What modulates our Sun? The majority of science work on the principle that the Sun is self modulating and each solar cycle is a product of a random number generator. There are others that suspect the Sun is modulated by the planets with a special emphasis on Uranus & Neptune. Thanks to Carl Smith who has recently left us we have new knowledge that significantly adds to Jose, Landscheidt & Charvàtovà's work.

Geoff Sharp

Earth's Future Climate.


Click on pic for larger view

Reader Ron De Haan suggested a graph showing future Angular Momentum Disturbance Strength might be of interest. We only have JPL data out to 3000AD so this is the current limit, but the outcome is indeed very interesting. If the Solar activity follows the Angular Momentum trend we are headed for another Medieval Warming Period type era on even a grander scale.

After the Landscheidt Minimum which will be short and sweet, there looks to be another Dalton type event which is not considered all that strong. After that the planet will stay on a warm plateau for hundreds of years, lets hope we have learned by then that the warming we will enjoy is a natural state. The graph shows us how unusual the preceding strong Grand Minima are in our history, which was ruled by strong Type "A" disturbances or as Gerry calls them "Retrograde Bumps". From here on the AM strength is moving to weak and gradually the disturbances are moving back to Type "B" which are known for periods of reasonable solar stability. So there is no need for pessimism, our children will have it good.

The JPL data used to create the AM graphs as per Carl's Graph has a range from -3000 to 3000, but I am working on another quantifying method using purely the Jovian planet angles which should allow us to check against the complete Holocene record as well as looking out as far as necessary. Thanks to Tayla Sharp for helping with the graph.




Strike 1,2,3

Hi Gerry,

I am glad you asked, I think you are missing the retrograde bump before 1650 that occurred at 1610, its not a lot different to the shape that started the Dalton at 1790. Also there is a 3rd strong Type A that follows up at 1690 which gives the Maunder 3 good hits which keeps the Sun inactive for 90 years, this is rare. The AM strength started to weaken after that as can be seen by the Dalton patterns which transpired into reality. This time around the first hit is quite weak (SC20) but still manages to have its affect on one cycle, like you point out the current disturbance is just like the middle phase of the Maunder but that is all we will get, there does not look to be much happening on the 3rd phase. So without the beginning and also the follow up I think we are in for a short sharp decline that will recover after 2 solar cycles. My quantification at each GM centre is a combination of all 3 hits that come with the centre, that is the important distinction, one hit is not enough.



Thanks Gerry, there are still many unknowns in this area, so if I am right there will be an element of luck involved (assuming my logic is correct) There is still no explanation why 1 retrograde bump causes 2 cycles to be flat and other instances like 1830 that only caused 1 cycle of low activity even tho the disturbance was strong (Ian Wilson has a theory that is being tested again right now).

Theodor didn't expand the data like Carl did, so was unable to see the individual disturbances, but did notice the low points caused by S/N/U conjunctions with J opposite that occur each side of the disturbances. That's why he incorrectly predicted a downturn in 1990 and then moved on to 2030, not realizing the disturbance what creates grand minima was actually in between. But he was very close and certainly on the right track, without his pioneering work we might still be in the dark today.

UPDATE: Here is the original graph that Landscheidt used in his predicted 1990 and 2030 grand minimum. The red dots highlighting those years. Also included is his original text showing his reasoning. The level of detail between his data and Carl's is many orders different, but you can see the general trend in the past followed roughly by grand minima. When the AM or torque dips below the dotted line there is a solar slowdown, but he is just picking up markers that occur around the same time and not seeing the actual driver. Note that Landscheidt predicts this grand minimum to be of a similar strength and timing as the Maunder....I wonder what he would think now, if he were still with us today?

Fig. 11:Time series of the unsmoothed extrema in the change of the sun's orbital rotary force dt for the years 1000 – 2250. Each time when the amplitude of a negative extremum goes below a low threshold, indicated by a dashed horizontal line, a period of exceptionally weak solar activity is observed. Two consecutive negative extrema transgressing the threshold indicate grand minima like the Maunder minimum (around 1670), the Spoerer  minimum (around 1490), the Wolf minimum (around 1320), and the Norman minimum (around 1010), whereas a single extremum below the threshold goes along with events of the Dalton minimum type (around 1810 and 1170) not as severe as grand minima. So the Gleissberg minima around 2030 and 2200 should be of the Maunder minimum type. As climate is closely linked to the sun's activity, conditions around 2030 and 2200 should approach those of the nadir of the Little Ice Age around 1670. As explained in the text, the IPCC's hypothesis of man-made global warming is not in the way of this forecast exclusively based on the sun's eruptional activity. Outstanding positive extrema have a similar function as to exceptionally warm periods like the Medieval Optimum and the modern warm period

UPDATE 2: I found another graph that Landscheidt uses in "Solar Eruptions Linked to North Atlantic Oscillations" that shows that he DID have access to information at a more precise level. Here he shows the "camel humps" like we see in Carl's AM graph but this graph is based on torque measurements (which are similar to AM). Landscheidt calls these perturbations PTC (perturbed torque curve) and he states that they occur every 35.8 years, and are responsible for "phase reversals". My research and Carl's suggest the PTC type disturbance does not occur on a repeating pattern, but only when Neptune & Uranus are in or near conjunction. This I think is further evidence that Landschiedt perhaps missed this vital peice of the puzzle????


Future climate

I'm sorry, I don't understand what the grapoh is trying to tell me. Why is the current and Dalton minium at so much a higher level than the Mrauder minium. Why are some of the points which are supposed to be warm weather in the future lower than the current minium.

Grand Minimum Strength

The Maunder Minimum is a very strong disruption over a prolonged time period, the Dalton was only a shadow. The difference being the strength on the Angular Momentum Disturbance. This disturbance strength varies each 172 years and is a product of the positions of the big 4 each time. The Maunder had at least 2 strong hits with another smaller hit around 1610 (the records are weak around then), while the Dalton only really had 1 major hit. During the past 400 years we have had the possibility of 3 hits per 172 year cycle. The future Angular Momentum Disturbance Strength tells us there are no big grand minima likely, this means the Sun does not have to drag itself out of deep grand minimum effectively allowing its inertia to continue at reasonably high levels.

Impending Ice Age?

Hi, this website looks fantastic and I was reading these predictions for the future of the Earth's climate and was wondering whether it takes into account the coming of the next ice age? From the Angular Momentum predictions, it certainly looks as if we will enjoy a relatively balmy climate for a while to come, but I am slightly unsure whether an ice age will occur relatively soon? There are theories which suggest it could occur this century, and some research using Antarctic ice cores going back 740,000 years which suggests it is another 15,000 years off. I wonder what you think on these suggestions? I would also like to bring up the work of Ferenc Miskolczi who has produced a theory which refutes anthropogenic global warming, which has been carefully ignored and hasn't been disproven. I wonder if you've heard of his work, since it really could be a Rosetta Stone of climate science? After doing lots of reading into the subject of climate change, I am inclined to agree that it is a natural, cyclical process, driven primarily by the sun. But please could you address the questions above, and in a relatively simple way, so I can understand it. Thank you. Smile

The slide is coming...

Hi, thanks for the compliment. You are correct with your ice age comments which could happen at any time. There are 2 forces in play that are both governed by the outer 4, one is the solar output versus the changing orbit pattern of Earth. I am surprised there is little research into the Milankovitch cycles in regard to orbit shapes and when we should expect an ice age type cooling. But my predictions are assuming this impending doom is some way off, which I do mention in my just published paper.

I have not seen any work by you have a link?



He has produced a theory called "Saturated Greenhouse Effect" in a Quarterly Hungarian Meteorological journal. Here is a link to the theory:

and here is a link containing a letter from Miklos Zagoni, who after studying Miskolczi's work, reversed his views on global warming/climate change. This letter is very interesting in that it shows scientific suppression and the political element to the whole debate:

Just to clarify, the oncoming Landscheidt minimum is expected to be a mini version of the Maunder Minimum in duration, but is likely to be as intense, and sometime after that there will be a Dalton Minimum which won't be as intense? So we'll experience a "Mini" Little Ice Age towards the middle of this century?

Another exciting piece of potential evidence as to solar-terrestrial relations is in this website which shows a possible link between solar activity and seismic and volcanic activity?!

Finally, in terms of planets affecting the Sun, it seems to me to be similar to the Moon having tidal effects on the Earth? Perhaps that could be an analogy?

Thank you. Smile




Thanks for the links..I will review and come back.

In regard to the Landscheidt minimum the outlook is for a Dalton like performance, although it might be deeper than the Dalton it may only cover 2 cycles. This is way different to the Maunder which lasted much longer and deeper, the next downturn after the Landscheidt might be slightly stronger again but these predicted downturns do not compare with Maunder/Sporer type events. The LIA was a true golden period that does not come along often.

Tides and angular momentum are both children of gravity, personally I think tides are of lesser importance but may have some involvement with the 11 year solar cycle.


Sorry, I didn't mean that the tides are involved in the solar cycle, I just meant that as the Moon can affect a body such as Earth, which is much larger than it, so profoundly (tides), then the planets being much smaller than the Sun could also have profound effects on the Sun. Just a comparison/analogy for non-scientists like me in order to understand such processes!

Small player

Tides have potential, but personally I think they are over rated. The bigger gravity effect is the planets control of the Suns path around the SSB.

Ice Age and Landscheidt

Here is an interesting piece of evidence which suggests we are half-way through the current interglacial, using an interglacial which occured 420,000 years ago known as Termination V. This interglacial had very similar Milankovitch cycle conditions to the Holocene and lasted roughly 25,000 years. See pages 150-152 of following:

Therefore, we probably needn't worry about an impending ice age.

And lets hope that the oncoming solar Grand Minima are no worse than the Dalton, as a Maunder-type event would prove disastrous for the world and particularly agriculture. Perhaps Landscheidt's prediction of an oncoming Maunder Minimum and LIA-type event was also influenced by the fact that he wanted everyone to see how important the sun is to climate and how grossly exaggerated AGW is? Perhaps it was (along with the fact that from his evidence he believed a new Maunder Minimum would come) a display of disapproval towards current climate science, and was thus hoping that such an event would bring global temperatures right down, thus showing the sun's importance, a subsequent change in scientists' and the people's views on climate change and shutting alarmists and governments up?

I do NOT mean to discredit Landscheidt and his work, after all, it certainly is a giant leap forward for solar/climate science, but I just want to suggest some potential factors influencing his (hopefully false) prediction. The only reason why I am not ready to completely dismiss the idea of a new Maunder Minimum/LIA is that Landscheidt had such good high hit rates with his predictions and was able to predict the end of events such as the Sahelian Drought in advance, all due to solar activity. But as you say, he obviously predicted a Grand Minimum wrongly for 1990 and perhaps he didn't expand the data as much as Carl did, and also, no-one is perfect, and no-one gets everything right all the time. And as you say, yours and Carl's work is a great addition, development and improvement on Jose's and Landscheidt's work. So lets hope that the sun gradually becomes more stable over the next few centuries, and hopefully when the next bout of deep Grand Minima occur, we'll be better prepared!


Thanks for your insightful comments. Landscheidt was the pioneer, and now we have a lot more data that suggests the Sun will not enter a 100 year grand minimum as some recent papers suggest. The next 20 years might be cooler but the overall trend is toward a warming plateau.

But ice ages are completely different, two different streams of influence. One is a varying solar output, the other more related to the distance from that output.

1,500 climate year cycle

There is an interesting paper here:

which suggests a cycle of 1,500 years +/- 500 years of warming periods during the Holocene, namely the Minoan, Roman, Medieval and Modern Warming Periods being this cycle. In terms of mechanism it seems to me that it occurs when the sun is relatively stable, when the 172 yr downturns are fairly weak. So it seems that the orbit patterns and angles of the outer planets varies on this 1,500 year cycle? The paper also says that this warm period could last for  "centuries longer", which seems to go along with your Angular Momentum and solar activity predictions. We are 150 years into this warming period and the Medieval Warm Period lasted for 400 years or so, and I have read somewhere that the warming at the beginning of the Medieval was more pronounced/steep than that of our present one. The Romans reported warming between 200 BC to 400 AD. Of course this Grand Minimum will create a short downward spike in the global temperatures.

I liked your paper by the way (not being sycophantic) and I have printed a copy out for myself. I also like the winter prediction, and hope for a nice, cold winter! I also see that the temperature drop of recent months in the Pacific Ocean has been one of the most pronounced since records began. A strong La Nina perhaps?


Type B AMP event

Thanks for the link, an interesting read, no graphs or data but if they have studied that amount of data over the time periods stated there could be something in it. The weak downturns are when the Type A AMP events cant form and are replaced by Type B events which also vary in intensity but over a smaller range. Perhaps there is a cycle of weaker Type B events on a rough scale of every 1500 years, the recent warming periods you mention do align with periods of weaker Type B dominance which provides further backup to the theory. This is another nail in the coffin for those who follow the Babcock/Leighton theory that states the Sun does not follow a pattern and is a product of a random number generator. Usoskin had to re invent what constitutes a grand minimum so that the solar regular pattern of downturns would be hidden.

The NH winter is very interesting to watch, I am waiting patiently for the July PDO value.


GM Centres

Hi Geoff,

Could you please explain to me what the GM centres on the graph are and what they mean? From what I make out, the Grand Minimum after the Landscheidt (~2200) looks to be more severe, is that so?

Re: GM Centres

Hi, the GM is simply grand minima. Each 172 year avg return of grand minima come is different strengths and the amount of hits can also vary. The hits being the individual AMP events that occur on each wave. We are only really going to get one hit this time but the next wave will be slightly stronger. The GM centre is the centre point or middle AMP event which is usually when Uranus and Neptune are close. I simply total the AMP strength per wave and position it near the centre of that wave. So far it follows the isotope records quite nicely, given more time I will extend it back further.

Thanks, it does seem

Thanks, it does seem blindingly obvious now that you have explained it! Do you have a link to a graph which compares the various "hits" of the current GM and the one at ~2200?

ssb graph 2000-2500

Click for a larger view.

As you can see we are heading into a phase change where the type B AMP events will start to rule. The beginning of this is 2110 and the reason for the slight upgrade on the current grand minimum. But not much in it.

There is a paper here which

There is a paper here which says that lunar motion and consequent tidal perturbations affect the oceans in a cycle of 1,800 years. It says that stronger tidal forcing from the moon "mixes" the oceans and allows cold water to surface, but when it is low, there is less mixing, and the surface stays warmer. This would have an effect on air and land temperatures because the oceans are so important to climate. However the paper is dismissive of the Sun affecting the climate on similar time scales. I think it could be a combination of both (with many other factors also to consider), but it is far from proven. According to the paper, the low tidal forcing from the moon which started 100 years ago could last for another five centuries, and therefore we will experience general warming in this time. Here is a link if you want to have a look:

Many thanks go to Carl's brother Dave for providing the Domain, Server and Software.