More on the Maunder Minimum


A few months back, I wrote a bit about the solar cycle and its problems. Here is some more info on this, which is now becoming a worrying problem.



Above is a Morlet continous wave transformation for sunspots . Another can be seen here
Time is read along the horizontal axis, and a time scale is drawn across the top of the image. Frequency is read on the verticle axis. The scale is 2**x months, where is is 1,2,3..9. So 2**7 is 128 months. Amplitude is indicated by color. The basic 11 year Schwabe cycle is clearly indicated by the red ovals bisected by the line for 11 years. I’ve noted the Dalton Minimum, which is clearly different in character than the other cycles — with weaker and longer solar cycles. It is subtle, but you can see the weaker intensity of solar cycles 10-15 compared to solar cycles 16-23 in the weaker color of the earlier cycles. There is clearly enhanced activity, and of longer duration, at the end of the 20th century.
There is also a weaker, but distinct, level of activity at 22 years, the double sunspot of Hale cycle. The last three Hale cycles have been stronger than earlier Hale cycles. There is some indication of a double Hale cycle (~44 years) and at the top of the graph, we’re in Gleissberg cycle territory.
Now, for an interesting observation and speculation, note that at present, which is at the right edge of the chart, from the 11 yr line to the top it is all blue. There is only one other place on the entire chart where we can draw a vertical line from the 11 yr line to the top without it crossing some portion of color other than blue. Can you find it? (It is right at the beginning of Solar Cycle 5, i.e. the Dalton Minimum). Are we watching the beginning of a new 200 year cycle like what began with the Dalton Minimum in the early 1800’s? Obviously, no one knows. But the current transition is certainly unusual, and invites comparison to past transitions.

This is a Morlet continous wave transformation for sunspots for the last
11405 years.
This is the data set used to produce the wavelet.
Solanki, S.K., I.G. Usoskin, B. Kromer, M. Schüssler and J. Beer. 2004. An unusually active Sun during recent decades compared to the previous 11,000 years. Nature, Vol. 431, No. 7012, pp.1084-1087, 28 October 2004.

The diagram above is for the data set here

This data appeared at and It's thanks to Basil (I only know his tag) that I managed to figure it out. I used the PAST programme to do so.

What does it show? Time is on the Horizontal axis and intensity on the vertical one. Well the ice age looks good.... Nice and blue. (between 240 and 600?) Compare it to The Dalton minimum which is clearly visible on the top graph.


Interesting ideas here

Interesting thought of the Jovian influence on the Sun. So I went to see how far away Jupiter is from the Sun. The earth is 93 million miles or 150 million km from Sun, and the Sun’s actifity can be seen (aurora, etc). Jupiter is 483 million miles or 779 million km from Sun. How exactly does Jupiter influence the sun way back there? With a very big stick? I think not. Jupiter doesn’t influence the Earth in any way I know of (perhaps I’m wrong, and if so, I stand corrected) so how can it influence the Sun. Saturn is 886 million miles or 1428 million km from Sun and Uranus 1782 million miles or 2974 million km from Sun and neptune 2794 Million miles or 4506 million km from Sun. I think the arguments about gas giants are perhaps weak. By my math If you could travel at I mile per second, you could travel 3153600 miles per year and you’d take a long time to reach those gas giants. Even Voyager 1, travelling at 520 million kilometers per year took a long time.



On the sunspot front, remember “one swallow doeth not a summer make”

Lanscheit's ideas (

This planetry influence Idea ...

I stand corrected, just read this. “While the work of Mausumi Dikpati suggests that meridional flows in the sun’s convective layer may allow us to forecast sunspot activity , other forces may also be at work. In particular, the giant planets in the solar system may play a role through the gravitational pull they exert on the massive amount of fluid flowing in the outer layer of the sun.
Curiously, this gravitational force can be expressed as a Fourier series whose most important terms have interesting periodicities: one of these coincides with the 11-year cycle of the sunspots. What we may be seeing, therefore, is the direct influence of planetary tidal forces and their effects on the stability of the magnetic loops created in the meridional flows in the sun’s convective layer. These forces could be a major factor in the cycle of magnetic loops believed to create the sunspots.
Jupiter is the largest contributor to the solar plasma tides. It may eventually transpire that its influence contributes to our climate
from Sun.  Is it gravity, or magneetic forces that operate on these distances?

For those of you interested in whether a problem with “edge distortion” seriously detracts from the original image, I’ve done a “quick and dirty” analysis as suggested by Damek. In the following image, we have the original wavelet, through the most recent month of 2008, at the bottom. Above it, in the middle, is the wavelet cut off at 2000. And at top, is the wavelet cut off at 1980.

Here’s the link:

There are two things to observe here, I think. For evidence of “edge distortion” look at what happens in the top two images where the edge splits an 11 year cycle, revealing only the first part of it. What you see of it is more elongated than in the bottom image. But something else is happening too. The pattern of lower frequency signals is being altered. This isn’t “distortion.” It is the result of the pattern “weak” signals being altered simply because we’ve altered the length of data period used to divine them. For instance, when I do a periodogram on the entire period of data, there is a peak at ~104 years. When I cut off the data at 1980, that peak shifts to 92 years. Now given that we’ve only got a little over 250 years of data, it is not surprising that these low frequency spectra are going to be very sensitive to changes like this. And so we try not to read too much into the lower frequency results.

But personally  I don’t think that means that we don’t look at them at all, or ignore them completely. Obviously, the 11 year pattern is itself uncontroversial. I think Leif has conceded the existence of ~100 year cycles in solar activity, but would be quick to add that the exact duration of them is highly uncertain, and that would be right. In between, I think, that the wavelet analysis, wherever you end it (and arbitrarily ending it before the most recent available data strikes me as a kind of “cherry picking”) shows some heightened activity on a Hale cycle frequency. And it — the 22 year cycle — is there in the sprectrum/periodogram data as well. It is certainly not as strong as the 11 year cycle, but it is there.The colors represent the amplitude of the signal. And of course, the amplitude of the 11 year solar cycle does die and come to life every 11 years or so. It is pretty dead right now, and we’re all curious about when it is going to show signs of life. That’s what this discussion is really all about.

Some more links

This seems to show the sun 'flatlining',%20SW,%20and%20Solar%20Data.pdf

and more here

The award winning blog, 'watts up with that' features more on this.


The more I read, the more convinced I become that a serious solar minimum is likely and that the economic effects will be felt, especially if volcanic activity increases, which it seems to do as solar activity diminishes.

The influence of changes in the terrestrial climate (both global and regional) on almost all the aspects of social and economic activity of mankind is tremendous and doubtless. For example, the well-known problem of global warming has already transferred from the field of pure science into a global political sphere. Is the global warming a result only of the greenhouse effect or gives variations in solar activity also some contribution to this process? If solar contribution really exists, what is its extent? Can some other natural climatic phenomena lead to increase of the global temperature? The answer to these questions will provide us with information about the behavior of climate in the future and, hence, is of a great importance for the humanity. But it is evident that a precise and reliable forecast needs detailed information about the variability of climatic in the past and its causes. The knowledge in this domain is, However, still quite poor and has substantial gaps. Direct temperature records usually cover no more than the last 100-150 years. Series of measurements of different parameters of solar activity – the important source of climatic changes –are also short. The longest of them – the record of Wolf numbers – started around A.D. 1700. Other direct data concerning activity of the Sun and terrestrial and interplanetary phenomena are even shorter. Despite that the presence of a link between Sun’s activity and Earth’s climate has been claimed in many works, are the conclusions often based on relatively short time scales while the question about long term (centennial and multicentennial) solar modulation of climate is much less investigated.

Methods of dendrochronology, give us an opportunity to fill one of these gaps. The temperature reconstructions, based on ring width, obtained recently provide information about past climate up to 1000 years ago and more. Annual reconstruction of northern Fennoscandian July temperature, obtained at the University of Helsinki, is today one of the longest known series and covers the time interval since A.D. 50 (about 2000 years).

Stable isotope 13C concentration in tree-rings is another climate proxy. It reflects summer temperature, environmental conditions and precipitation regime. The concentration of 13C in trees from northern Finland is measured in the Dating laboratory at the University of Helsinki.

Information about the solar activity in the past can be obtained by two ways. First of them are data on concentration of cosmogenic isotopes (14C, 10Be) and nitrates (NO3- ions) in terrestrial archives. Cosmogenic isotopes are generated in stratosphere and troposphere due to galactic cosmic rays (GCR), which are strongly modulated by Sun’s activity, included in a number of geophysical and geochemical processes and finally fixed in tree-rings (14C) and polar ices (10Be).

Nitrates are formed at high altitudes in the atmosphere, precipitate and are finally captured in polar ice. Because a large part of nitrate is generated due to energetic solar protons, the nitrate record reflects the flare activity of the Sun. Available cosmogenic isotope and nitrate records, usually cover the last few centuries but the longest of them – the decadal radiocarbon series obtained at University of Washington –starts from 12 620 B.P.

Historic data are another source of knowledge about the Sun’s activity in the past. The most complete catalogue of the ancient oriental sunspot observations made by naked eye, (B.C. 165 – A.D. 1684) is the longest historic proxy of solar activity. Works made in the Central Astronomical Observatory (Pulkovo) proved that the catalogue contains quite reliable and valuable information. The performed researches have shown, that new original statistical approaches makes it possible to extract from descriptive historical data such information as frequency and amplitude components of the long-term solar variability, period of solar rotation and probably north-southern asymmetry of activity over a two-millennial time scale. It should be noted that not only Sun but also a variety of terrestrial and extraterrestrial phenomena (volcanic activity, influence of Moon and large planets, biospheric changes, human activity) could affect climatic changes at different time scales. To separate the possible solar contribution from that of other factors is another problem that needs complex statistical (spectral, correlation, cluster) analyses of all the direct and indirect indicators of climate and all phenomena, which may cause its changes.

First results of statistical analysis, made for some of the data mentioned above, has given us evidence that the century-type time variation, present in many climatic series during 1-2 millennia, very likely was caused by acting of centennial cycle of solar activity (Gleissberg cycle). The analyses show that this solar-climate link was more evident in northern Fennoscandia. It allows us to hope that the next annual northern Fennoscandian temperature reconstruction, which is under preparation at the University of Helsinki and which will cover the last 7000 years, can provide valuable information not only about regional climatic variability in common but also about the history of the connection between Sun’s activity and the terrestrial climate during seven millennia.

Despite the fact that some progress already has been made, is the main work still to be executed. A lot of data obtained recently (temperature dendro-reconstructions, data on cosmogenic isotopes, volcanic activity and other phenomena carrying valuable information from the point of view of this project) still need thorough statistical analysis. Comparison of tree-ring temperature proxies with other climatic indicators is desirable for a more reliable reconstruction of climatic variability in the past. The series of measurement of 13C in tree-rings from northern Finland, which have been started in the Dating laboratory of the University of Helsinki and which will cover the last centuries, should help us to realize this purpose. Including 13C measurements of Baltic tree samples should help us to trace regional temperature differences and, therefore, to analyze the strength of local climatic effects over multicentennial time scale. A serious problem is connected with the fact that all data sets involved into analyses are very non-stationary and many of them contain a strong noise component. Moreover, noises, contained in climatic signals, often are “colored” and non-additive. Hence, the analysis of time structure of the available datasets and revealing possible interrelation between them is difficult. It should also be noted that many historical and paleo-data have irregularly distributed gaps, which complicates substantially the analysis. A solution of these difficulties demands considerable improvement of modern statistical methods (including wavelet analyses, chaotic dynamics and fractal geometry) and, probably, elaboration of new methods. Our knowledge about the solar activity in the past, especially about long-term changes of solar irradiance – likely an important factor affecting terrestrial climate - also should be enhanced. Analysis of ancient aurora borealis catalogues is anticipated to supply us with more detailed information about solar activity than decadal radiocarbon series and ancient naked eye observations. The measurements of the cosmogenic isotope 14C in tree-rings from northern Finland and Baltic will help us to restore the intensity of GCR during the last few centuries and to clear up a question about possible regional variability of concentration of radiocarbon in the atmosphere. Reliable reconstruction of solar irradiance needs further progress both in our knowledge about long-term changes of solar magnetic dynamo and about time evolution of the helio-latitudinal structure of solar activity. Investigation of the mechanisms of solar influence upon Earth’s weather and climate, which still is unknown, demands also progress in our knowledge about solar modulation of interplanetary magnetic field and galactic cosmic rays intensity at the Earth’s orbit, and about influence of solar and galactic cosmic rays on the upper atmosphere.

Obviously the solution of these problems can be attained only by combined efforts of specialists, working in dendroclimatology, paleoastrophysics, mathematical statistics, geophysics, magnetohydrodynamics, solar physics and cosmic plasma physics.

In spite of a lot of difficulties, the studies of the mechanisms and effects of solar activity on terrestrial climate, and their evolution during the last few millennia, are very important and valuable. The answers to these questions allow us to increase reliability and correctness of global and regional climatic prognosis for future centuries that is of tremendous importance for all the humanity.


What do I think then, for the future? Its very strange, given the harsh temperatures in the southern hemisphere and the wild bush fires in Australia. Is the sun really in a magnetic problem? Human activity (arson) rather thatn hot temperatures seem to have caused these problems. It's difficult to predict the end of this period, and given that hatjhaway et al get it wrong, perhaps I'm mistaken to take a stab. But here goes

In my opinion

Solar cycle 24 won't start to increase until over 1000 spotless days (counting from the end of c 23).(At the moment its 500 plus).Looking at this  updated page here

It seems things are pretty grim.So 2011 would be a good time to think about a reasonable summer in Northern hemisphere. But don't forget