NGRIP ice core.

Though we have shown that the lost cycle hypothesis is decisively supported by the 10Be measurements, there are still a number of explanations that cannot be ruled out.

And go on to discuss some of them.

Post by Tim

  1. tallbloke says:

    Thanks Tim, very interesting. I suspect we may see some kind of ‘phase catastrophe’ becoming evident in the data over the next 10 years too. I expect some wild weather on Earth as a result. This will of course be atributed to a 0.04% trace gas in the atmosphere rather than odd behaviour in the feckin’ great nuclear fusion reactor we orbit around.

  2. vukcevic says:

    I looked into this some 4 or 5 years ago, had number of exchanges with Dr.S.
    When the ‘sunspot formula’ is plotted in its logarithmic form (adding nominal value of 1, to avoid 0 counts) it clearly shows lost sunspot cycle, here labelled as SC4a.

    Similar effect is expected 2028-2032

  3. c777 says:

    There’s a weaker peak around about 2010 looks like its headed South.

    I suppose the Thames freezing over in Winter will be termed as a man made extreme weather event, though trying to sell intermittent power to a struggling economy is going to be a hard sell.

  4. The paper is here:

    Many papers can be accessed via Google Scholar.

    Look for

    “Related articles – All 2 versions – Cite – Save”

    and click All 2 versions. Better than 50% success rate.

  5. Re Vukcevik post and reference to Feyman and Gabriel (1990)

    Period and phase of the 88-year solar cycle and the Maunder minimum – Evidence for a chaotic sun

    The paper is here:

    courtesy of Google Scholar.

  6. ren says:

    Nature 399, 437-439 (3 June 1999) | doi:10.1038/20867; Received 21 December 1998; Accepted 12 April 1999
    “The solar wind is an extended ionized gas of very high electrical conductivity, and therefore drags some magnetic flux out of the Sun to fill the heliosphere with a weak interplanetary magnetic field1,2. Magnetic reconnection—the merging of oppositely directed magnetic fields—between the interplanetary field and the Earth’s magnetic field allows energy from the solar wind to enter the near-Earth environment. The Sun’s properties, such as its luminosity, are related to its magnetic field, although the connections are still not well understood3,4. Moreover, changes in the heliospheric magnetic field have been linked with changes in total cloud cover over the Earth, which may influence global climate5. Here we show that measurements of the near-Earth interplanetary magnetic field reveal that the total magnetic flux leaving the Sun has risen by a factor of 1.4 since 1964: surrogate measurements of the interplanetary magnetic field indicate that the increase since 1901 has been by a factor of 2.3. This increase may be related to chaotic changes in the dynamo that generates the solar magnetic field. We do not yet know quantitatively how such changes will influence the global environment.”

  7. ren says:

    Figure 3 The total solar magnetic flux emanating through the coronal source
    sphere12, Fs. Shown are the values derived from the geomagnetic aa data for
    1868–1996 (black line bounding grey shading) and the values from the interplanetary
    observations for 1964–96 (thick blue line). The variation of the annual
    means of the sunspot number hRi is shown by the area shaded purple and varies
    between 0 and a peak of 190 for solar cycle 19.

  8. ren says:

    “The most striking feature of the Sun’s magnetic field is its cyclic
    behaviour. The number of sunspots, which are dark regions of
    strong magnetic field on the Sun’s surface, varies with a period of
    about 11 years. Superposed on this cycle are secular changes that
    occur on timescales of centuries and events like the Maunder
    minimum in the second half of the seventeenth century, when
    there were very few sunspots1,2. A part of the Sun’s magnetic field
    reaches out from the surface into interplanetary space, and it was
    recently discovered3 that the average strength of this interplanetary
    ®eld has doubled in the past 100 years. There has hitherto been
    no clear explanation for this doubling. Here we present a model
    describing the long-term evolution of the Sun’s large-scale magnetic
    field, which reproduces the doubling of the interplanetary
    field. The model indicates that there is a direct connection
    between the length of the sunspot cycle and the secular variations.”

  9. oldbrew says:

    A bit OT but there’s a partial solar eclipse due over the UK on March 20th – up to 98% in northern Scotland. Parts of the Faroe Islands should get the full monty.

    ‘The National Grid has warned that solar power output in Britain will halve during the event.’ 😉

  10. vukcevic says:

    there is a “major” (official classification) geomagnetic storm under way.


  11. vukcevic says:

    Something odd there, current image is replaced by out of date. To get correct one click on the one displayed
    [fixed, Tim]

  12. Sparks says:

    Leif Svalgaard told me once that sunspot numbers are higher in some records for solar cycle 5.. I don’t like things that match up around that period, any orbital and 10be data I’ve looked at seems to point towards and confirm that solar cycle 5 was much higher and solar cycle 6 was the unusually low cycle.. just a thought!

  13. Ren, I like the chart you sent at 8:15am march 01

  14. Geoff Sharp says:

    I am in the phase catastrophe camp of which we are seeing at present when looking at the solar polar field strength graph. Interestingly around 1790 the sun changed its orbit around the SSB as a result of the particular lineup of the 4 outer planets, the solar orbit paths are not linked to the solar cycle itself, so timing is of immense importance.

    So during the downslope of SC4 the Sun alters its path which could have altered the normal dynamo action and caused a resurgence of solar activity at the tale end of SC4. A phase catastrophe results at the poles which then breaks the Hale cycle which then takes one of two cycles to rebuild.

    So there are two factors that can affect solar output because of the disordered orbit (10 year orbit). The dynamo is changed depending on the timing of the orbit in relation to the solar cycle, and the poles go into a phase catastrophe state that affects the dynamo in a secondary manner for cycles following. SC24 is different as the irregular orbit is occurring on the beginning phase of the solar cycle, so there is direct disruption to the dynamo in real time as we have seen. But the solar pole strength is also likely to go quadrupole or at least hang around neutral which should be the dampening force for at least SC25.

    This diagram has all the detail. It shows the orbit shapes in relation to cycle timing and how we can quantify the orbit shape along with the perturbation of angular momentum etc.

  15. Sparks says:

    What is this ‘phase catastrophe’ is it a term for the slowing down of the polar fields?, because all I can see happening is the polar field reversals are slowing down and producing less sunspots. the polar fields also speed up and produce more sunspots, the sine-wave in the graph above called ‘angular momentum curve’ is identical to the speed the of the polar field reversals, and it’s very interesting that the timing of the distance between Uranus and Neptune have the exact same rate of orbital change.. I mean the correlation is absolutely staggering!

  16. Geoff Sharp says:

    Hi Sparks, glad to see someone paying attention 🙂

    The “phase catastrophe” I refer to is the breakdown of the Hale cycle where one or both poles fail to change polarity near cycle max, which probably is a result of not enough reversing flux traveling to the pole during a severally reduced dynamo.

    When you say polar reversal speed I assume you mean solar cycle length, which correlates with weaker cycles being longer. In general stronger/shorter cycles occur during times of high AM but grand minimum type cycles also occur near the top of the wave. The top of the wave is always U/N together. I calculated the wave by inverting the AM values below the centre of Carl Smiths AM graph, history shows us it is the amount of movement in any direction on the AM graph that produces the largest cycles, by inverting all values under the centre point we see the true AM strength (purple peaks)

  17. linneamogren says:


    “I suspect we may see some kind of ‘phase catastrophe’ becoming evident in the data over the next 10 years too. I expect some wild weather on Earth as a result. This will of course be atributed to a 0.04% trace gas in the atmosphere rather than odd behaviour in the feckin’ great nuclear fusion reactor we orbit around.”

    I always thought it amazing if you mention the Sun as a major influence on temps you are looked at these days as some witch burner from Salem. So, C02 has a greater impact than the Suns solar irradiance ( which is underplayed by NASA ) value of ,[1] 1.3608 +/-0.0005 kW/m², which is 81.65 kJ/m² per minute? I can’t accept that…….

    There seems to be a strong correlation with the length of the solar cycle, between years of the highest numbers of sunspots. The temperature anomaly was – 0.4 K in 1890 when the cycle was 11.7 years, but + 0.25 K in 1989 when the cycle was 9.8 years. So lower temps during periods when sunspot activity is at its longest and slowest. Maunder found that during this cold period between 1645-1715 there was very little sunspot activity. Now, with increased temps in the last century the claim is the Suns activity can’t account for the warming witnessed. Really? The average global temperature has increased 0.8°C (1.4°F) since 1880. Only C02 had that ability? Seems like rubbish to me. Oceans can easily make up the difference during periods of low sun activity since they would have been warmed by its more active period and slowly released.

  18. linneamogren says:

    ” While government science and media begin the ramp-up to claim 2014 as the “hottest year ever” China’s Sea’s biggest bivalve shows that the Middle Ages were warmer than today, when Carbon Dioxide was lower. “

  19. tallbloke says:

    Good analysis Linnea. The integration of solar energy in the oceans holds the key to understanding how the Sun was responsible for the late C20th warming even though the max amplitudes of the cycles diminished slowly after 1960. If you integrate the sunspot number by subtracting the long term average of 40SSN from the monthly values, and then make a running total, it shows there was net input to the oceans all the way from 1934 to 2003.

  20. Geoff, this make much sense. Thanks for your analysis.

  21. oldbrew says:

    ‘A solar cycle lost in 1793-1800: Early sunspot observations resolve the old mystery’

    ‘Using the newly recovered solar drawings by the 18-19th century observers Staudacher and Hamilton, we construct the solar butterfly diagram, i.e. the latitudinal distribution of sunspots in the 1790’s. The sudden, systematic occurrence of sunspots at high solar latitudes in 1793-1796 unambiguously shows that a new cycle started in 1793, which was lost in traditional Wolf’s sunspot series.’

  22. tchannon says:

    You might have found a paper I came across, think there are several on this topic, and couldn’t find in the archive here.

    If this odd solar behaviour it real I wonder whether there are multiple interacting processes going on. It also fits with the stange behaviour during the latter part of cycle 23 even though with far better data nothing was clear.

    Turning to the current (marked Jan 2014) page

    For cycle 24 this writes ” Many cycles are double peaked but this is the first in which the second peak in sunspot number was larger than the first.”. This might be further clues on multiple processes.

  23. oldbrew says:

    Cycle 16 looks like a second-larger-than-first peak?