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## The Rotational Effect

Climate scientists think that the rotation of the earth is responsible for a lot of the atmospheric and ocean effects that we see. In fact, most climate scientists think it is easy to prove. (Although not as simple as proving that radiatively-active gases affect the climate).

Now suppose the earth’s rotation speed was reducing by X% per year as a result of some important human activity (just suppose, for the sake of this mental exercise) and had been for 100 years or so.

Then atmospheric physics papers and textbooks would comment on the effect of the current speed of rotation of the planet – quantifying its effect by analyzing what climate would be like without rotation. This would be just as an introduction to the effect of rotation on climate. Let’s say that the mean annual equator-arctic temperature differential is currently 35°C (I haven’t checked the exact value) but without rotation it might be thought to be 45°C. So we will describe the rotational effect as being responsible for a 10°C arctic-equatorial temperature differential.

More specifically the rotational effect might be quantified as the number of petawatts of equatorial to polar heat transported vs the value calculated for a “no rotational” earth. But by way of introduction the temperature differential is an easier value to grasp than the change in petawatts.

Various researchers would attempt to calculate the much smaller changes likely to occur in the climate as a result of the rotational changes that might take place over the next 10-20 years. They would use GCMs and other models that would be exactly like the current ones.

And of course there would be many justifiable questions about how accurate the models are – like now.

And many from the general public, not understanding how to follow the equations of motion in rotational frames, or the thermal wind equation, or Ekman pumping, or baroclinic instability, or pretty much anything relating to atmospheric & ocean dynamics might start saying:

The rotational effect doesn’t exist

Many of these people would be skeptical about the small changes to climate that could result from an impercetible change in the rotation rate.

Many blogs would spring up with people using hand-waving arguments about the climatic effects of rotation being vastly overstated.

Other blogs would write that climate science makes massively simplistic assumptions in its calculations and uses the geostrophic balance as its complete formula for climate dynamics. Many other people unencumbered with any knowledge from climate science textbooks, or any desire to read one, would curiously label themselves as skeptics and happily repeat these “facts” without ever checking them.

People with some scientific qualifications, but without solid understanding of the complete field of oceanic or atmospheric dynamics, would write poor quality papers explaining how the rotational effect was much less than climate science calculated and produce some incomplete or incorrectly derived equations to demonstrate this.

These scientists and their new work would be lauded by many blogs as being free from the simplistic assumptions that has dogged climate science and yes, finally, accurate and high quality work has been done!

Other blogs would claim that climate science was ignoring the huge effects of absorption and emission of radiation on the climate.

Then some more serious scientists would come along and write lengthy papers to argue that the rotational effect as defined by climate science does not exist because the “no rotation” result is incorrectly defined, or is not possible to accurately calculate.

Papers of incalculable value.

### 38 Responses

1. SoD
Any claimed “effect” needs to be more tightly defined.

For example Hans Jelbring commenting on Tallblokes site recently has said he is happy to call the ‘atmospheric effect’ the ‘greenhouse effect’ since everybody else is calling it that.

Hans Jelbring you will remember has very similar views to William Gilbert.
Both have very similar views to G&T.

Now what point is there in everybody saying they believe in the greenhouse effect when they mean completely different things?

2. Bryan,

Let me ask you a question.

A carjacking took place in Manhattan and the police suspect Z. Jones. The police question suspect Z. Jones who claims he has 3 alibis for the night in question.

Scenario A. The police question the 3 witnesses and all 3 claim he was at a function in Queens that night and they can vouch for his presence.

Scenario B. The police question the 3 witnesses. Witness Smith says that Jones was having a romantic dinner with her at the time in question. Witness Doe says that Jones was playing 5 a side football with him that evening. Witness Blogs says that Jones was having a drink with him in NJ that evening.

Are the police wrong to be skeptical of scenario B?

• SoD

I sometimes use this crime scene analogy too.

I also think of it as an attorney claiming “my client has never been to the place where the murder has taken place. And besides, he did it in self defense.”

As you pointed out before, self proclaimed skeptics never disagree with one another, even if their claims do.

• Alexandre

I take your point on this (and SoD, who mentions it quite frequently) but I think it can be overdone. If I’m presented with an edifice that I think lack foundations (for a particular reason), I’m going to be much less interested in arguing with other people who have a less convincing reason (to me) for the edifice to be unsound, than I am in persuading the edifice-builders that they’ve got something wrong.

There are many ways and perspectives people have for thinking that the full-blown CAGW presented by the likes of James Hansen is unlikely – or just false. I see no reason for purveyors of all these perspectives to form a coherent whole – or even agree with each other.

I think a lot of politically motivated ‘scepticism’ is just bunk. And I’ve spent enough time here and at Climate Etc to be convinced in my own mind that people who dispute, say, ‘back radiation’ are just wrong. But I don’t concern myself with them – or with other unconvincing sceptical views – but I remain very sceptical of the Hansen position.

Why should it be a problem that sceptics don’t agree with each other. Why should we?

• Alexandre/SoD

I think your crime scene analogy doesn’t quite work. With the climate debate, the alibi’s are not less convincing on the grounds that they are competing. I’m afraid you have to take each on its merit. There is no scenario A – there are various alibis – some of which (but not all) contradict others. It surely doesn’t help you to rebut them by saying – look, you disagree with someone else’s argument so I’ll take you less seriously. It may be tedious to be faced with what seems like a mountain of rubbish, but your edifice needs to be immune to every single criticism, or why would you continue to believe it?

• Anteros,

I don’t think there is any requirement for skeptics to agree with each other – or any conclusion that can be drawn from disagreement. If I have given that impression then my apologies.

It is fascinating that many confused skeptics believe contradictory theories and present the multiplicity of (contradictory) theories as more evidence against climate science. Rather than evidence of their own confusion.

But this is no reflection on someone who only believes one theory, or is simply skeptical of a theory in climate science.

• SoD

Fair point. Although they’re not in my usual viewing-frame I’ll readily admit that there are some who will use all/any anti-AGW ‘evidence’ they can find. And I guess they do look pretty funny if you see a lot of them.

The reverse probably isn’t true – I suppose fanatics of the opposite persuasion perhaps simply repeat the same point endlessly irrespective of its cogency.

Not quite as obviously absurd..

• SOD: If Scenario B occurred, it would certainly be wrong for the police to assume that the suspect asked all three witnesses to provide him with an alibi. In that case, the result would be Scenario A. The conflicting alibis suggest that the police should look more carefully at the three witnesses stories and motivations. If two witnesses knew that their close friend Jones was a suspect, but the third witness was a member of the opposing football team with no reason to lie; do the two dubious witnesses cast doubt on the credibility of the third, simply because their stories conflict.

If some skeptics are uninformed and make ridiculous statements, should that color your attitude towards all skeptics? Should the existence of three (or thirty) dubious refutations of GHG-mediated global warming prejudice the scientific rigor with which you analyze the next one?

• Frank,

Similar to the answer to Anteros, “no”.

A few commenters here have the idea that if they add their contradictory beliefs together it amounts to more than one argument “against something”.

Whereas it amounts to a maximum of one argument.

But that doesn’t predicate a judgement against “the next idea” from someone who has only one idea. Or it shouldn’t.

However, and this is just an unfortunate anecdotal history thing, I do find that the “next argument” against “something to do with global warming” is 95% likely to be from someone who hasn’t read a textbook, and has no familiarity with the last 30 years of climate science. In the most recent case, Nikolov & Zeller have been lauded by the internet fraternity for their free-thinking. But honestly, I really don’t want to get past page 5 of their paper, it’s so bad.

A long time ago I tried to learn snowboarding on a “dry slope”. This is really concrete, topped with wire and a little bit of water sprayed on top. What I found was that after falling over for the 50th time, there was a fair bit more fear on my part than the first few times.

In reading the next “great idea” I find some expectation on my part that it will be less than sound. But I cannot claim any “a priori” on this. It is simply experience that means nothing for the wider world. And, like getting back onto the snowboard, I have to work on the basis that the next idea might be “the one”.

In any case, the older argument against AGW is the one that has the most merit – the predictability of climate,

http://www.climate-lab-book.ac.uk/2011/earth-backwards/

About your scenarios. Surely the police should be sceptical about both scenarios given the limited information available..There seems to be multiple possible explanations for how both scenarios may have came about. And both scenarios still seem to encompass the possibility of Jones being either guilty or innocent of the crime.

• HR,

I have started on that topic – see The Coriolis Effect and Geostrophic Motion.

In fact, it was because I was thinking about the topic of the earth’s rotation that I wrote this parody piece, inspired by Kramm & Dlugi’s paper.

I asked myself what is the effect of the earth’s rotation? and can we prove it? and similar questions.

• Scenario B. The police question the 3 witnesses. Witness Smith says that Jones was having a romantic dinner with her at the time in question. Witness Doe says that Jones was playing 5 a side football with him that evening. Witness Blogs says that Jones was having a drink with him in NJ that evening.

… or put it another way. Let’s say Smith is a crazy, deluded bunny-boiler who ‘believes’ she has romantic dinners with Jones every night of the week. And Blogs is an alcoholic who in reality can’t remember who he was drinking with on that night. And let’s also say Doe is accurate in his remembering. Is there any reason why these 3 statements should be grouped together as a single piece of evidence? Is there any reason why Doe’s statement should be undermined by the unreliability of the other two?

• HR,

..Is there any reason why Doe’s statement should be undermined by the unreliability of the other two?

No.

But the credibility of someone who claimed that there was multiple independent support for Z. Jones innocence would be undermined.

Which was my point.

• There may be truth in all of this but one thing is for curtone, one of the actions Z. Jones is accused of is true, so whey not all of them. He could of stole the car, when to dinner followed by football well drinking. All thing are one and one is all things.

3. I think you would find that G&T would not be in the slightest agreement with W. Gilbert, even though he wrote:

I was immediately amazed at the paltry level of scientific competence that I found, especially in the basic areas of heat and mass transfer.

Because it turns out that the reason he was amazed was because climate science had to use “calculus” to calculate the adiabatic lapse rate whereas he simply equated pV with pdV (dropped the inconvenient “d”) and solved it the Panama Canal way.

So what Gilbert thinks is totally irrelevant. Jelbring apparently is happy with Gilbert so is equally irrelevant.

What exactly do you think these two people have to offer to a scientific debate?

• The common ground between G&T and Hans Jelbring and William Gilbert concerns the greenhouse effect.
All four doubt that it exists as commonly understood.
Yet Hans Jelbring seems to be quite happy to call the thermodynamic derivation of the adiabatic lapse rate ‘the greenhouse effect’.
One other commentator explained to me that his definition of the greenhouse effect was the difference between the Earth with and without an atmosphere.
He would not quantify the effect however.
Joel Shore on the other hand cannot understand the effect without its full 33K claimed value.
So the point I was making is that to ask someone if they believe in a greenhouse effect is almost meaningless unless you specify the essential features of theeffect

4. on January 11, 2012 at 2:34 pm | Reply Climate Watcher

So, I was waiting for the rotation effect.

Somewhere in my readings I ran across a calculation of the effect of dam building.

Turns out dam building redistributes a calculable though negligible amount of mass to a higher elevation. This in turn reduces the rotation rate of earth.

The effect means days are some fraction of a second longer than they were a hundred years ago.

Is that in the reconstructions?

5. SoD – I was tracking your story/allegory all the way through the last paragraph, but was not able to understand what you were referring to there. For the benighted among us, can you be more explicit in the comments (the post was so well written I would hate to ruin the artistic effect there).

• purgatus,

Any quantification of the rotational effect could be subject to the criticism that the “no rotation” situation is unknown and as the climate would be very different, no one can be certain of its exact value.

This criticism would be a valid criticism. But this doesn’t prove or even imply that the rotational effect doesn’t exist.

If I can’t measure your exact weight do you have no mass?

Papers like Scrutinizing the atmospheric greenhouse effect and its climatic impact, as explained in Kramm & Dlugi On Dodging the “Greenhouse” Bullet appear to take this approach.

6. As anaolgies go, it’s a decent analogy. But like all analogies, it suffers from subjective decisions about what to include, what to exclude, and what to highlight.

For instance, in order for the analogy to be more accurate, the earth would need to be subject to external forces outside anthropogenic control; some of these forces would retard the rate of rotation and some would increase it.

We would know that the earth had spun much faster (and much more slowly) in it’s past, and we’d know that the rate at which it flipped between these two states was sometimes very rapid, and that the proxies we used to determine this information did not have sufficient resolution to allow us to be able to draw conclusions when comparing historic changes with those changes in the century or so we want to consider.

The corrections go on and on.

The argument – and I don’t doubt it’s honestly made – seems to be that we can compare a far simpler scenario with a much more complex and nuanced one, and draw conclusions/

We can’t: the analogy be definition is only an approximation to reality that omits many details. And the Devil etc. etc. etc.

• Korzybski: “The map is not the territory” True, but maps are still useful approximations. Which is Box’s point: “All models are wrong, but some are useful.” If you couldn’t make simplifying assumptions when looking at a problem we’d probably still mostly be farmers using mules or oxen to plow our fields, if we were lucky.

• I don’t accept that the article is a model of anything, certainly not in the sense that it can be tested against any objective truth or empirical data. The best I can stretch it to is that it’s a model of some perceived social behaviour, but that interpretation also has problems.

Similarly I don’t accept that the article is a general discussion on the usefulness or otherwise of models.

“All models are wrong, but some are useful” is a point I certainly agree with, but that isn’t the point of this article and I believe you’ve misinterpreted.

Could you explain why you believe you haven’t?

• Analogies prove nothing, they are simply (intended as) useful illustrations.

I am trying to prove nothing by this article. I am just painting a picture.

Some might find it a useful perspective.

• And I deliberately avoid using the terms “proof” or even “evidence” in my response.

But my point is this; the choice of analogy and the simplifications we choose to embrace in an analogy will inevitably filter out detail we consider irrelevant.

I can infer things from the tone of the article and your closing comments, but I’d rather not; can you be more explicit about the conclusions you’re inviting?

• Mrsean2k, did you read the preceding two posts to this one? If so I think what can be inferred makes more sense..

7. SoD,

“Then some more serious scientists would come along and write lengthy papers to argue that the rotational effect as defined by climate science does not exist because the “no rotation” result is incorrectly defined, or is not possible to accurately calculate.

Papers of incalculable value.”

Warning! Irony and sarcasm are inherently ambiguous. Somebody is always going to miss the joke.

8. Don’t forget to inject doubt and uncertainty:

“I’m afraid damage has already been done to your theory of AGW-rotation.
An eminent philosopher (http://en.wikipedia.org/wiki/Mach's_principle) has already established, which Einstein called Mach’s principle: that the rotation is affected by the distribution of mass in the universe. We all know there is great uncertainty about this and therefore until we know the exact nature of dark matter/energy, it’s distribution and dynamics; we aren’t in any position to attribute rotational change of the earth to human action.”

I even got a “Einstein said…” in there, so it must be true.

9. I thought there realy was a rotational effect. Ice melting at the poles distributed over the world gives a slightly slower rotation, like the skater spreading her arms after a spin.

And the thermally expanding ocean gets the mass away from the centre of rotation

10. SOD: Your rotation analogy may be better than you imagined when your created it. No rotation is a lousy model for illustration what will happen if rotation slows. If some persist in illustrating the problem of slowing rotation using an inappropriate no-rotation scenario, that would increase my doubt their judgment about slowing rotation. The 33 degK calculation is an extremely poor model, so let’s admit it and move on. Arthur Smith did calculations for a number of other scenarios in his comment on G&T (which I haven’t read thoroughly). Let’s see if any of those scenarios are convincing.

AGW doesn’t need a dubious “greenhouse effect”; as Leonard Weinstein noted, there is a perfectly sensible non-controversial explanation involving a rising critical emission level.

Furthermore, Lacis published a paper in Science using the GISS AOGCM model to determine what would happen if all of the carbon dioxide were removed from the atmosphere. (It got a lot colder and cloudier.) If one wants to know if carbon dioxide makes the world warmer than it would be without it, this appears to be the best answer.

11. SOD wrote above:

“A few commenters here have the idea that if they add their contradictory beliefs together it amounts to more than one argument “against something”.

According to standard logic, the probability of A OR B being correct is the probability of A plus the probability of B minus the probability of A AND B. (Similar, but more complicated expressions are available for three or more events A, B , C ….) When A and B are mutually exclusive, the probabilities add and when they are relatively low probability (<20%), they come close adding. (The same is true for multiple events.) The real issue is likely to be that skeptics may consider the probability that hypotheses A, B or C (or more) could refute AGW to be on the order of 10% each – which adds up fast – rather than the =<1% that you may consider more accurate. Studies show that human intuition about probability is fairly bad.

There is a problem if "lukewarmers" add probabilities. If two mechanisms (cloud feedback and water vapor feedback) might independently have a 20% chance of being wrong and reducing the IPCC's predicted warming for 2XCO2 of 3 degC by one degree, there is a real possibility of holding warming to 2 degC (still dangerous in the long run?), but little hope that warming will be only 1 degC.

Finally, there is the massive problem of propagating errors from WG I to WG II to WG III. Suppose bias is keeping an unnecessarily high end to the IPCC's 1.5-4.5 degC/doubling range for climate sensitivity. Suppose WG II finds damage is proportional to 10^T (where T is the temperature change), but mostly ignores adaptation. Suppose WG III underestimates the value of money over time (discount rate) and the cost of alternative technology. I can easy imagine an error of more than an order of magnitude in how much society should invest today to avoid paying more later. The probability that these biases exist in the IPCC's core writing team is high because new authors are selected by the existing team without any requirement for diversity of viewpoint.

• Exactly!

Which is why one of my themes has been that WG-II and WG-III is where the effort of skeptics should be concentrated. Have you ever looked at the details of the SRES like A1B? Most of them don’t look very plausible to me.

I’m not convinced that 2 C warming is ‘dangerous’. It depends entirely on how different regions change and GCM’s have zero skill at the regional level. The idea that droughts will be more severe and last longer in a warmer, probably wetter overall, world is not necessarily true. We should be adapting to risks that already exist, like severe weather, rather than spending vast amounts of money to keep those risks from increasing slightly, if at all while ignoring the plight of populations that are already at risk.

• DeWitt: Why is the starting point for 2 degC of warming chosen to be the poorly known conditions that existed before the start of the industrial revolution and at the end of the LIA? Why not use 1960-2000 as a baseline? In the US (away from the coast), one degC of warming is geographically equivalent of moving 100 miles to the south.

IMO, the observationally-based “science” in WGII and WGIII is far less appealing than the harder sciences, with theories tested by reproducible, controlled experiments. Besides, WGII and WGIII depend on the output from AOGCMs and the discrepancies between observation and prediction belong in WGI. If AOGCMs are close to being correct, significant restrictions on global CO2 emissions probably make sense.

• DeWitt Payne,
While I don’t disagree with your comment, it masks a subtle shift in emphasis from physics/chemistry to adaptation/economics and thence politics. I, for one, will not vacate the space occupied by my objections to the skill of climate models. I want to see some significant predictions be realised.

12. The rotational effect is very pronounced here.
This is a new paper paper by Nikolov and Zeller
Posted on Tallbloke.

I link it here ONLY because of the temperature /time graph of various locations on the Moon.

Eyeballing the graph and by removing the middle 27 Earth day periods we get an almost horizontal (little temperature variation) plot.

The explanation of the Holder inequality is worth a look