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Come on arc, if you are debating with someone and you wish to move onto a new subject then simply move on to the new subject. What you should not do is to quote your opponent on subject (A) and then proceed to talk about subject (B). It makes it look as though you were responding to subject (A), which is confusing. Now if you wish to talk about Doglioni and his work then I'm happy to move on to subject (B). (It is in fact far more interesting to me than subject (A). ) The apparent net westward rotation of the lithosphere (known about since at least Le Pichon 1968 and the basis of Doglioni's work) remains problematic which is, no doubt, why you have seized upon it. I would counter your request for an explanation by reminding you that nobody has claimed convincingly to have fully explained the dynamics of plate tectonics. (Except for you of course! ) The dynamics of plate motion remains perhaps the greatest unsolved challenge in Earth sciences today. From the observations outlined in Doglioni [2003] of net westward lithospheric rotation it follows that the lithosphere must be partially decoupled from the underlying mantle and this decoupling is accomodated in the asthenosphere. The very nature of the lithosphere asthenosphere boundary remains a great unsolved challenge which inhibits progress. Around subduction zones it is estimated that the asthenosphere can displace particles around 8 times faster than the overlying lithosphere, and it still remains unknown to what extent the asthenosphere decouples from the lithosphere upon subduction. There are many many unknowns (e.g. mechanical parameters, thermal parameters, water content, etc.) which makes it incredibly difficult to model these things with confidence. It remains for more reading to be done (by myself and whoever else out there feels they can contribute) to see if anybody has ever successfully modelled net westward rotation, but I suspect not. (I am aware of workers who have used it as an input to their models, but these are models inverted from data, I am more interested in a model built from first principles that predicts this behaviour.) Of course, seeing as your model is so powerful, perhaps you could enlighten us on how your model produces the net westward lithospheric rotation ... What does seem clear though, if we look at the big picture, is that plate tectonics is a conveyor belt for the Earth to lose heat. By continually creating hot new crust, letting it cool down and then swallowing it back down again for it to be reheated, and repeat, the Earth is shedding its heat. It is inescapable that this very process is intrinsically a part of mantle convection. This is compounded by the strong body of evidence that slabs penetrate through the transition zone all the way down to the core mantle boundary. So when I say we do not understand the dynamics of plate tectonics I am being quite precise, it is clear however if we take squinted eye view that overall mantle convection is central to plate tectonics.

Whoa arc! hold on to your hat cowboy, you've seriously gone off the rails. I was talking about convection currents in the outer core in relation to the geodynamo. You are talking about something quite different: mantle convection. This leads me to wonder if you actually read my posts at all?

Hi arc, There does appear to be a weak solar forcing on the strength of Earth's magnetic field. This is reflected in the delta carbon-14 records. A leading group of scientists who reviewed existing data have concluded that this forcing is too weak to explain the current global warming trend. "Changes in Solar Brightness Too Weak To Explain Global Warming" (Press release). UCAR. 13 September 2006. Retrieved 18 April 2007. What appears to be true though is that perturbations of amplitude about 0.1% in the solar intensity manage to affect Earth's magnetic field just enough to change the number of cosmic rays that enter the atmosphere and that this effect is detectable by careful study of delta carbon-14 ratios. You are taking this and projecting it into the extreme. What you are proclaiming as that these minor fluctuations are also responsible for thermal expansion and contraction of the outer core -- which in turn explains the driving mechanism of plate tectonics!!!!! (Wow, just wow!) In your mind the Earth's magnetic field (and apparently the magnetic fields of other planets) would not be able to exist without these "kicks" from the Sun (which I remind you are very slight in amplitude). Because apparently you cannot "see" how a magnetic field would survive on its own. But this is ridiculous! I can't "see" how a caterpillar morphs into a butterfly -- but that doesn't make it less of a fact. What's more .. the very workers you cite (Glatzmaiar and co) have shown exactly what you cannot see! They've laid it out for you -- just read and learn! The magnetic field is driven by the continued formation of the inner core. As the inner core freezes latent heat is released and light elements are expelled. This produces convection currents which are aligned by Earth's spin into columns parallel to the rotation axis. This dynamism produces the Earth's dipolar field in the familiar way.

Hi arc, I still don't understand why you pick out Glatzmeier's model. In fact it is direct contradiction to what you are saying. I have emphasised in bold your own words above. "I see a planet that has maintained heat content and a magnetic field far beyond the expectations of the physics known to be involved." But surely that flies in the face of Glatzmeier's work. He has used the known physics incorporating geophysical constraints to model a geomagnetic field with the time varying properties similar to those found in the palaeomagnetic record. In other words he has shown exactly the opposite of what you said: a planet that has maintained heat content and a magnetic field in complete agreement with the expectations of the physics known to be involved. This is surely a fine example of why intuition can be a treacherous guide in science.

Hey StringJunky, I don't believe I have argued from authority, i.e. I have never said I am right because I have qualifications x, y, and z. In fact I never even mentioned the PhD until just now. My argument has always been that arc's theory is very very probably -- indeed almost certainly -- wrong. Now I understand that that may sound arrogant. But I have justified my stance using reasoning. 1) Physical reasoning. Consideration of the energy required to induce the large volume changes in the liquid outer core seem to render the theory impossible. 2) Russel's teapot. Or the giant ant hypothesis. Or the flying spaghetti monster. I can make up a shed load of random crap that nobody will ever be able to prove wrong. Especially if my theory comes in the shape of a cartoon with edges that can be moulded to fit the facts in an ad hoc way. My problem (in case you hadn't already guessed) is that this approach is unscientific. 3) The seemingly random use of references complete with giant leaps of faith necessary to follow the theory. Again unscientific. Of course I would be very happy to see some science done, and then if the theory still stands up then I would relax my stance a little. The problem of the dynamic mechanism behind plate tectonics is one of the great unsolved challenges facing earth sciences today. This is why the topic attracted my attention. I am genuinely interested in finding the solution.

Studiot, I intended to address this post and apologise for the lateness of my response. With regards to the opponents lack of humility. I must say I admire your patience and your high level of humility, but that is your style. I do not believe in humility for its own sake. If I think I know better then I will say that. I believe I am qualified to give a weighted opinion because I have been a student of geophysics for over a decade. I am currently near completion of a PhD thesis in geophysics which has a focus on seismically probing mantle deformation. I have worked with data types that most here probably do not even know exist. I read many papers, and do so critically. That's why when I read arc's work it is obvious to me that it is little more than a stab in the dark. For example, he repeatedly shows the figure of Glatzmeier's magnetic field, but it is entirely unclear to me how Glatzmeier's work supports his theory, other than the incredibly tenuous link that Glatzmeier has modelled the field getting weaker with time. (So what??) That is something we knew way before Glatmeier cam along, from actual observations, so why use Glatzmeier's model? One suspects it is because of the pretty picture. Such sloppy usage of references is typical and is reflected by the sloppy logic that ties the elements of the theory together. If he is correct then he will have to try a lot harder to convince me. He could start by actually responding to my earlier criticisms without copying and pasting from his blog.

Well someone needs to say something to pump blood into this thread again. I keep checking back to see how the ground work of my field has been shattered but there has been no progress. Otherwise I suppose we could just let the theory die. But what's the fun in that?

I would like to add my voice to that. Quoting is problematic (Safari user here). I have had two problems, both specifically related to the fact that when you edit a reply the quoted text is "locked in a quote box" and I cannot seem to edit the tags: 1) sometimes I'll be trying to delete some quoted text from the top of the quote and if I accidentally backspace when the cursor is right at the beginning, then the server sends me back to the thread and I lose all my reply. (frustrating!) 2) I wanted to break up the quote into separate boxes and put some of my own text in between. It just wouldn't let me because i couldn't put the tags where I wanted them.

Also he thinks a joule is a watt per second.

1) Really? If I'd known the Sun was a star then that would have changed EVERYTHING! * on a more serious note -- you might want to check out this pretty cool thing called the inverse square law. 2) Sure ** digging around ** it's here: http://onlinelibrary.wiley.com/doi/10.1029/2011GL047450/abstract ps - thanks for the down votes

Arc, it looks like you're squirming and back tracking here. If in your model the earth radius does not change then how exactly does your model work? Remember you're claiming to have a dynamic mechanism here, and I just don't see any dynamics with a constant radius earth. This is another blow. Any claim that your model is simple has vanished. Remember Occam's razor?

Woah!!! Of course if you assume that 100% of the Sun's power output goes into heating the core by a 100% efficient mechanism then yes, it appears we do have rather a lot of energy available to do magical things. But if you assume the above is valid then you must be living in a different universe! There was a paper release about a year or so ago that used satellite data to look for evidence of Earth expansion. Not surprisingly they did not find any (I'll dig out the paper if you're interested). I do not feel very comfortable talking about the magnetic torque effect (I'm a seismologist). But bear in mind that unless the Earth's mantle contains significant conductive material it is hard to exchange momentum between the solid earth and the magnetic field. EDIT: of course an expanding and shrinking planet would change the moment of inertia, this would hence change the rotation rate, much like an ice skater controlling the speed of their pirouette by bring their arms in/out.

A minuscule volume change would be unnoticed at the surface. It is a giant leap of faith to say that it would "cause plates to act in the fashion that they do". After much pressing arc finally gave me the number of ~ 80 km (post #119).

Arc, I notice you still have not addressed the large volume change necessary in your model, and have been notably silent on the question of energy budget. I'm glad to see other users pressing you on these matters and hope you will begin to take them with the seriousness they deserve. One first would like to note the irony of your attack on the ad hoc theories. Your model requires quite strange ad hoc adjustments to explain how expansion and contraction tectonics can take place simultaneously. But what is "plume theory"? Are you talking about the attack on the existence of mantle plumes and the big debate that raged at its peak five to ten years ago fuelled mainly by Don Anderson and Gillian Foulger? What is the significance of that debate here? As far as I am aware, it was once suggested in a famous paper by Jason Morgan that plumes might be the driving force behind plate tectonics. But that was over thirty years ago and nobody seriously believes that anymore. Plumes are simply a mode of mantle convection. Subduction can be seen as another mode of convection -- a mode of convection far more important for plate tectonics. One does not require the other. If we have a debate about plumes we would be missing the point. Again, I do not understand what you intend to mean by "plume theory" but please read what I wrote above about that. I certainly do not take any credit for the development of "plume theory". The ants were obviously meant as a satirical swipe at your theory. It was aimed at all those who remain agnostic about your theory -- (let's wait it might turn out to be right -- but I'm not sure). It's a "Russel's teapot" argument: yes there might just be a teapot orbiting the Earth, but actually in all likelihood there isn't. There might just be a colony of giant ants driving plate tectonics -- but in all likelihood there isn't. There might just be a core swelling up and shrinking with volume changes in the region of 30%, driven by heretofore unheard of million odd year solar cycle, which somehow quickly heats up and cools down the outer core by some vague mechanism (it must be quick because otherwise the heat would be leaked and the temperature would not rise) -- but in all likelihood there isn't.

Unity, The plates moved because there is a giant ant colony living in the mantle and they carry the plates on their backs. They live about 200 km deep and eat their way through the mantle material. They are evolved to withstand the tremendous pressure and temperatures found down there and never come up to the surface which is why we don't see them. They eat through the mantle leaving behind a soft residue thus -- my model predicts the existence of the asthenosphere -- this is a simple, accurate prediction not made by any of the competing theories. They converge at subduction zones to mate, and this process drags the plates behind them opening up rifts forming the new oceanic lithosphere. Now I open it up to the floor for someone to PROVE my theory wrong. Until it has been proven wrong please give it the respect it deserves and treat it seriously. I have not done any number crunching here, but I have provided the skeletal framework for how the Earth works and have completely laid the groundwork for future generations. I believe my contribution to the field is complete. I leave it to others to fill in the details. My theory must be right because it is simple (note to self: insert patronising link to Occam's razor). My theory will be ignored by many experts but this is what happens when a genius like myself steps onto the scene from nowhere and shakes things up, I'm rather like the Einstein of the earth sciences and there will be people who will not like it. This is actually why my theory cannot be published, because it is being suppressed by the aristocracy who wish to hang onto their thrones.

Arc, given your lack of response to my serious criticisms of your theory (post #146), are we to take it that you have admitted defeat? To any readers who still have their doubts that the theory is debunked. If a theory requires extremely elaborate basic physics, of the likes never seen before, just to reconcile it with the basic geometry -- what is the likelihood that the theory is correct? Add the fact that the theory has seemingly come from nowhere, based entirely on the intuition of a non-expert. (Human intuition is a notoriously bad guide for discovering nature -- cf quantum mechanics.) What now are the odds that theory is correct? One in a million? One in a billion? One in a trillion? This is a theory that is supposed to explain plate tectonics, but the theory has so much missing. For example I have not seen a single sentence that explains how this theory explains the kinematics of plate movement. That is the fundamental tenet of plate tectonics, that the plates move in solid body rotations about Euler poles. And there is a wealth of evidence to show that this theory holds, at least to first order. All of this is simply ignored in this theory. Now what are the odds that this theory is correct? One in a quadrillion? Basically the chances of this random theory being correct are about as high as any old theory that you or I could make up tomorrow after a couple of pints in the pub. It's good for a laugh but that's about it.

Arc, you are really unbelievable. Let's review the timeline: 1) I asked you for the change in Earth's radius needed for your theory. 2) you gave the number 500 km (+ a load of incomprehensible waffle.) 3) I used the number 500 km to show that the required change in Earth volume to account for this radius change was greater than the volume of Earth's core. i.e. your theory fell through the ground. 4) you then stated that actually the 500 km was for the circumference change in Earth, NOT the radius! (even though that was not what I asked for) 5) I got a bit peeved that you couldn't answer a simple question with a straight answer and "admitted" that I was "mistaken" (I would rephrase that to: I conceded that you might have actually meant the circumference rather than radius and perhaps you got confused and perhaps made an honest mistake, and therefore I would need to revisit the numbers.) 6) I revisited the numbers -- this time using the 500 km as the CIRCUMFERENCE of the Earth and found that the core would need to DRAMATICALLY change its volume (shrinking by 25% at a conservative estimate). 7) You sweep away my criticism with the above remark. WHAT DO WE LEARN? Either you don't know the difference between the radius and the circumference of a circle, or you are succumbing to the logical downfall of your argument and you have nothing left to do but use diversion tactics. Have you ever considered the possibility -- for even a second -- that you might be the one who is wrong? Clearly! Comparing yourself to the likes of Newton and Darwin. You do realise this is absolutely classic, this will launch you way up the crackpot index.

UPDATE: I stumbled upon an interesting sentence in a paper while doing some reading: R J Stern (2002), Subduction zones, Rev Geophys. So arc, please, check your facts.

OK so 500 km of circumference, just for fun let's consider the geometry of this. According to my calculations you need to contract the core volume by 25% its present volume to account for that kind of circumference change. That is HUGE! So your task now is to calculate the temperature changes needed to invoke this kind of volume change through thermal expansion. How much energy would this take? What would happen to the inner core? Would it not need to freeze and melt? Where is all this energy coming from? First off I haven't independently checked that there really is half the length of convergent margin as there is divergent margin. Let's assume you're right for now. This implies that per unit of length an average convergent margin (trench) swallows up twice the volume of material being produced at the average divergent margin (ridge). Or if you prefer there are two ridges doing the work of one trench. At first glance this does seem weird, but it is not inconceivable that there could just be lots of "slow ridges" bringing the ridge average production down. That would account for it. Now it is your job to prove that there really is a problem. Or as you put it "a discrepancy". You cannot just throw out words like "technical", "accurate","clear", "discrepancy". They do not convince scientists. Scientists prefer to see data. I'll give you a recipe for what would convince me there is a problem: (1) take a recognised database of plate boundaries (2) take a recognised model of plate motion (a good one would be HS3 NUVEL 1a (Gripp and Gordan 2002)) (3) integrate the convergent plate motion along the length of all convergent margins. (4) integrate the divergent plate motion along the length of all divergent plate boundaries. (5) show that they do not balance. That would probably be a day's work for me. (i.e. something I'm not prepared to do when I have real science that needs doing for publication in real journals.)

1) So it must be right then? 2) The truth is the truth. We just believe what we want to believe. Some of us look harder for the truth than others before we settle.

Yawn. Arc, if you had simply answered my question *with a straight answer* all this would have been avoided. I'm afraid I can't keep up with your ramblings. My misinterpretation of your number may make the geometrical argument invalid, but let's be clear -- you're still wrong. At the end of the day I say this ... believe what you want to believe ... I for one am in search of a more believable truth.

Arc, You seem like a nice person, but your science is fatally flawed. This is exactly the problem: How do you justify that "no maths [is] required". Surely if you want to TEST your theory you need some model to compare against observations. What you have done so far is come up with a paradigm framework, and are filling in the details with cartoons. This does not mean necessarily that the paradigm you have is wrong, but any cartoons you draw from it are just that -- *cartoons* -- and cartoons do not amount to anything scientific at all. Therefore you have NO evidence in support of your theory. So it leads me to think that in all probability your *idea* is wrong. Not just because there is no firm evidence beyond some random guy on the internet's cartoons, but because it seems to defy thermodynamics and simple geometrical considerations at once. Let me entertain you with the ridiculousness of the geometry here: You are claiming a radius change in the Earth of about 500 km. Let's put some numbers where you failed to do so and say that the minimum and maximum radius of the Earth is 5900 km - 6400 km. What is the volume change between these two states? Simple spherical geometry tells us it is about 2.4 * 10^11 km^3. Now your theory requires that this volume is accommodated by expansion and contraction of the core. But hang on *alarm bells* the volume of the core is only 1.8 * 10^11 km^3 (when the Earth's radius is near enough 6400 km )!!!!!! So even if the core completely disappeared (including the inner core) -- the Earth would not contract enough to meet your theory. ooops

Arc, Thanks for giving the most honest reply you could. Based on the fact that you cannot answer a simple and fundamental question, it is evident to me that this theory is not ready, and in all likelihood is false. I kindly advise you to stop wasting your time on this theory. Why? Because: • the theory is no better in any way than the current theory • the theory is worse in many ways to the current theory (not least that it requires a complete development of a mathematical physical model -- i.e. it's current status is "cartoon" -- whereas workers e.g. Paul Tackley have successfully produced plate tectonic Earth's in numerical simulations without the need to invoke your "mechanism".) The list could go on ... Lastly, if you are intent that your theory is right, I suggest you get it published in a peer reviewed journal. Only then will people sit up and take notice. •

Hi Ophiolite, Spot on. If my simple question cannot be answered directly then it will be clear that arc has not thought through his idea thoroughly. This would spell the end of my interest in the thread. Here's hoping for a straight answer.

Arc, Please answer my question: Can you please tell us the range in Earth's radius required to explain all the observations. Earth's present radius is approx 6371 km. To be clear I want to know what Earth's radius would be at maximum contraction and maximum expansion according to your theoretical model. A brief and direct response would be appreciated.