Home/BlogNOTE: I am making available the Excel spreadsheet with the simple forcing-feedback-diffusion model so people can experiment with it. The spreadsheet is fairly self-explanatory. THE DIFFUSION COEFFICIENTS CANNOT BE VARIED TOO DRASTICALLY SINCE, WITH A MONTHLY TIME STEP, THE MODEL WILL CREATE UNSTABLE TEMPERATURE OSCILLATIONS. This is a common problem with numerical integration, which could be eliminated by reducing the time step, but I wanted to keep the model file size manageable:
simple-forcing-feedback-ocean-heat-diffusion-model-v1.0
FOLLOWUP NOTE: The above spreadsheet has an error in the equations, which does not change the conclusions, but affects the physical consistency of the calculations. The heat capacity used for water is 10 times too low, and the diffusion coefficients are also 10x too low. Those errors cancel out. I will post a new spreadsheet when I get back to the office, as I am on travel now.
NASA’s James Hansen is probably right about this point: the importance of ocean heat storage to a better understanding of how sensitive the climate system is to our greenhouse gas emissions. The more efficient the oceans are at storing excess heat during warming, the slower will be the surface temperature response of the climate system to an imposed energy imbalance.
Unfortunately, the uncertainties over the rate at which vertical mixing takes place in the ocean allows climate modelers to dismiss a lack of recent warming by simply asserting that the deep oceans must somehow be absorbing the extra heat. Think Trenberth’s “missing heat“. (For a discussion of the complex processes involved in ocean mixing see here.)
Well, maybe what is really missing is the IPCC’s willingness to admit the climate system is simply not as sensitive to our greenhouse gas emissions as they claim it is. Maybe the missing heat is missing because it does not really exist.
This is where we can learn from the 40+ year record of deep ocean temperature changes. Even the 2007 IPCC report admitted the oceans have warmed more slowly at depth than the climate models can explain.
Here I will show quantitatively with a simple forcing-feedback-diffusion model that recent ocean warming is actually consistent with a climate sensitivity which is so low that the IPCC considers it very unlikely.
I will also show how disingenuous the IPCC 2007 report was in presenting the ocean warming evidence to support its view that anthropogenic global warming will be a serious problem.
The Need for Ocean Layers in a Climate Model
Ten years ago Dick Lindzen used a simple climate model to look into the issue of whether the rate of ocean warming at 500 meters depth might help us better understand how sensitive the climate system is. He concluded that it is the surface temperature that is most important, not what happens deeper down in the ocean.
Conceptually, the line of reasoning here would be that the deep ocean can’t warm unless the surface warms first, and the rate of surface warming is largely controlled by atmospheric feedbacks.
In contrast, Roger Pielke, Sr. has always maintained that the heat content of the ocean is what we should be monitoring, not the surface temperature, to better understand how sensitive the climate system is to various forcings.
I WILL say I firmly believe that the surface temperature is THE MOST important temperature in the climate system. This is because (1) the surface is where most sunlight is absorbed, (2) the atmosphere is then convectively coupled to the surface, and (3) the surface and atmosphere together are the ONLY way for the Earth to radiatively cool to space in the face of continuous solar heating.
But, as we will see, the detailed profile of recent warming with depth in the ocean does appear to have additional information about climate sensitivity that is not apparent from surface warming alone.
Explaining the Observed Heating Profile of the Ocean
The following picture is worth a thousand words….but I will try to use fewer than that. First, it is partly a reworking of Fig. 9.15 of the IPCC 2007 report, showing the substantial discrepancy between observed global-average warming of the oceans to 700 meters depth (red curve), and warming estimated from the PCM1 climate model (solid green curve) for the 40-year period ending (I believe) around 2005 (click for the large version).
The green dashed line is my simple model simulation of the PCM1 model’s 40-year warming profile, where I used the GISS yearly global climate forcings to force temperature changes in the 30-layer model, where all layers have adjustable diffusion coefficients.
To get this match to the PCM1 model results, I specified the known PCM1 model net feedback parameter (1.8 Watts per sq. meter per degree), and then adjusted the diffusion coefficients between the simple model’s 50-meter thick layers extending from the surface to a depth of 1,500 meters until I got good agreement between my simple model and the PCM1 model results.
As you can see, my model fit (green dashed line) to the PCM1 model results (green solid line) is pretty good. (Some small amount of warming occurs all the way to the 1,500 m bottom of the model, although it is extremely weak). This demonstrates that the simple model can basically replicate the behavior of the much more complex PCM1 model, albeit for only global-average results.
Next, after I got the simple model to mimic the PCM1 model, then I tried to explain the observations (red) curve by adjusting (1) the model sensitivity (assumed feedback parameter), and (2) the diffusion coefficients, until the model explained the actual observed warming profile. Interestingly, the diffusion coefficients only needed to be changed for the top three ocean layers (down to 200 m depth, which would be about the bottom of the themocline.) The rest of the diffusion coefficients remained the same as in the PCM1-matching simulation.
The result is the blue curve. Significantly, the simple model required a feedback parameter equivalent to a climate sensitivity of only 1.3 deg. C in response to a doubling of CO2. This is well below the range of warming the IPCC claims is most likely (2.5 to 4 deg. C).
What It Means
The bottom line is that 40 years of warming of the 0-700 meter ocean layer has been so modest that, even if we assume it was caused by the GISS forcings (which Hansen believes will eventually cause strong warming) , it corresponds to low climate sensitivity anyway.
In other words, the oceans have not warmed enough to support the IPCC’s predictions of future warming.
The problem in the IPCC models seems to be that they mix excess heat too rapidly from the mixed layer into the deep ocean. This allows the models to retain high climate sensitivity, while limiting the amount of surface warming they produce to match the observed warming to date.
Voila! The models can thus “explain” the surface temperature record AND STILL predict strong warming for the future.
Even though the model I use is admittedly simple, this does not really matter because, in the global average, long-term temperature change is only a function of 3 basic processes:
(1) the strength of the forcing (imposed energy imbalance on the climate system, due to whatever);
(2) the strength of the climate system’s resistance to that forcing (net feedback, which determines climate sensitivity); and,
(3) the rate of ocean mixing (which affects surface temperature, which affects the rate of energy loss to space through feedback processes).
Everything else is details.
How the IPCC Cheated
In the process of this little study I learned that the IPCC’s 2007 presentation of the ocean warming data was, at best, disingenuous. Here’s the original PCM1 panel of Fig. 9.15 from the 2007 IPCC report, from which I took numbers to re-plot on the figure, above:
With this figure, the IPCC was cleverly able to make it LOOK like there was general agreement between their climate models (green shaded area) and observations (red curve), with no less than four ploys:
1) They chose a climate model (PCM1) that is the 2nd LEAST sensitive of the twenty-something climate models they survey. PCM1 produces even less warming than the IPCC’s official projected range of warming from a doubling of CO2.
2) For the PCM1 model results, they presented a rather broad range of warming (green shaded area), meant to represent natural climate variations about the average warming produced by the model. In this way, they were able to get the weak observed warming to better overlap with the model produced warming, suggesting agreement.
3) They omitted the 0 deg. (no temperature change) vertical line from the figure, the presence of which would have visually revealed the significant discrepancy between the PCM1 model results and the observations.
4) They made the ocean depth scale nonlinear, which disproportionally emphasized the agreement in the relatively shallow mixed layer of the ocean, while downplaying the rather large discrepancy deeper down. But there is NO physical reason to make the ocean depth scale nonlinear; the total heat carrying capacity of the ocean varies linearly with depth, not non-linearly.
Conclusion
It appears that the vertical profile of ocean warming could be a key ingredient in getting a better idea of how sensitive the climate system is to our greenhouse gas emissions. The results here suggests the warming has been considerably weaker than what would be expected for a sensitive climate system.
The sensitivity number I estimate — 1.3 deg. C — arguably puts future warming in the realm of “eh, who cares?”
It will be interesting to see how the next IPCC report, now in the early stages of preparation, explains away the increasing discrepancies between their climate models and the observations. Since IPCC outcomes are ultimately driven by desired governmental policies and politicians, rather than science, I’m sure the wordsmithing (and figuresmithing) will be artfully done.
IMPORTANT NOTE: The above model simulation does not account for the possibility that some of recent warming could have been due to one or more natural processes, in which case the diagnosed climate sensitivity would be even lower.
Excellent. They the (IPCC) are full of it. I will be posting the secondary effects , I expect from this prolong solar minimum ,and how it may increase earth’s albedo, when the June temp . data comes out.
take care
Dr Roy
Thanks for making your work available to the public.
This is an excellent demonstration. I hope that you will consider putting it into publication or in lieu of that, putting the code/data on line so that us non-pro’s can mess around with it. I would be interested in seeing how the math was done either way.
It is especially interesting considering the numerous posts done on climate blogs lately which have matched global model averages with very simplified equations.
Jeff, I indeed would like to put the model out there so others can play with it. It runs in an Excel spreadsheet. I just need to clean in up and put some explanatory notes in it…and maybe extend it down another 1000 meters.
But this coming week is very busy for me. Can you remind me after this coming week to do this?
Very interesting. I wonder how the implied climate sensitivity varies with assumptions regarding the forcing. For example, Shaviv and Ziskin http://phys.huji.ac.il/~shaviv/tmp/ZiskinShaviv_2column.pdf fit land and SST data to a simple climate model, starting with Hansen’s forcings, but allowing certain forcings (solar variability, aerosols, PDO) to vary so as to give the best fit to the published historical data. If one took their derived forcings, would the result then be consistent with their land/shallow ocean model?
Dr Spencer,
Thank you for this. What do the blue and gray parts of the IPCC Figure 9.15 refer to? Including these also compressed the x-scale and made the correspondence between data and model look better.
Another question — have you looked at Professor Nir Shavig’s analysis of the oceans as a calorimeter? Could this approach provide another independent check on your calculations here?
Sorry I had a spelling error above. I meant Shaviv.
Dr Spencer
A tour de force.
As usual.
A small quibble – I thought Hansen wanted, in his latest (co-authored, not yet peer-reviewed) to relate (increasingly negative, as he saw it) volcanic forcings to the (‘travesty of’©) missing heat content of the oceans (while, no doubt, keeping the sensitivity to CO2 forcings constant).
Yes, in Hansen’s worldview he thinks he KNOWS with certainty what the climate sensitivity is, and that it is pretty high. In that case, for a given amount of warming, you can figure out the net forcing.
The trouble is that there has not been as much warming as expected for high climate sensitivity and the forcing from increasing CO2, so Hansen has to find some COOLING influence that he presumes in canceling out much of the CO2 warming.
His latest thing is claiming we are experiencing a delayed rebound effect from Pinatubo cooling. I find this very unconvincing.
These folks will go through all kinds of contortions to preserve their belief in high climate sensitivity, because without that, there is no global warming problem.
Noblesse Oblige-that link is broken. A shame, as I was looking forward to it…
Roy, on the matter of this analysis, I suspect that the answer you will get is that this fit could be achieved with higher sensitivity if we just insist that aerosol cooling must be larger! The modelers have long since passed the point of making falsifiable claims and now instead have endlessly adjustable models that can be “fit” to any data. Also they will probably claim that the Ocean Heat Content data is very uncertain (and so it is, prior to ARGO, but warming is “mysteriously” missing from that!) so the models and data are still “consistent”.
BTW any idea why the warming at depth of 150 meters so different from that above and below it?
Andrew, yes, you are correct. Higher sensitivity can be preserved by simply assuming there are stronger cooling influences canceling out the CO2 warming.
That cool notch at 150 meters, if real, suggests either (1) some relatively recent cooling event mixing down from above, or (2) some enhanced deep-ocean mixing which brought unusually cool water upward.
It is an interesting feature, I expect we will see research published on it at some point.
Very good. I like to see the IPCC put in its place, and be called it on its cheating. The good Dr Spencer is doing it for us, and we are mighty glad to see him do it.
But as an inveterate fault-finder I still have a complaint about Dr Spencer’s logic, in which he has not yet fully repudiated the IPCC errors. Eventually we need a case as strong and nearly flawless as we can get, not contaminated by IPCC errors.
Dr Spencer writes: “in the global average, long-term temperature change is only a function of 3 basic processes:
1) the strength of the forcing (imposed energy imbalance on the climate system, due to whatever);”
They mix up internal state variables with external driver variables, and thereby degrade their ability to sort out cause and effect. In this instance, the evil IPCC word “forcing” is the problem. A forcing is a variable that comes into the calculation of the progress of events in the system, but it is not necessarily a simple and immediately directly physical variable. It can be, for example, a radiative imbalance at the top of the atmosphere. This is determined by both internal state variables such as cloud cover and atmospheric composition, as well as by external drivers such as the distance of the earth from the sun, and the various emanations of waves and fields and particles from the sun, and the motion of the moon. Thus it is not really a “basic process” as asserted by the good Dr Spencer. No single basic physical variable can “impose” an energy imbalance at the top of the atmosphere; the imbalance is physically compound. Mathematically, a “forcing” is a recognized element of a calculation, but physically it is an unidentified compound of many unidentified (“whatever”) physical elements. Physics is about physical elements and they are about immediate direct singular causality. Dr Spencer uses the phrase “due to whatever” I think with the intention of heading off whinges like mine here. But we whingers are not easily put off, and that one didn’t work for me.
Consequent on the conceptual muddle of the term “forcing” is logically necessary a conceptual muddle about what is a “feedback”. These two terms are twins born of the IPCC “forcings and feedbacks” formalism. They are arbitrary calculational artefacts, not rooted in singular causality as required for physics. Dr Spencer writes: “Everything else is details.” No, I say, physics is not to be dismissed as mere “details”. The Bode 1945 feedback concept requires the circuit designer to arbitrarily designate what he wants to consider to the signal path and the feedback path; these concepts are purposefully chosen by the engineer, and do not spring spontaneously from the raw physics. Engineering is about artifice. Physics is about nature. The thinking is different. The Bode 1945 concept is good for its engineering purpose but the IPCC “forcings and feedbacks” formalism is about a different problem and is not good for that problem. We want a conceptually clean theory instead. Christopher Game
Christopher,
You really should get together with physicist G White. He seems to argue many of the same things – that the way the IPCC’s ‘forcings and feedbacks’ models the climate system into a feedback loop is incorrect because it doesn’t account for the physical feedback system controlling the Earth’s energy balance, but rather to some ‘hypothetical feedback system controlling the surface temperature’.
You may find his comments here of interest:
http:// scienceblogs.com/deltoid/2010/07/open_thread_51.php#comment-2655586
http:// scienceblogs.com/deltoid/2010/07/open_thread_51.php#comment-2659228
http:// http://www.palisad.com/co2/fbe/fb.png
Christopher, you are getting into the “details” I mentioned.
Maybe what you are getting at is the virtual futility of separating “forcing” from “feedback” in the climate system, since these are human conceptual simplifications of what are in reality very complex interactions (?)
I’ve brought this up before, but if the IPCC is claiming a 40 year delay between forcing and final response due to the thermal inertia of the oceans, how do they even explain seasonal hemispheric change in average SST of about 5 C that occurs in just 6 months time? With a 40 year delay there wouldn’t be any seasonal change at all. There would barely even be any difference between night and day with that long of response time.
Even globally, the temperature changes by 3-4 C in just 6 months time. Clearly a very shallow depth of ocean water is involved in these changes or they simply would not occur. It seems to me that unless the IPCC wants to argue that GHG ‘forcing’ heats the ocean from the bottom up and solar ‘forcing’ heats it from the top down, they really don’t have a case here.
Or I’m I missing something?
The seasonal change is a HUGE forcing, and because of it’s relatively short time scale (months), its effect is felt mostly in the mixed layer. Now, it probably DOES propagate downward, but it gets damped as it does, just like seasonal variations in soil temperature do when you go down a few meters.
But if there is a PROLONGED forcing, many decades, then it takes along time for the “whole” ocean to respond. Remember, the seasonal cycle, by definition, involves no long-term change.
Dr. Roy, you say:
“The seasonal change is a HUGE forcing, and because of it’s relatively short time scale (months), its effect is felt mostly in the mixed layer. Now, it probably DOES propagate downward, but it gets damped as it does, just like seasonal variations in soil temperature do when you go down a few meters.
But if there is a PROLONGED forcing, many decades, then it takes along time for the “whole” ocean to respond. Remember, the seasonal cycle, by definition, involves no long-term change.”
I know the seasonal cycle does not involve long-term change and averages out to zero over the year. The point is as the forcing changes, the response of the SST is rapid and significant. Far too rapid for a decades long response time. A few years probably – not decades (and certainly not 40 years!). The extra few milliwatts of ‘forcing’ from CO2 each year are just rolled on top of the seasonal changes in solar flux.
This is what I don’t understand. Under what physical law would the oceans respond slower to smaller forcings than the would to larger forcings?
It seems to me that because the CO2 is gradually added to the atmosphere over decades, the response time is a non-issue unless one wants to argue the last 4 or 5 parts per million have not yet reached equilibrium, which is an infinitesimal imbalance.
Furthermore,
As we all know, the second law says heat only travels from warm to cold and not the other way around. All that matters is how quickly the SST responds to changes in forcing, as any SST change that occurs from a forcing cannot warm the SST any further in the future. I do not see how the entire ocean or even the deeper waters could heat the surface any further over time.
RW,
You stated:
“This is what I don’t understand. Under what physical law would the oceans respond slower to smaller forcings than the would to larger forcings?”
Could you be confusing time constants with derivatives?
Since heat flow (and mixing???) is proportional to the temperature difference, one would expect that the response would take the form of a decaying exponential, exp(-t/Tau), where Tau is the time constant. Or perhaps a sum of such exponentials. The derivative of a decaying exponential will indeed be large for a large ‘forcing’ and small for a small forcing, for a ‘constant’ time constant.
Apologies if I’m missing something obvious here. This stuff is way out of my field!
To be more positive:
In global average, the long-term temperature change is determined by the internal dynamical structure of the system and by the external drivers. The internal dynamical structure is in principle itself variable, but for the present we suppose it is in a dynamically stable régime that we can analyze.
Heat is absorbed more at the tropics and is partly transported towards the poles for emission to space. The tropics have a stabilizing factor, as it were a ‘non-equilibrium quasi-boiling-point’, a slightly flexible temperature reference system, manifest in the protected towers of deep tropical convection of Riehl and Malkus 1958, also known as the penetrative convection of Lindzen 1977. You can see them as you fly over the Pacific Ocean near the equator.
The IPCC has us like a boat dragging a sea-anchor with no fixed reference at all, just simply driven by the imbalance at the top of the atmosphere. Their sea-anchor is even troubled by a tendency to get out of line so as to be inefficient. This is their beloved “positive feedback” story.
We are not anchored by an immovable anchor, locked in the rocks at the bottom, with an iron chain.
But we do have a relatively immovable anchor, stable in the present dynamical régime, and an elastic cable, that give the climate some element of stability as well as some elasticity. The anchor is the protected towers, the elastic cable is the extent of the para-tropical warm region which they generate. As this region widens, the global average temperature increases. This is a negative feedback scenario, and seems likely on the basis of cloud feedback according to Dr Spencer. One might call it a ‘phase-pinned’ dynamical structure. Christopher Game
Replying to RW’s post of June 25, 2011 at 4:31PM, about George White. Though George’s work has some merits, I find George’s thinking seems tied too much to engineering and not enough to physics. Christopher Game
While I agree he generally seems to take more of a ‘system’s engineering’ approach to the climate, I like his approach to the subject. He does a lot of thinking outside the box and always seems to try to corroborate the data with raw physics and the system behavior as a whole. So I guess we disagree there. I also like that he is self-funded and does all his own work.
If you notice, the results of his research are very consistent with that of Dr. Roy and Richard Lindzen, which I think only further confirms they’re getting it right and the IPCC is getting it wrong.
Equilibrium Climate Sensitivity doesn’t depend on ocean diffusivity.
Oliv, while it is true that EQUILIBRIUM climate sensitivity does not depend on ocean diffusivity. But the system is never in equilibrium, and so a 40 year temperature trend (the “transient” response) DOES depend on ocean diffusivity.
You say : “This is well below the range of warming the IPCC claims is most likely (2.5 to 4 deg. C).”
“2.5 to 4 deg. C” is an ECS range.
RW,
“I do not see how the entire ocean or even the deeper waters could heat the surface any further over time.”
The surface of the ocean could warm more when the cold deep ocean warms. This happens by not conducting as much heat to the depths because of the lower deltaT. This is not a violation of the second law.
The post shows that ocean depths are not warming according to the models. If they don’t warm, the sst should have been warmer than we measure and the forcing must have been lower than stated by the IPCC. The trapped energy went somewhere – or it didn’t exist. This simple model shows that it is possible that less mixing and less forcing are able to match the observed data more closely than main stream assumptions.
The “missing energy” has just radiated away into space over the years because the water vapour feedback is much weaker than the IPCC thinks. Alternatively, cloud cover has increased in a slightly warmer, wetter atmosphere – so that more incoming solar is bounced back into space.
Those are the two most economical reasons for the “missing energy”
Jeff, I think the forcing in the model is the same as that used by GISS. It’s the sensitivity that’s less. Which does imply that the radiative forcing was partially canceled by negative feedback, or less positive feedback than the models generally have anyway. Basically less amplification of the heat going into the system from positive feedback, so less ocean warming. Less forcing could also be used if one insists the sensitivity of models is correct.
What I find most important about this is that it shows, contrary to some claims, the ocean warming is not inconsistent with a low sensitivity, even allowing for the reduced forcing from aerosols…so that unless the aerosol forcing is even more strongly negative than GISS thinks, the data are not merely compatible with a low sensitivity, they seem to imply it. Of course, aerosols are the favorite fudge factor of modelers because they are very uncertain, so they can plausibly say that this result doesn’t prove low sensitivity. But it cannot be ruled out.
oliv, what is the basis for your claim, and what is your point?
Andrew,
My point is that Roy Spencer use the term “sensitivity” that have different meanings.
He speak about TCR (Transient Climate Response) and compare his TCR estimation to Equilibrium Climate Sensitivity (ECS) estimations.
The TCR is lower than the ECS.
http://en.wikipedia.org/wiki/Climate_sensitivity
Thanks very much for your good work, Dr. Spencer. It’s my birthday today and this was a great present!
Jeff Id says:
“The surface of the ocean could warm more when the cold deep ocean warms. This happens by not conducting as much heat to the depths because of the lower deltaT. This is not a violation of the second law.”
I guess what I was saying is that once the change in ‘forcing’ has heated as much water as it’s physically capable of, the deeper ocean water can’t warm the surface water any further.
The amount of SST increase we see hemispherically at the peak of every summer supports that only a very shallow depth of water is involved in the heating of the ocean from increases in radiative forcing. A precise calculation would be hard to figure out, but +5 C SST in each hemisphere in just 6 months time is an absolutely enormous amount of change really fast, even considering the huge change in energy flux. If the entire ocean or significantly deeper depths are required to warm in order to fully effect increases in forcings, this much seasonal SST change would simply not occur, and there would be little (if any) seasonal change at all.
Also, as huge as the hemispheric seasonal change in energy flux is, it’s still absolutely tiny compared to the total heat capacity of the entire ocean.
RW-“as huge as the hemispheric seasonal change in energy flux is, it’s still absolutely tiny compared to the total heat capacity of the entire ocean.”
But not as tiny when compared to the heat capacity of the entire atmosphere. And it is primarily heating/cooling of the atmosphere, not the ocean, that seasonal insolation cycles achieve. Just witness the distinctly smaller amplitude of the annual cycle in ocean temperatures versus atmospheric temps
The atmosphere can probably be thought of as having an “initial” response time for the system, the ocean contributing the full response time. For the atmosphere that is very short, maybe a couple months at most. For the ocean it’s probably anywhere from about year to much longer.
Lindzen and Giannitsis found that just how long the response time is depends on the sensitivity:
http://eaps.mit.edu/faculty/lindzen/184_Volcano.pdf
So a lower sensitivity would tend to be associated with a shorter response time. However, again there is a quick response for the atmosphere alone which gives rise basically to the seasonal cycle even though the full response time of the coupled system is longer.
Andrew,
I’m not quite sure what you’re saying here. Yes, the heat capacity of the atmosphere is small – something on the order of about 1-2% of the entire thermal mass of the planet (I think about 5% is in the land mass and over 90% is in the ocean). The atmosphere doesn’t have enough thermal energy to heat the surface to any significant degree – it primarily just slows cooling of the surface (via GHGs and clouds).
The atmosphere is more or less acting a ‘filter’ between the surface and space. The average near ground air temperature is determined by the actual surface temperature of the ocean and land masses. Obviously the land masses respond much quicker than the oceans to changes in forcing due to their smaller heat capacity. In effect, the large heat capacity of ocean continues to cool much longer until equilibrium is reached – lengthening the response time significantly.
RW-Yes, sorry, I was referring to both the atmosphere and landmass, as both have a shorter response time than the system as a whole.
Although there is much to like in this analysis, I can’t agree with “the total heat carrying capacity of the ocean varies linearly with depth”. The problem is that you’re modeling a global average, and ocean area isn’t constant with depth.
yes, of course, the bottom of the ocean is not flat…I meant the “depth of the water”. That should have been obvious from the context.
I think this is a useful description of the significance of oceanic behaviour:
http://www.irishweatheronline.com/features-2/wilde-weather/setting-and-maintaining-of-earth%e2%80%99s-equilibrium-temperature/18931.html
Christopher Game replying to Dr Spencer’s post of June 25, 2011 at 5:31PM.
Dr Spencer rightly points to the timing of the seasons. As a good approximation, the seasonal driver is nearly sinusoidal, and this reveals responsiveness at just one frequency, which makes only a small contribution to the non-periodic long-term changes of interest in climate science.
Nevertheless, as Dr Spencer notes, “The seasonal change is a HUGE forcing”. So it ought to be the easiest frequency component to measure. Indeed one would expect to be able to measure it with very good accuracy and precision. Very good accuracy and very good precision. Though small, this precisely measurable contribution is non-zero and plays a part. Dr Spencer is not quite to the point when he uses the words “involves no long-term change”; the pulse and step and other transient responses involve all frequencies.
But instead of taking advantage of this accurate and precise information offered by nature, climate scientists often ‘let nature do the averaging’ and they “average out” the seasonal signal as if it were only a nuisance variable, and ignore the relevant information it could give them. This is wrong on three counts:
(1) it is methodologically wrong in statistical estimation to “average out” nuisance variables; instead one should estimate them and remove the estimates explicitly.
(2) though it is indeed at only one frequency, that is (like one’s wife) the only one that one has, and a precious treasure, because of its accuracy and precision. (There are other frequencies available, not with such a HUGE amplitude, but still worth investigating.)
(3) this “forcing” is not a “forcing” in the most commonly used IPCC sense because it is not an imbalance at the top of the atmosphere. The related contribution to the usual IPCC “forcing” involves not only the astronomical variables, which are external and not subject to feedback, but also the cloudy albedo effect, an internal state variable subject to so-far hardly estimated feedback. As the good Dr Spencer has admirably shown, this makes it very hard to distinguish cause and effect when using such “forcing”.
But the seasonal effect is responding to a pure and true and fairly precisely measurable external driver that suffers no feedback; for the terrestrial seasons do not affect the astronomical factors. It provides a clean separation between cause and effect. Yes, different for the two hemispheres, and at only one frequency; but still a clean separation. True, there is the complication of interhemispheric exchange according to Dr Lindzen’s view that the Hadley cells span the two hemispheres much of the time. (end of numbered points)
Here we have a clean and accurate source of relevant information, and all that most climate science does with it is to discard it by ‘letting nature average it out’, without even bothering to estimate it explicitly. No wonder we have difficulties here.
True, in this approach, data at more, and at more relevant, frequencies are needed. True, the seasonal response is non-linear, so that harmonic distortion creates problems; but some aspects of it are nearly linear.
People have tried to use the pulse response to volcanic eruptions, and this can provide some limited information, but has its problems.
The Great Pacific Multidecadal Oscillation most likely has a so-far unidentified external driver, but still its effect should be investigated. It is not even known whether the signal is strictly periodic, I think.
The external driver that is correlated with the sunspots is perhaps unidentified, but still its effect should be estimated and investigated. It is not strictly periodic over a single solar cycle but the paired 22-year cycle is more nearly periodic. The departures from strict periodicity are themselves informative. Dr Spencer has made some steps towards investigating this, but could go further with it, or perhaps persuade a colleague to do so, if funding were available.
Dr Spencer uses an autocorrelogram method with his models that he has recently posted here, and in doing so he deals with effects at times as short as a month or so; these short times are not more relevant to “long-term change” than is the seasonal cycle. Dr Spencer should demonstrate that his almost ‘uncalibrated’ autocorrelation results are consistent with the rigorously reliable seasonal results, and even use the seasonal results to ‘calibrate’ the autocorrelation results.
The mathematical and statistical analysis needed for this kind of investigation is a very specialized and imperfect art. The specialist climatologist, even of Drs Spencer and Braswell’s high calibre, cannot also have this specialized art, to know all the ins and outs and imperfections of it. But I can hardly believe that America does not have a good supply of specialist mathematicians who could help Drs Spencer and Braswell (and Dr Lindzen, for that matter) with the problem. Are all those mathematicians afraid of the political clout of the IPCC and their allies in America? One can hardly overestimate the vise-like grip the IPCC people have on funding. Christopher Game
@Stephen Wilde
What portion of solar energy is capable of warming 200m deep layer of the oceans?
And what about that cool thin layer on the ocean surface, given that the ocean is in constant movement, waves and streams are mixing the water constantly.
And on evaporation: I think that the(average) atmospheric pressure differences are abysmall factor compared to direct solar irradiance of oceanic surface, which I think causes most of the evaporation (of course given the saturation of air above it).
Lower atm. pressure usually means more clouds, whereas high pressure means less clouds. This would alltogether lead to a circle (what you are, after all, assuming)disabling any abrupt changes of temperature equilibrium caused by solar activity changes. Aren´t you contradicting yourself?
PS: If my assumptions or knowledge is out of bounds of physics or lacks logic, let me know.
Martin:
i) “What portion of solar energy is capable of warming 200m deep layer of the oceans?”
Any solar energy that gets past the ocean skin. Mostly visible and more energetic short wavelemgths.
ii) “And what about that cool thin layer on the ocean surface, given that the ocean is in constant movement, waves and streams are mixing the water constantly.”
I mention that in some detail so I’m not sure what point you are making. It never goes away for long over any significant areas despite variable amounts of mixing locally.
iii)” And on evaporation: I think that the(average) atmospheric pressure differences are a small factor compared to direct solar irradiance of oceanic surface, which I think causes most of the evaporation”
It is the absolute atmospheric pressure that dictates the energy value of the enthalpy of evaporation. Regional or local atmospheric pressure differences only attend to very fine adjustments in the energy flow from sea to air to space but those adjustements seem to be enough to exert a negative response to any other forcing effect so as to maintain overall system equilibrium.
iv)”Lower atm. pressure usually means more clouds, whereas high pressure means less clouds”
Not quite, more cloud results from mixing at air mass boundaries. Most mixing occurs within low pressure systems which develop along air mass boundaries such as between the subtropical high pressure cells and the polar high pressure cells.If solar changes alter the surface distribution of the polar high pressure cells then the length of the air mass boundaries changes due to the spherical nature of the globe. Longer boundaries give more mixing and more clouds and one gets longer boundaries from either/or more meridional jets/more equatorward jets.
Stephen Wilde.
I think that UV does not penetrate water very good, regarding the usage of UV lamps on purpose of disinfection of water. The water must be filtered through a thin tube, if the lamp is above surface, no disinfection happens.
And visible light: in depth of 50m or somewhat more is permanent darkness, isn´t it?
http://www.slrss.cn/download/05_SCI/Penetration%20of%20solar%20radiation%20in%20the%20upper%20ocean%20A%20numerical%20model%20for%20oceanic%20and%20coastal%20waters.pdf
Nothing gets much past 200 metres.However there is some suggestion that once the water above 200 metres has been warmed the energy can be subducted along the thermohaline circulation.
Infra red generally does not get past the ocean skin so it is lost in faster evaporation from the surface.
In between is the domain of the solar shortwave radiation.
A simpler graphic here:
http://oceansjsu.com/105d/exped_briny/13.html
The slower than expected (based on models) warming below the first 100 meters or so appears related to the lack of fall-off in the rate of CO2 absorption by the ocean. The standard Bern model suggests a significant fall-off over time in the rate of CO2 uptake, while CO2 absorption has remained remarkably constant at ~50% of total emissions. An ocean that is more stably stratified, and where CO2 uptake is mainly driven by thermohaline circulation (CO2 absorbed by sinking cold water) rather than by eddy driven down-mixing into the thermocline, is perfectly consistent with both less than expected warming and more constant than expected CO2 uptake.
Down-mixing of heat and CO2 into the thermocline must happen together. A shortfall in one (heat) automatically indicates a shortfall in the other (CO2).
I am always intrigued by the 50% uptake of co2 emissions by the oceans. I think it’s telling us something important. CO2 is not just dissolved in ocean water as carbonic acid. It can combine with alkaline earth ions to make magnesium bicarbonate or calcium bicarbonate. These are soluble and stable in cold water. If you warm them up however, they become unstable precipitating out magnesium carbonate and calcium carbonate ( sequestering half the CO2) and releasing the other half as carbonic acid and re-emitting the CO2. So is 50% uptake a coincidence or does it reflect the stoichiometry of the sequestering chemistry?
A little while back I did some sine fitting on the ARGO data at 45 S and produced charts of amplitude, mean, phase, and R2 by depth. The annual amplitude signal does indeed diminish very quickly in the upper levels.
http://sites.google.com/site/climateadj/argo-sine-fitting
Based on similar charts I had produced using the model data, I would have thought that the greater the amplitude the less sensitive the model was. I haven’t done a regression to see if this relationship holds up (at least at this particular latitude using this particular method).
I wonder if the “power” of the annual signal can be calculated at a global level and if there is a relationship with model sensitivity? Would Welch’s Method be appropriate for this task?
Well of course the heat exists. All the forensic evidence (melting polar ice, escalation of extreme weather events and such) proves that.
It seems that a warmer ocean surface would make it harder for warm water to push into the deep. Heat moves upwards.
Dragontide,
apparently you don’t pay attention to even the IPCC types telling us that the extreme weather events are NOT due to warming, whether AGW or otherwise.
You also haven’t been paying attention to the MULTIPLE reports from NASA and others that the melting Arctic is mostly due to WEATHER. That is, high pressure areas and winds and sea currents pushing the ice out of the Arctic. The current air temps in the Arctic and last melt seasons were actually slightly LOWER than the norm.
Forensic evidence?? You been watching too much TV dude.
I have a question regarding CH4 (methane) I hope Dr Spencer, or someone else here can answer.
According to the mainstream – IPCC – etc, a doubling of atmospheric co2 will result in an increase of radiative forcing by 3.7 W/m2.
?F = 5.35 x 1n C/Co W/m2 http://en.wikipedia.org/wiki/Radiative_forcing
A very important aspect of this I want to highlight, is, that due to the logarithmic effect, a doubling of atmospheric co2, at what ever concentration, will only ever increase radiative forcing by 3.7 W/m2. So, the resulting increase in radiative forcing due to a doubling from say 200 to 400 ppmv will be equal to a doubling from 2,000 to 4,000 ppmv.
The sensitivity the IPCC applies to this figure is 0.8°C per 1W/m2 so that their best guess of a 3°C rise in temperature for a 2 x co2 scenario is reached.
Eg 3.7 x 0.8 = 2.96
Methane is a much more potent greenhouse gas than co2. In fact far more potent according to Global Warming Potential (GWP), a relative measure of how much heat a greenhouse gas traps in the atmosphere by comparison to the amount of heat trapped by carbon dioxide . For example, the 20 year GWP of methane is 56, which means if the same weights of methane and carbon dioxide were introduced into the atmosphere, that methane will trap 56 times more heat than the carbon dioxide over the next 20 years. http://en.wikipedia.org/wiki/Global_warming_potential
As the atomic mass of a co2 molecule is about 44 & that of a methane molecule is about 18, far more molecules of methane would be needed to match the weights.
This leads me to my question;
I would assume that methane acts the same as co2 in regards to increasing radiative forcing through each doubling of its concentration. And as methane is a more powerful greenhouse gas, this resulting radiative forcing increase must be greater than co2’s 3.7 W/m2 for a doubling.
Atmospheric methane increased from about 700 ppbv in 1750 to about 1,800 ppbv today. That is a rise of 160%, far greater than a doubling.
If my assumptions are correct, what happened to the considerate warming this should have resulted in?
They used a log depth scale because otherwise the surface layer would be bunched up into a couple of pixels. This is because the surface layer is tiny compared to the depth of the Ocean. It is a standard way to plot things, although it is true that such plots can give a dangerous false impression.
That said though, given the way that this lot behave, they can no longer ever be given the benefit of the doubt.
Seems the next step is to space the vertical layers of the diffusion model on a logarithmic scale so as to sacrifice resolution where action is not (i.e. deep) and concentrate it where the action is (i.e. shallow).
–
Stephen Wilde (June 27, 2011 at 6:28 AM) provides a quotable quote:
“iv)”Lower atm. pressure usually means more clouds, whereas high pressure means less clouds”
Not quite, more cloud results from mixing at air mass boundaries. Most mixing occurs within low pressure systems which develop along air mass boundaries such as between the subtropical high pressure cells and the polar high pressure cells.If solar changes alter the surface distribution of the polar high pressure cells then the length of the air mass boundaries changes due to the spherical nature of the globe. Longer boundaries give more mixing and more clouds and one gets longer boundaries from either/or more meridional jets/more equatorward jets.”
Consistent with Leroux (1993), Sidorenkov (2005), and LeMouel, Blanter, Shnirman, & Courtillot (2010).
I was going to ask what role the thermohaline circulation (THC) might play here-OR is this rather insignificant? Deep water formation (cf. Gulf Stream) in North Atlantic certainly varies at decadal timescales like synoptic patterns such as the North Atlantic Oscillation. I am not a weather man, but it is notable in the more recent geological record, variations of atmosphereic CO2 have been explained for example from relative contributions from carbonate rocks at (ocean) depth, itself dependent on strength of THC. Where shut-down of THC is thought to have happened, as during Younger Dryas at terminus of Pleistocene, approx. 13-11 KYBP. Tomasz Goslar (Poznan radiocarbon lab) who reconstructed the callibration curve for Younger Dryas notes much lower input of old carbon (enhancing relative young CO2, adding an extra 1000 y to 14C callibration). This suggests that ocean mechanisms themselves are in part responsible for lag-rises of CO2 in ice-core evidence FOLLOWING atmospheric temp. rises.
I think Dr. Roy is correct in that there has been no evidence substantiating Hansen’s feedback sensitivity claims. Enough time has elapsed that combined a 30 year post 1980 warming cycle along with rising CO2 that should have produced clear evidence.
Hansen has invested so much that he will not moderate his claims. True, I am not a scientist, but his work seems to be increasingly irrelevant and tangent to the fundamental work of trying to understand climate through observation. I see study after study using models to confirm people’s idea of what climate will be like in 90 years but no real rush to compare those models with observation over time. I hear climate scientists on the news telling us that the recent round of tornado activity was unprecedented and due, without doubt, to global warming.
The only reason to stay in such a ridiculous debate is over the political ambitions of those who use such statements to justify increasing control and decreasing liberty. So keep up the debunking, Dr. Roy, but don’t be too surprised to find yourself way out in left field shagging down Hansen’s attempts at a home run.
Is there a bug in the equations for Column D? I see the value 418000 in a couple of spots and 41800 in another.
Dragontide, “escalation of extreme weather events”
Except that there is no such “escalation of extreme weather”! I have examined such claims thoroughly and whether it is drought, floods, hurricanes, tornadoes, extra-tropical cyclones (which even theoretically should decrease in frequency and intensity, “more available energy” not withstanding), heat waves and cold waves, and so on and so forth, the trends toward more extremes simply don’t exist.
Clearly, the IPCC has no idea regarding the physics of thermoclines.
@ Stephen Wilde
Your reply on clouds is very good and enlightning, but I was just pointing out that low pressure cells are more convection-friendly.
Thank you for your answers.
Martin
Dr. Spencer,
You disagree with Pielke that ocean heat content is most important. I think ignoring that fact that 90% of the ocean’s volume lies below the thermocline at a nearly constant temperature near 3C. A thin surface layer of warmer water is the only thing protecting us from what’s essentially a huge bucket of nearly freezing water waiting for an opportunity to suck all the interglacial heat out of the upper layer and plunge us back into a 100,000 year glacial epic.
I think that’s more important than anything. The average surface temperature of the darn planet is about 4C when averaged over one glacial/interglacial period. How do warmists think civilization would deal with that?
P.S. salt water density
Every time I mention the ocean being so darned cold below the thermocline someone claims that’s because 3C is the highest density point of water. That’s only true for fresh water. Sea water keeps increasing in density all the way down to its freezing point near -2C. The deep ocean is 3C because that’s about the average temperature of the surface water over the course of a complete glacial/interglacial cycle. There is no other possibility. The vertical mixing rate might be slow but 100,000 years is enough time for conduction alone to equalize temperature all the way to the bottom.
Thank you Dr Roy Spencer!
You have confirmed everything I’ve been saying for the last two years about the mixing of excess solar energy into the ocean.
My simple model shows how cumulative counting of the sunspot number either side of the ocean equilibrium value demonstrates that the Sun, not co2 warmed the ocean from 1934 to 2003.
Since which time it has been cooling, as the Argo data and my model show.
http://tallbloke.wordpress.com/2010/07/21/nailing-the-solar-activity-global-temperature-divergence-lie/
kuhnkat says:
June 27, 2011 at 9:00 PM
“Dragontide,
apparently you don’t pay attention to even the IPCC types telling us that the extreme weather events are NOT due to warming, whether AGW or otherwise.
You also haven’t been paying attention to the MULTIPLE reports from NASA and others that the melting Arctic is mostly due to WEATHER. That is, high pressure areas and winds and sea currents pushing the ice out of the Arctic.”
The IPCC and NASA said no such thing.
Polar ice is also melting in the Antarctic. Not just the Arctic.
kuhnkat says:
“The current air temps in the Arctic and last melt seasons were actually slightly LOWER than the norm.”
The melting seasons have been starting up to 50 days earlier according to the NSIDC.
Andrew says:
June 28, 2011 at 9:38 AM
Dragontide, “escalation of extreme weather events”
Except that there is no such “escalation of extreme weather”! I have examined such claims thoroughly and whether it is drought, floods, hurricanes, tornadoes, extra-tropical cyclones (which even theoretically should decrease in frequency and intensity, “more available energy” not withstanding), heat waves and cold waves, and so on and so forth, the trends toward more extremes simply don’t exist.
You should pay more attention to the NWS, NOAA and the WMO.
IMPORTANT NOTE: The above model simulation does not account for the possibility that some of recent warming could have been due to one or more natural processes, in which case the diagnosed climate sensitivity would be even lower.
Dr. Spencer
I wonder if you are aware of this work by Emile-Geay and Madec from 2009 that suggests that the contribution of geothermal heating to oceanic temps has been seriously underestimated.
http://www.ocean-sci.net/5/203/2009/os-5-203-2009.pdf
If you have seen it I would be interested in your impressions of it. It is somewhat beyond my technical knowledge to detect if they have gotten anything seriously wrong, but on the surface it would seem that, if they are correct, the work deserves more attention than it seems to have garnered.
Dragontide-“You should pay more attention to the NWS, NOAA and the WMO.”
http://en.wikipedia.org/wiki/Argument_from_authority
Can you cite actually evidence and data that weather is getting more extreme, rather than just telling me I need to listen to authoritative groups? But for the record, NOAA shows this for tornadoes:
http://www.ncdc.noaa.gov/img/climate/research/tornado/tornadotrend.jpg
for drought and wetness:
http://www.ncdc.noaa.gov/img/climate/research/2010/ann/Reg110_wet-dry_bar01001210.gif
For tropical cyclones of the East North Pacific and North Atlantic:
http://www1.ncdc.noaa.gov/pub/data/cmb/images/hurricane/2009/annual/2009EastPacACE.png
http://www1.ncdc.noaa.gov/pub/data/cmb/images/hurricane/2009/annual/2009NorthAtlanticACE.png
Now these data are mostly for the US, but that’s what I’d have to limit myself to if I were to only be allowed to cite “authorities” like NOAA…in reality the facts don’t stop there. If you happen to be actually interested in data on how extremes are NOT increasing, I’d be happy to discuss them. But merely saying “You should listen to NOAA” is absurd. In fact I am quite familiar with the facts, you clearly aren’t.
Dragontide,
http://earthobservatory.nasa.gov/Features/SeaIce/page3.php
“The Arctic Oscillation’s strongly positive mode through the mid-1990s flushed thicker, older ice out of the Arctic, replacing multiyear ice with first-year ice that is more prone to melting.”
http://www.nasa.gov/vision/earth/lookingatearth/quikscat-20071001.html
Nghiem said the rapid decline in winter perennial ice the past two years was caused by unusual winds. “Unusual atmospheric conditions set up wind patterns that compressed the sea ice, loaded it into the Transpolar Drift Stream and then sped its flow out of the Arctic,” he said. When that sea ice reached lower latitudes, it rapidly melted in the warmer waters.
“The winds causing this trend in ice reduction were set up by an unusual pattern of atmospheric pressure that began at the beginning of this century,” Nghiem said.”
Sorry bud, like I said, you and many others just aren’t paying attention. This year we have a combination of warmer ocean currents from the El Nino, current strength, and wind strength and direction causing the large melt. Should be interesting to see if we get a recovery similar to 2008 if the extent drops to the 2007 area.
As far as the Antarctica, the ice is still about normal. Where’s the melt??
But hey, thanks for waving your arms and cooling me off. It is a toasty 80F here in Southern California although it has been running as much as 10F below normal a lot this winter and spring with extra rain and snow. Hope you can make it up to enjoy the July 4th snow skiing at several areas!!
Dragontide,
forgot your NSIDC up to 50 days earlier for beginning melt:
http://ocean.dmi.dk/arctic/meant80n.uk.php
Nope, don’t see it. Must be something they are drinking. Look on the left for the historic charts.
Roy, I’ve got a comment stuck in moderation. Could you perhaps expedite it’s approval? I used a lot of links so I am not surprised that it would be mistaken for spam.
Why dont you get this paper worked up into something that would get into those “peer reviewed journals”. I cant see how it could be rejected – as thousands of papers trying to reconcile observation to models are accepted?
if it isnt peer reviewed it is easily dismissed, (as I am sure you are aware)
So .. umm.. ..the transient climate sensitivity you find, Dr. Spencer, is lower than the IPCC’s equilibrium climate sensitivity. And so… ??
Care to elaborate on why this shows anything wrong with the mainstream view?
Senator Malarkey-When did Roy ever say that he found a transient sensitivity lower than the equilibrium sensitivities? The 1.3 for a doubling of CO2 in his model is the equilibrium sensitivity. I don’t get why people don’t understand this point.
Dave Sprigner says: (June 28, 2011 at 10:49 AM)
“The deep ocean is 3C because that’s about the average temperature of the surface water over the course of a complete glacial/interglacial cycle. There is no other possibility.”
My understanding was that the 3C is derived from polar waters which sink and flow around the deep ocean basins, so there clearly is another possibility, whichever reason is correct.
From the most recent peer-reviewed paper on the issue (Kouketsu et al. 2011):
“We calculated basin-scale and global ocean decadal temperature change rates from the 1990s to the 2000s for waters below 3000 m. Large temperature increases were detected around Antarctica, and a relatively large temperature increase was detected along the northward path of Circumpolar Deep Water in the Pacific. The global heat content (HC) change estimated from the temperature change rates below 3000 m was 0.8 × 1022 J decade?1; a value that cannot be neglected for precise estimation of the global heat balance. We reproduced the observed temperature changes in the deep ocean using a data assimilation system and examined virtual observations in the reproduced data field to evaluate the uncertainty of the HC changes estimated from the actual temporally and spatially sparse observations. From the analysis of the virtual observations, it is shown that the global HC increase below 3000 m during recent decades can be detected using the available observation system of periodic revisits to the same sampling sections, although the uncertainty is large.”
See also:
http://news.discovery.com/earth/antarctica-melting-warming-penguins-101214.html
http://www.nature.com/nature/journal/v465/n7296/abs/nature09043.html (admittedly, concerning upper ocean)(Lyman et al, 2010)
http://www.reportingclimatescience.com/news-stories/article/cancun-climate-change-conference-climate-science-facts-about-global-warming.html
Rog Tallbloke- you are 100% correct. It is just so amazing how most people keep trying to find internal changes on the earth for the cause of climate change, and for that matter geological activity.
They are 100% wrong, the route cause is all external,and this point will be proven this decade.
When the temperature data comes out for June ,I will release my SOLAR/ALBEDO/CLIMATIC RELATIONSHIP paper on this site.
I am sure many will say,it just is not so. They will say it because they can’t bring themselves to accept that it is external forces that control the climate on earth not internal. These external forces then driving the internal forces on earth to shape the climate.
How arrogant they are to think otherwise, and when Co2 increase caused by man is brought as a cause for climate change, well that is beyond arrogant.
This decade will go a long way in setting the record straight, as it wil become clearer that our way of thinking ,is the correct approach to how to evaluate what makes earth’s climatic system tick. I am more confident then ever that I am on the correct path ,along with others such as yourself and Piers Corbyn ,to name a few.
Excellent post; I entirely agree that AOGCM’s mix heat into the ocean far too rapidly, which is necessary in order for them to match the surface temperature record (assuming their climate sensitivities are excessive).
Interestingly, if one reworks the Gregory 2002 study using GISS estimates for forcings and revised (Levitus 2005) ocean heat content estimates, the resulting estimate of equilibrium climate sensitivity is 1.3 deg.C, in line with your estimate. That study (An Observationally Based Estimate of the Climate Sensitivity: J M Gregory et al; J Clim), which formed part of the IPCC’s AR4 evidence for climate sensitivity, was based only on forcing, ocean heat flux and global mean temperature change.
Many thanks for posting the spreadsheet model. The formulae used in the main table don’t handle diffusion quite in the way I am used to, so I haven’t yet worked out the usual (heat) diffusion coefficient (in m^2 per second) that corresponds to your turbulent heat diffusion coefficients. And I couldn’t see where you had adjusted for the ocean only covering 71% of the earth’s surface?
Nic Lewis:
“Interestingly, if one reworks the Gregory 2002 study using GISS estimates for forcings and revised (Levitus 2005) ocean heat content estimates, the resulting estimate of equilibrium climate sensitivity is 1.3 deg.C, in line with your estimate.”
Hi Nic, do you have a link or script for this? I’d be interested in taking a look. I recently posted on reworking through Forster and Gregory 2006 (The Climate Sensitivity and Its Components Diagnosed from Earth Radiation Budget Data), and while I’m able to get similar results for their 11 years of annually averaged data, using the 72-day averages during Pinatubo years I end up with a sensitivity of barely over 1 degree C, similar to what Dr. Spencer got in his analysis with MSU data during the Pinatubo years (although there’s a lot of noise present).
Dr Spencer,
I am a big fan of yours, and so I say for your scientific soul that you must, MUST unglue yourself from the application of linear feedback models. If the rest of this posting sounds aggressive, I assure you that I proffer it mainly in the hope that it helps to deepen your self-questioning.
You have demonstrated here a discrepancy in the cumulative net energy gain modeled by PCM1 against observation. I am sure that the discrepancy is real, and that it is due to an incorrect modeling of forcing and feedbacks by PCM1. I am also certain that a number of other GCMs show a similar vector of error in energy gain in the form of OHC.
You then go on, however, to conclude on the basis of a linear feedback model, that
QUOTE The results here suggests the warming has been considerably weaker than what would be expected for a sensitive climate system.
The sensitivity number I estimate — 1.3 deg. C — arguably puts future warming in the realm of “eh, who cares?” ENDQUOTE
I cannot disprove your conclusion about climate sensitivity, but I can say that it is scientifically ill-founded. Equally, if you had argued that the climate sensitivity was 1.8 or 3.0 degrees for a doubling of CO2, I could not disprove it, but I would argue that these values were equally ill-founded, if based on the same data.
You justify your conclusion by stating:-
QUOTE Even though the model I use is admittedly simple, this does not really matter because, in the global average, long-term temperature change is only a function of 3 basic processes:
(1) the strength of the forcing (imposed energy imbalance on the climate system, due to whatever);
(2) the strength of the climate system’s resistance to that forcing (net feedback, which determines climate sensitivity); and,
(3) the rate of ocean mixing (which affects surface temperature, which affects the rate of energy loss to space through feedback processes).
Everything else is details. ENDQUOTE
Your suite of assertions – unintendedly, I am sure – represents a distortion of the mathematical reality. These assertions are ONLY valid once you have already decided that a linear feedback model is valid. You are grossly underestimating what the IPCC euphemistically calls “structural uncertainty”, and what may be more loosely called non-linearities in the feedback equation.
I took some time out recently to post a two-part series of articles on Lucia’s site:-
http://rankexploits.com/musings/2011/equilibrium-climate-sensitivity-and-mathturbation-part-1/
and
http://rankexploits.com/musings/2011/equilibrium-climate-sensitivity-and-mathturbation-part-2/
Ironically, I wrote these articles to show that basing climate sensitivity estimates on the CMIP model suite was fundamentally flawed. These articles, turgid and badly-written though they might be, demonstrate that one can match surface temperature and OHC data, for the same set of forcings, with a wide range of equilibrium climate sensitivities, merely by changing the (assumed) order of temperature-dependent feedback in the radiative imbalance side of the energy imbalance equation.
I would strongly urge you to consider the implications of these articles on your conclusions.
If, after consideration, you believe they are irrelevant, then my offer to you is this:- give me your best estimate of mean surface temperature, (compatible) ocean model and forcing data and I will give you a range of climate sensitivities which fit as well as your best estimates.
Like Feynman, I attack my friends at least as much as my enemies.
Milton H. says:
“Could you be confusing time constants with derivatives?
Since heat flow (and mixing???) is proportional to the temperature difference, one would expect that the response would take the form of a decaying exponential, exp(-t/Tau), where Tau is the time constant.”
No, I’m referring to time constants. I haven’t done any calculations, but the fact that globally averaged temperature changes by 3-4 C in just 6 months time strongly suggests a time constant of only a few years with most of the response coming in the first year. If this was not the case, how could this much change in such a short period of time even occur?
AJ says: (June 28, 2011 at 9:13 AM)
“Is there a bug in the equations for Column D? I see the value 418000 in a couple of spots and 41800 in another.”
Yes, I believe you are correct. The number should be 4180000, that’s right, with 4 zeroes. It is supposed to represent the heat capacity of a column of water of 1 square meter and one meter deep, i.e. one cubic meter. My physics book quotes the heat capacity of water as 4.18 Joule/ºC/gram. Do the sums and you will get 4180000 Joule/m³/ºC. All the columns (D to AG) carry that error.
If we have a bathtub full of water with a large chunk of ice in it, as energy (a sunlamp perhaps) is put into the system the water is likely to cool – at least until the ice all melts.
If, in addition, we have several more chunks of ice sitting on the edge of the bathtub (not in the water), they too will melt and add freezing water to the bathtub; again retarding it’s warming.
Until the ice is all — or nearly all — melted, we can’t expect the bathtub water to increase in temperature in direct correlation to the amount of energy being added.
It takes far more energy to melt ice than to warm an equal amount of water. My guess is that the large volume losses in Arctic sea ice over the past 10 years is largely responsible for the ‘missing’ heat. Especially since the current accelerated rates of arctic ice melt were unforeseen.
According to PIOMAS, the Arctic lost about 8000 km^3 of ice from 2000 to 2010. That’s about 8*10^15 kg of ice. This amount would require ~2.7*10^18 kJ of energy to melt.
The surface area of the oceans is ~3.6*10^8 km^2. This article discusses depths to 700 m, so taking the entire ocean at that depth (yes I know, a poor estimate because a decent amount of the ocean doesn’t reach that depth…but I just want a ballpark estimate) yields a mass of ~2.5*10^20 kg of water.
Using a heat capacity of 4.186 kJ/kg*K, I get the temperature change of this amount of water if no sea ice loss had occurred as 0.0025 K. I know it’s just a ballpark estimate, but that’s a pretty small amount.
Please let me know if there are significant errors in the above estimate…
-Scott
Hello Roy,
Way off left field, but the satellites you get there data from, might they also measure spectral data ? And if these do, what physical surface is so measured?
TALLBLOKE -has it correct, all the warming of last century can be shown to correspond to the short intense solar cycles. The data shows good correlation, as he has shown.
Th missing heat isn’t missing because it is not there to begin with.
As I know and others that have my stance, the other side will try to promate the hoax until the temperatures really show a more dfefinitive decline, which is coming very very soon. They will probably still hang on to their idea.
How this hoax ever took in so many, is beyond me. The absurdity of a trace gas ,somehow controlling earth’s climatic system is a joke.
This will be put to rest soon, and I will be expanding my part to see that it is.
In the meantime the fools keep touting global warming ,when the reality is we our about to go into substancial global cooling.
Man always has to learn the hard way, and this lessen in climate is going to be very hard.
Dr. Spencer, a YouTube video is being widely advertised in association to the Google-searchable exact phrase “Dr. Roy Spencer teamed up with Declaration Entertainment’s Bill Whittle” in producing it.
Why The Left’s Global Warming Agenda Is Flat Out Wrong
URL: http://www.youtube.com/watch?v=vvObfrs3qoE
It’s a very nicely produced video … but the video itself lists no author, narrative, producer, or copyright holder.
Are you in fact the author and/or narrator (etc.) of this video? If not, is it known to you who is?
Dr. Spencer, I have a comment with two NASA links hanging in moderation since June 28th. Could you take a look please?
Now I always said there is no such thing as a silly question but there are lots of silly answers. So I’m going to risk being the exception that proves the rule when I ask:
Is this idea that there’s an ‘energy imbalance’ essentially the work of one man/team or is it yet another ‘scientific’ fact achieved by consensus rather than actual hard scientific method?
I ask because I’m relatively certain that nobody has actually measured the exact amount of energy coming in, the exact amount of energy used to power various physical processes on Earth (from evaporation to winds to whatever), the exact amount of energy taken by various chemical processes such as photosynthesis… my point being I’m fine with trying to estimate these things but the simple fact is that before you go claiming there’s some magical energy imbalance you need to prove, I would hope, that your estimates have really fully taken these things into account.
Basically I haven’t seen a shred of evidence that is the case. I am as convinced that the climate change alarmists have done just as shoddy work this time on this aspect of their false claims as they have with every single other thing they’ve been involved with as their goal is not science but ideology and politics – imposing their worldview on us by perverting science in a way that it becomes a tool with which to frighten us into going along with them no matter what the cost or consequences.
In short, I expect if the hard work is done we will find there is in fact no “energy imbalance” and, to whatever level of accuracy it is possible to attain, in fact all the incoming energy can be accounted for if we just fail to leap to the false conclusion that it cannot AND ACTUALLY TRY TO DO IT.
I spent some time and fixed the 10X error as well as a 100X error noted by Paul K on the Air Vent thread.
In the end the result wasn’t much different excepting the 10x increase in diffusion coefficients.
http://noconsensus.wordpress.com/2011/07/02/updated-spencer-ocean-model/
Dr. Spencer
Thank you for brining some sanity to the discussion. The latest claim by so-called “climatologist” is that the “rapid, anthropogenic” global warming is choking the natural channels of the multi-decadenal cycle, thereby leading to the possibility of rapid global cooling, in turn resulting in a cold snap on par with the last “little ice age” that ended in the early part of the 19th century. This is unparalleled hysteria, but it is also transparent. When the data does not support your hypothesis, you bend the data. When data distortion is no longer enough, you posit new theories to accommodate the paradigm. I really wish you would publish a simple, plain English rebuttal that I can share with my friends who have been duped by this lie. Better yet, I would like to see a highly organized panel of independent, thoughtful, objective scientist like yourself publish an in-depth peer reviewed study that rebuts the IPCC report point for point. This could include IPCC defectors. I of course understand the key is media attention, but if you were to use social media, anything is possible. Meanwhile, thank you again for your dedication to REAL science, one based on data and skepticism, not on hysteria and and political agendas.
Gary Loss
do two times one liters of sea water, with the same salinity and temperature, have the same heat content if one is, say, a 1,000 meters deeper than the other?
If you removed a liter of water, in a insulated pressure bottle, from the bottom of ocean and then measured the temperature prior to and after releasing the pressure, would there be a temperature difference?
Christopher Game responding to the post of Paul_K of June 29, 2011 at 5:08 PM. (Sorry the reply thing doesn’t work for me.)
A linear system has no preferred amplitude of oscillation and no preferred quantities such as a fixed point or stationary state. A non-linear system can have both.
The IPCC “forcings and feedbacks” formalism is linear and has no preferred fixed point.
The protected hot towers of deep tropical convection (Riehl and Malkus 1958, Lindzen 1977) are local manifestations of non-linear dynamics with a threshold. They are like a dynamical non-equilbrium phase change. They tend to keep the temperature of the surface of the tropical ocean near 28C. This is a preferred fixed point. Atmospheric global warming would not alter the tropical ocean surface temperature but instead it would widen the north-south meridional extent of the tropical and paratropical warm zone.
This week I went to the IUGG meeting in Melbourne where I heard Dr Trenberth tell us that he thinks that the hydrological database products are unreliable at their present stage of development. Christopher Game
Dr. Spencer:
Small world: I received my bachelor’s in Chemical Engineering from UAH in 1999.
How significant is the < 0.1 C difference in deep ocean temperatures between the model and observations? My question is in terms of the precision and accuracy of temperature measurements. How can one be sure that the observational dataset does not have a bias (either way)?
Regards,
Albert Zwiener
“the climate system is simply not as sensitive to our greenhouse gas emissions as they claim it is”.
The claim is based on a large body of evidence, including studies of paleoclimate, volcanoes, solar cycle, ocean temperature differences, past projections, and probability studies, as well as complex climate models themselves. There is a remarkable convergence from all these disparate studies for a climate sensitivity of 3*C ~.
The hypothesis that climate sensitivity is low is refuted by this mountain of evidence unless you can comprehensively overthrow each and every one of the papers that contribute to the 3*C figure.
You are studying a complex system, and a simple box model is not fit for purpose in studying such a system, let alone to overthrow such a body of work.
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If any of you are interested, I just posted a critique of Roy’s latest modeling efforts, such as the one in this post.
http://bbickmore.wordpress.com/2011/07/26/just-put-the-model-down-roy/