A new paper published by the Astronomical Society of Australia titled:
Does a Spin–Orbit Coupling Between the Sun and the Jovian Planets Govern the Solar Cycle?
contains a warning about earthly climate change not immediately obvious from the abstract:
Based on our claim that changes in the Sun’s equatorial rotation rate are synchronized with changes in the Sun’s orbital motion about the barycentre, we propose that the mean period for the Sun’s meridional flow is set by a Synodic resonance between the flow period (~22.3 yr), the overall 178.7-yr repetition period for the solar orbital motion, and the 19.86-yr synodic period of Jupiter and Saturn.
According to an interview with Andrew Bolt, of the Australian Newspaper, Herald Sun, Ian Wilson, one of the authors explained:
It supports the contention that the level of activity on the Sun will significantly diminish sometime in the next decade and remain low for about 20 – 30 years. On each occasion that the Sun has done this in the past the World’s mean temperature has dropped by ~ 1 – 2 C.
###
Hmmm, I’m not sold on this idea. This is a lot like what Dr. Theodor Landscheidt proposes. I have a little bit of trouble understanding how the “mass at a distance” gravitational effects of Jupiter and Saturn could have much effect on the solar dynamo.
I’m sure both my readers, and Dr. Leif Svalgaard, who regularly monitors this blog, will have something to add to provide additional insight. – Anthony
Discover more from Watts Up With That?
Subscribe to get the latest posts sent to your email.
Leif Svalgaard (14:21:40) :
Here is a thought experiment: Add a pea to the solar system…”
What good is an orbital mechanics thought experiment without numbers? (Don’t answer that.) Let’s assume a pea is 2 grams. I think it’s less, but 2 works is nice because the mass of the Sun is 2×10^33 g. To place the barycenter of the Sun-pea system on the Sun’s surface, the pea will need to be 10^33 solar radii away. The solar radius is 7×10^8 m, so the distance is 1.4 x 10^42 m. Astronomical Units (the distance from Sun to Earth) are easier to work with, 1 AU is 1.5×10^11 m, so the pea is about 10^31 AU away. The orbital period will be 10^62 years, just long enough for the 2 gram mass of the pea to pull on the sun with a force equivalent to a 1/2 x 10^62 grams in Earth orbit. Wow – that’s a lot less than the mass of a pea molecule! Or proton or electron.
I’m a lot less impressed with barycenter arguments now. And a lot more impressed with the power of peas. Go in pease. Peace be with you.
As I understand it the hypotheis of the Danish National Space Center goes as folows:
‘Active’ sun → enhanced magnetic and thermal flux = solar wind → geomagnetic shield response → less low-level clouds → less albedo (less heat reflected) → warmer climate
Less active sun → reduced magnetic and thermal flux = reduced solar wind → geomagnetic shield drops → galactic cosmic ray flux → more low-level clouds and more snow → more albedo effect (more heat reflected) → colder climate
That’s how the bulk of climate change might work, coupled with (modulated by) sunspot peak frequency there are cycles of global warming and cooling like waves in the ocean. When the waves are closely spaced, the planets warm; when the waves are spaced farther apart, the planets cool
” Robert Wood (16:16:46) :
Anna V @21:33 Imagine the baricentre being a great christmass pudding stirring paddle, mixing up the convection cells and deep internal currents that produce the solar magnetic field. ”
Not really. I am with Leif in this. The barycenter is a virtual spot that “corrects” for all the wobbles in motion of a many body gravitational system. Everything revolves around the barycenter and makes visualizations simpler, that is all.
Its ( barycenter’s) motion though is interesting as a “clock”, a “location indicator” of how the tides, small as they may be, change on the fluid mass that is the sun, and there seem to be changes that can make up beats.
I do not know if they do, I do not know if (as if with the CO2 greenhouse effect hypothesis 😉 ) there is a huge positive feedback that can kick changes in the plasma and the way the magnetic field is generated in the sun. From the little I have read there are exponential feedbacks needed to describe the sun’s magnetic field anyway, so maybe regular even if tiny beats in specific directions can trigger huge effects. May be.
It is evident that a sun model has to be proposed for this hypothesis to have any real value and testable outputs.
I am an interested observer on this one.
anna and others: Just as we can do for the Earth, it is now possible to probe the interior of the Sun using helioseismology and neutrino detectors. These new tools have confirmed that our theories about the interior were correct to high precision. We can even measure the interior flows and rotation. The only real surprise is the discovery that the interior of the Sun [the inner two-thirds radius] rotates with nearly constant speed contrary to our expectations [of constant speed on cylinders]. Other than that, the sun is just as we thought it should be, even to the point that the unexpected low neutrino flux turned out not to be due to errors in our knowledge of the energy production or structure of the sun, but to the neutrinos having mass [albeit tiny] so that they can change ‘flavors’. There are no huge ‘sloshes’ of great masses inside the Sun. The core of the Sun is a quiet and stratified place, not even having any convective movements. Nothing at all that seems to respond to any outside influences.
“Leif Svalgaard (16:45:56) :
“Carsten and others: I do not have to follow the laws of physics. I can put the pea where I want when I want. What I tried to show was the absurdity of the barycenter theory of sunspots. I realise that I have failed, as so often before, as I have already remarked. The predicable next step is accusations of ulterior motives, hidden agendas, holocaust denials, AGW, Al Gore church fellowships, unsavory oil industry money, etc, etc. We don’t need any more of that, so, maybe, this is enough for now.”
Leif: I was really trying to participate in a scientific debate, but when the argument is that the laws of physics do not apply, it gets complicated. I cannot see a valid reason why the laws of physics should not apply, it gets absurd. I could for example say that your formula for center of mass does not apply (I am not saying that).
The question of motives, accusations etc. has no place in my opinion. I have no such views regarding your position. All I am interested in is discussing the science.
It appears that your argument for rejecting solar inertial motion around the barycenter as a possible cause for modulating solar activity is that the sun is in “free fall”. It is in free fall, but I think we have to take into consideration the fact that the sun may not be 100% homogenious. I read somewhere that sunspots are areas of higher buoyancy (i.e. lesser density) for example, ther might be other effects too. It does not seems entirely incredible to me that if you take a quasi-spherical non-homogenious body like the sun and let it move along a variable radius orbit (where the radius keeps changing) that internal inertial forces may cause some stir-ups.
Regarding tidal effects I think that is probably a non-issue. The tides caused by the planets on the Sun are extremely small (<1mm) and most likely neglible.
Here is a simpler barycenter:
“Where is the barycenter of the Earth-Moon system located?
The center of mass of the Earth-Moon system, is a point in space about which the Earth and Moon appear to orbit as they travel around the Sun. It is located exactly along the line that connects the center of the Earth with the center of the Moon. The average distance between the centers is 384,405 kilometers. The distance from the Earth’s center to the barycenter is
D = M(moon)d(moon)/(M(earth) +M(moon)
0.012 x 384405/(1.00 + 0.012
4641 kilometers
where the mass of the Earth is 1.0 and the mass of the Moon relative to the earth is 0.012. Now, the radius of the Earth is 6,378 kilometers, so that means that the barycenter is located INSIDE the Earth about 1707 kilometers below its surface. Does anything weird happen there? Not that anyone can tell. “http://www.astronomycafe.net/qadir/q665.html
A barycenter is a mathematical point, in this case of the earth and moon system.
The only connection between earth and moon is with gravity, and that is tides. The barycenter will move synchronously with the tides since the latter are a result of the rotating moon and gravity pull. It does not cause the tides, it is just mathematically correlated.
A stars wobble, is it’s movement observed from an outside reference, around the common barycenter of that star’s solar system. …. yar? …. Not the Planet’s gravitational “pull” on the star…. Where that misconception arises is when a planet is close and massive so that the wobble is fast and easily observed?
Have I got that correct Lief Svalgaard?
Carsten,
“It does not seems entirely incredible to me that if you take a quasi-spherical non-homogenious body like the sun and let it move along a variable radius orbit (where the radius keeps changing) that internal inertial forces may cause some stir-ups.”
Shape or consistency don’t make any difference. All masses react the same way to both gravity and inertial forces. And in this case, the two cancel almost exactly – the difference between them being the tides.
Unlike Leif, I don’t necessarily think this makes an influence impossible. A force able to lift matter a fraction of a millimetre against the sun’s surface gravity, when sustained in roughly the same direction for 6-9 days (the period between high and low tide on the sun) could mount up to a noticeable velocity change. If then magnified by being forced through channels (along magnetic flux tubes, for example) it could get even faster. That’s why tides on Earth are more significant than their theoretical 36 cm height would suggest, and how tiny Coriolis forces can spin hurricanes, so I don’t see it as necessarily impossible there could be a tidal effect on the sun.
Or there may be other mechanisms. The tides may have more of an effect on the corona – the magnetically energised atmosphere outside the sun. Or maybe the sun can detect its own motions through the kinks it puts in the magnetic field in the outer solar system, far beyond Jupiter’s gravitational influence. Jupiter has a significant radio presence, and I gather that the other planets with magnetic fields are connected by flux tubes to the sun. So suppose you get flares occurring preferentially in their direction, like lightning rods, and suppose flares are important for the mechanism of the sun’s magnetic dynamo. (The document I linked above mentioned a speculation that flares allowed the sun to dump a plasma flow property called helicity, which has a disproportionate effect on the dynamo because it is partially conserved.) This could then lead to systematic changes in the external field, which affects the internal field, which affects the energy transfer between convective kinetic energy and magnetic energy, which affects the large scale motion.
All of the above is ill-informed guesswork, though. The situation is that the initial hypothesised mechanism of the barycentre-relative motions shaking the sun around has been falsified, and the next most obvious/plausible tidal influence shown to be smaller than expected. We have to see things clearly as they are, and pause to think again. But it is a classic ‘argument from ignorance’ fallacy to suppose that because one can’t think of another mechanism (or any mechanism), that therefore there isn’t one. That’s exactly what the AGWers did with CO2.
The possibility has to be seriously entertained that the correlations seen are mere numerology, and there is no connection. Until someone can come up with a plausible, testable mechanism, that is still the most likely option. But that doesn’t mean the science is settled and the debate over, and it doesn’t mean we shouldn’t allow such ideas to be published, or to be heard and discussed, or for people to try to follow them up. It certainly doesn’t affect any of the reasons to be sceptical of the AGW hypothesis.
We Sceptics have to have higher standards than the AGW faithful, and not simply jump on every bandwagon that looks like it might be going in our direction. The point of being a Sceptic is to be sceptical of all arguments (whether published in peer-reviewed journals or not, in our favour or not), so we don’t wind up fooling ourselves like the AGWers have.
Leif,
“These new tools have confirmed that our theories about the interior were correct to high precision.”
See the document I linked to above for some of the aspects of the solar dynamo that don’t in fact fit theory, and aren’t understood. There’s a section towards the end that goes through them.
http://arxiv.org/PS_cache/astro-ph/pdf/0405/0405052v2.pdf
Mr Svalgaard,
My, with all the questions put to you, you’d think this was your blog. I must thank you for your tireless answers despite the frequent “trolling” you get in return.
Anyway, you’ve explained at least to me that this effect of the planets on the sun is only ~1mm or so. You’ve even linked me to the page that explains why the Sun, despite having 100 times the gravitational influence over us compared to the moon, has a smaller associated tide. That one got me for a bit. So, while the barycentre calculations may correctly identify an angle of action, the force of the vector is minimal. Ok.
You also state that “the core of the Sun is a quiet and stratified place, not even having any convective movements.”
Anyway, my question relates somewhat to the “100,000,000 cycles” effect – with such a quiet internal core, if something was to be perturbing it by only a millimetre – would the “bathtub start sloshing”? Such a quiet, calm interior seems to be what that hypothesis calls for – a serene body that has little else to perturb it. While the tides as we imagine them would be “lost in the noise” in the noisy outer parts of the sun, the quiet centre would still be being moved (to presumably a proportionately smaller extent). While on its own, the movements may not be significant, the “ripples” as they are amplified by cycle-on-cycle additions, and their traversal through the various strata of the Sun, could resonate, if the energy/inertia has no-where else to go.
In that view, the observed quiet (presumably, with some margin of error sufficiently large so as to not be able to preclude this speculation) centre of the Sun would be like the open water, only moving by the half metre or so, whereas the outside of it would be like the coastal areas that see tides.
Again, thanks for your continued follow-ups!
There is a lot of discussion of how the models disprove this or that, but the ugly truth is that the Landscheidt’s Gleissberg minima and maxima quite closely match up to know climate events here on Earth (and presumable on Mars and Venus if we had the ability to peer down the halls of time on our sister planets).
Computing less that 1mm effect does not mean that was indeed the effect in reality when in fact, it may have been less or greater if observed. This is exactly the same problem faced by GCMs and their predictions of runaway global warming which flies in the face of many ugly ground truths.
Despite the assurances of Dr. Leif, I very much doubt we have the resolution to determine the effect of movement of the solar system barycenter on the substance of the sun. Do we choose to ignore the ground truth of the Gleissberg cycles and climate events because we don’t know how to model it?
To blindly rely on models is falling into the same trap as the Global Warmers.
Landscheidt managed to predict the ENSO phases using solar barycentric oscillations and had shown that these same oscillations correspond to the variable period of the Gleissberg cycle and finally that extremes of the angular momentum in the oscillations match historic climatic events.
You can see the correlation here: http://bourabai.narod.ru/landscheidt/new/Fig11L.jpg
It is always good to remember that a model does not represent reality and when confronted with a contradiction, check the your assumptions.
Now that I’ve had time to think about it, and crunch out a few back of the envelope calculations, I will agree that the angular momentum changes between the sun and the barycenter are made up for by angular momentum changes between the other planets and the barycenter. It’s another one of those situations where the equations balance out quite nicely.
So no, the sun does not need some massive angular momentum transfer between its internal and orbital momentums.
I’d look a lot less stupid if I’d done the math before my first post…
Carsten: Perhaps I didn’t express my self clearly enough regarding the laws of physics. I was referring to how I move the pea around. I can place the pea where I want and then place it elsewhere without worrying about how I get the pea from point A to point B as this is a thought experiment. That a real pea according to the laws of physics could not survive the accelerations associated with my moving it in my thoughts is what I’m allowed to disregard. A pea at a certain distance moves with a period given by Kepler’s third law, by I’m allowed to move it anywhere else as I please in my thoughts not bound to Kepler’s third law. It is like when Einstein once said that he got insight into the theory of relativity by asking what a light wave would look like if he could move along side it at the speed of light, regardless of the possibility of actually doing so.
That the Sun is not homogeneous does not matter. An Astronaut in free fall around the Earth is not homogeneous either [nor is the Earth], yet he fells no forces.
Now we have an interesting situation: We have two issues A and B. Several readers agree with me on issue A, but maybe not on B. Several readers agree with me on issue B, but maybe not on A. I suggest that I should not be the sole carrier of the burden of resolving the differences between these two groups.
Carsten Arnholm, Norway (00:24:45)
“Leif: I was really trying to participate in a scientific debate, but when the argument is that the laws of physics do not apply, it gets complicated.”
Leif was trying to simplify things. The only laws I noticed broken in his “Newtonian” universe were things like mass as a function of velocity (a pea weighs a pea no matter how fast), gravity not limited by the speed of light, the size of the universe, the age of the universe, and pretty much all the mass, energy, dark matter, and dark energy except the Sun and pea.
[The Sun] “It is in free fall” hey, you’re getting it! “It does not seems entirely incredible to me that if you take a quasi-spherical non-homogenious body like the sun and let it move along a variable radius orbit (where the radius keeps changing) that internal inertial forces may cause some stir-ups.” Well, not yet.
That the Sun is in orbit around some point in a Newtonian plane means that the Sun is being accelerated. So are astronauts in the ISS’s circular orbit, so would they if they were in an elliptical orbit. Without observation or some other connection with the outside world, neither astronaut nor Sun can detect the forces because they are both in free fall.
If there is some effect, it has some other sort of connection – tidal, magnetic, atmospheric (not in this solar system), or General Relativity (something no one has brought up yet).
It seems to me that once the laws of physics are violated in a thought experiment, then any conclusion drawn from that thought experiment are useless.
I remember a thought experiment whereby it could be proved that 1 equals 2. The trick was, half way through, there was a hidden divide by zero.
How to preserve the barycenter and angular momentum, if the mass of the system varies with time?
Lief:
I’ve been working a massive reconstruction of Jupiter’s atmosphere (a hobby) as I find the various meridional band depths quite illustrative.
So not knowing the science, but if I understand you, that without an equatorward conveyor then would it be that the sunspot fields aren’t getting – erm – “recycled” back to the equator.
Instead I might surmise the variable speed of the bands on the sun might go in and out of sync over time, yielding differential field elongation … some slower band periods less field stretching, other periods more, with respective sunspot levels. If I try to visualize what happens when the bands are furthest from unison, the more intense the stretching of the magnetic field might cause internal forces that increase the intensity of the system, and with that, observed magnetic strength.
Relative to the sun’s total output these are small variations that lead to changes in sunspot activity, solar wind, prominences and cosmic rays. As they are experienced on Earth by living creatures, it tends to matter.
If your reconstructed historical TSI values turn are higher I see a series of dilemmas: How the reconstruction impacts analysis of past temperatures, the temperature trend since the 1980’s particularly.
Speculating wildly here, but I also have to wonder if magnetic field flux might differentially warm the seas through metals in solution, akin to studies showing iron oxides helping align materials in solution rendering them more heat conductive. Or perhaps magnetized iron seeds algae with similar effects.
Granted the sun is in freefall and in its massiveness imparts its own intertial frame of reference, but then what imparts the sun’s wobble around the barycenter then? Or is it a perceived barycenter only from the POV from the planets?
Thanks for reading & sorry for the bad science. 😉
Steveo: you are conflating our knowledge about the conditions within the sun with our ideas about how the dynamo works. It is like this: we know a lot about the conditions of our atmosphere, we have thousands of stations, many satellites, observations galore, but we still can’t predict the weather or the climate with much accuracy.
MarkW: hasn’t grasped the idea.
Sam: Tidal effects depends on the distance between the center and the point where you measure the tides. As you approach the center of the Sun the tides get smaller and smaller to finally disappear at the center.
leebert: some of your questions may be answered here: http://www.leif.org/research/Percolation%20and%20the%20Solar%20Dynamo.pdf
Leif, if the gravitational pull from the other planet s is enough to pull the sun as far from the barycenter as they do, then they should be able to affect the solar cycle which is caused by a difference of spin rate between the center and surface of the sun. I’d be surprised that the gravitational effects on a dense core and plasma surface would be the same. We’re talking about cycles ranging from 11 to 100’s of years.
Lief,
Yer a scholar & a gentleman.
If I understand the gist of the paper, the percolation (superadiabatic) flow between the sunspots has opposite polarity, drawing the sunspots together, etc. Counterintuitive, but neat.
I’m still reading, but seems like all that’s required is simple local convection and equatorward belt convective magnetic recycling isn’t necessary.
MikeC: the gravitational effects on a pound of feathers is the same as on a pound of lead. And the planets are not pulling the Sun away from the barycenter. The barycenter [or center of mass] is a fictitious point calculated from masses and distances.
Leif,
Conflating? How so? One is a subset of the other. And I don’t get your comparison – I agree we don’t understand how the Earth’s atmosphere really works either, and not simply for lack of measurement resolution, but it’s a billion times simpler and better known than the sun.
The tides at the centre of the sun don’t matter. The solar cycles and magnetic weather we’re interested in originate in the tachocline or the outer convective layer, or perhaps the surface layer, depending on which theory you read. (I’ve seen both of the first two stated as ‘the way it is’ with absolute confidence.) That’s at most 30% of the way in. And the way I understand it, there’s plenty of ‘sloshing’ going on in the convective layer.
By the way, you may be able to answer a question for me. I found a fair amount of information on the magnetic dynamo – several inconsistent theories each stated as fact, as I said – but was unable to find anything much on the mechanism for the differential rotation and meridional overturn. It’s obviously not like Hadley cells on Earth, which are driven by differential heating, but presumably is due to the combination of convection and centrifugal forces somehow. But the few papers that even mentioned it I couldn’t make sense of, some even reporting the meridional current turning in the opposite direction to others. Do you know of a simple qualitative explanation of the basic mechanism?
Considering the unintuitive way the velocity increases the further you get from the axis of rotation (and if the angular rate is faster at the equator, the velocity must be even more so), this must be a problem fluid dynamicists have paid some attention to. So what’s the answer?
Thanks in advance.
leebert: the percolation theory may not be the right one either [I like it, but we don’t know], but at least it shows that the deep conveyor belt is not something that HAS to be there to explain the solar dynamo.
Leif writes:
MarkW: hasn’t grasped the idea.
———–
From you, that is a high compliment.
Back it down please, civil discussions only~jeez
Steveo: Conflating in the sense that we can have good knowledge about the conditions [composition, temperature, pressure, flows, etc] without being able to put that knowledge to work in a good theory. Do we really have to go over this? I was pointing out that helioseimology has shown us that our theories about the constitution of the Sun were pretty good. You were citing a paper that pointed out that our dynamo theories were not very good. The only conclusion I could draw was that your citing of that paper was a rebuttal of my statement that our ideas about the physical conditions were vindicated. In re-reading your exact wording: “some of the aspects of the solar dynamo that don’t in fact fit theory, and aren’t understood” I must admit that I possibly have imbued them with more sense than was actually present. I thought ‘the solar dynamo’ was the theory. But I may be wrong on this interpretation of your intended meaning and maybe you were not objecting to my statement that helioseismology has largely confirmed what we thought we knew about the physical conditions. Perhaps I simply couldn’t follow your argument. in which case my incapability to do so cannot be ascribed to your conflation of anything.
The current ideas about the differential rotation is that it is a result of the Coriolis force acting on the convection. This does not mean that we have a satisfactory theory of the Sun’s differential rotation. There are fine structure that is not understood. There may be a ‘back-reaction’ of the magnetic field on the rotation, we don’t know. You can find some references and speculation in a recent paper of ours http://www.leif.org/research/ast10867.pdf
Our understanding of the flows is poor but steadily improving. Few believe that millimeter displacements even over years have any effect against the general roiling and chaotic movements in the convective zone. The tidal people try to explain flares on a time scale of minutes by planetary alignments and to predict the appearance of sunspots on certain days, or weeks, etc.
A general problem that I see is the eternal cries: “is it not concievable, that…”, “how can you say it is impossible, that…”, “might it not be some mechanism, that you don’t know about…”, “my gut tells me, that…”, “I just can’t [or worse: won’t] believe that…”, etc. None of these are very helpful.