Guest Post by Willis Eschenbach
Figure 1. The Experimental Setup
I keep reading statements in various places about how it is indisputable “simple physics” that if we increase the amount of atmospheric CO2, it will inevitably warm the planet. Here’s a typical example:
In the hyperbolic language that has infested the debate, researchers have been accused of everything from ditching the scientific method to participating in a vast conspiracy. But the basic concepts of the greenhouse effect is a matter of simple physics and chemistry, and have been part of the scientific dialog for roughly a century.
Here’s another:
The important thing is that we know how greenhouse gases affect climate. It has even been predicted hundred years ago by Arrhenius. It is simple physics.
Unfortunately, while the physics is simple, the climate is far from simple. It is one of the more complex systems that we have ever studied. The climate is a tera-watt scale planetary sized heat engine. It is driven by both terrestrial and extra-terrestrial forcings, a number of which are unknown, and many of which are poorly understood and/or difficult to measure. It is inherently chaotic and turbulent, two conditions for which we have few mathematical tools.
The climate is composed of six major subsystems — atmosphere, ocean, cryosphere, lithosphere, biosphere, and electrosphere. All of these subsystems are imperfectly understood. Each of these subsystems has its own known and unknown internal and external forcings, feedbacks, resonances, and cyclical variations. In addition, each subsystem affects all of the other subsystems through a variety of known and unknown forcings and feedbacks.
Then there is the problem of scale. Climate has crucially important processes at physical scales from the molecular to the planetary and at temporal scales from milliseconds to millennia.
As a result of this almost unimaginable complexity, simple physics is simply inadequate to predict the effect of a change in one of the hundreds and hundreds of things that affect the climate. I will give two examples of why “simple physics” doesn’t work with the climate — a river, and a block of steel. I’ll start with a thought experiment with the block of steel.
Suppose that I want to find out about how temperature affects solids. I take a 75 kg block of steel, and I put the bottom end of it in a bucket of hot water. I duct tape a thermometer to the top end in the best experimental fashion, and I start recording how the temperature changes with time. At first, nothing happens. So I wait. And soon, the temperature of the other end of the block of steel starts rising. Hey, simple physics, right?
To verify my results, I try the experiment with a block of copper. I get the same result, the end of the block that’s not in the hot water soon begins to warm up. I try it with a block of glass, same thing. My tentative conclusion is that simple physics says that if you heat one end of a solid, the other end will eventually heat up as well.
So I look around for a final test. Not seeing anything obvious, I have a flash of insight. I weigh about 75 kg. So I sit with my feet in the bucket of hot water, put the thermometer in my mouth, and wait for my head to heat up. This experimental setup is shown in Figure 1 above.
After all, simple physics is my guideline, I know what’s going to happen, I just have to wait.
And wait … and wait …
As our thought experiment shows, simple physics may simply not work when applied to a complex system. The problem is that there are feedback mechanisms that negate the effect of the hot water on my cold toes. My body has a preferential temperature which is not set by the external forcings.
For a more nuanced view of what is happening, let’s consider the second example, a river. Again, a thought experiment.
I take a sheet of plywood, and I cover it with some earth. I tilt it up so it slopes from one edge to the other. For our thought experiment, we’ll imagine that this is a hill that goes down to the ocean.
I place a steel ball at the top edge of the earth-covered plywood, and I watch what happens. It rolls, as simple physics predicts, straight down to the lower edge. I try it with a wooden ball, and get the same result. I figure maybe it’s because of the shape of the object.
So I make a small wooden sled, and put it on the plywood. Again, it slides straight down to the ocean. I try it with a miniature steel shed, same result. It goes directly downhill to the ocean as well. Simple physics, understood by Isaac Newton.
As a final test, I take a hose and I start running some water down from the top edge of my hill to make a model river. To my surprise, although the model river starts straight down the hill, it soon starts to wander. Before long, it has formed a meandering stream, which changes its course with time. Sections of the river form long loops, the channel changes, loops are cut off, new channels form, and after while we get something like this:
Figure 2. Meanders, oxbow bends, and oxbow lakes in a river system. Note the old channels where the river used to run.
The most amazing part is that the process never stops. No matter how long we run the river experiment, the channel continues to change. What’s going on here?
Well, the first thing that we can conclude is that, just as in our experiment with the steel block, simple physics simply doesn’t work in this situation. Simple physics says that things roll straight downhill, and clearly, that ain’t happening here … it is obvious we need better tools to analyze the flow of the river.
Are there mathematical tools that we can use to understand this system? Yes, but they are not simple. The breakthrough came in the 1990’s, with the discovery by Adrian Bejan of the Constructal Law. The Constructal Law applies to all flow systems which are far from equilibrium, like a river or the climate.
It turns out that these types of flow systems are not passive systems which can take up any configuration. Instead, they actively strive to maximize some aspect of the system. For the river, as for the climate, the system strives to maximize the sum of the energy moved and the energy lost through turbulence. See the discussion of these principles here, here, here, and here. There is also a website devoted to various applications of the Constructal Law here.
There are several conclusions that we can make from the application of the Constructal Law to flow systems:
1. Any flow system far from equilibrium is not free to take up any form as the climate models assume. Instead, it has a preferential state which it works actively to approach.
2. This preferential state, however, is never achieved. Instead, the system constantly overshoots and undershoots that state, and does not settle down to one final form. The system never stops modifying its internal aspects to move towards the preferential state.
3. The results of changes in such a flow system are often counterintuitive. For example, suppose we want to shorten the river. Simple physics says it should be easy. So we cut through an oxbow bend, and it makes the river shorter … but only for a little while. Soon the river readjusts, and some other part of the river becomes longer. The length of the river is actively maintained by the system. Contrary to our simplistic assumptions, the length of the river is not changed by our actions.
So that’s the problem with “simple physics” and the climate. For example, simple physics predicts a simple linear relationship between the climate forcings and the temperature. People seriously believe that a change of X in the forcings will lead inevitably to a chance of A * X in the temperature. This is called the “climate sensitivity”, and is a fundamental assumption in the climate models. The IPCC says that if CO2 doubles, we will get a rise of around 3C in the global temperature. However, there is absolutely no evidence to support that claim, only computer models. But the models assume this relationship, so they cannot be used to establish the relationship.
However, as rivers clearly show, there is no such simple relationship in a flow system far from equilibrium. We can’t cut through an oxbow to shorten the river, it just lengthens elsewhere to maintain the same total length. Instead of being affected by a change in the forcings, the system sets its own preferential operating conditions (e.g. length, temperature, etc.) based on the natural constraints and flow possibilities and other parameters of the system.
Final conclusion? Because climate is a flow system far from equilibrium, it is ruled by the Constructal Law. As a result, there is no physics-based reason to assume that increasing CO2 will make a large difference to the global temperature, and the Constructal Law gives us reason to think that it may make no difference at all. In any case, regardless of Arrhenius, the “simple physics” relationship between CO2 and global temperature is something that we cannot simply assume to be true.
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If you want to get a good picture of CO2 and water vapor absorption issues, check out WWUT article dated: 21 06 2008, Title: “A Window on Water Vapor and Planetary Temperature – Part 2”
Note that for the Earth’s escaping energy transfer analysis these graphs would be better plotted as a function of frequency rather than wavelength and limited to the range of 6 to 20 microns (15 to 50 THz).
As the width of the carbon dioxide band increases, the temperature must increase to force more heat through the narrowed open window. The heat flow is proportional to the fourth power of the absolute temperature. We are not considering the parallel effect of convective heat transfer. We are not attempting to account for changes in cloud cover. This is not a simple problem.
“MrAce (12:47:32) :
[…]
Since CO2 is located high in the atmosphere where it is colder, it radiates less intense then the earth”
Are you sure you understand the concept of absorption and reradiation?
cthulhu,
“Simple physics alone show significant warming from a doubling of co2.”
If by simple physics you are referring to the Stefan-Boltzman equation then I’m sorry, but your statement is just plain wrong: simple physics alone show an INSIGNIFICANT warming – just 1.2C.
This can be seen by doing the calculation F = sigma.T^4 and substituting 288K for the pre doubling temperature and the known insolation for F, then adding 3.7 to that and solving for dT.
No, the fact is the simple physics gives a putatively low sensitivity, which is why the models depend on the multipliers of positive feedbacks to give sensitivites that are significant.
Bart (12:44:34) :
“The point of the post is to provide a basis by which non-technically oriented people may grasp that complex systems behave in anti-intuitive ways. It is not that the climate scientists do not understand that they are dealing with a complex system, it is that they are selling it to lay people as being simple and straightforward, when it is not.
Was that really so difficult for you to understand?”
No, the point I see in this article is to explain that complex systems behave in anti-intuitive ways, and then to imply that climate scientists don’t understand this, something that you have clearly fallen for.
Climate scientists are not “selling” anything. That’s the skeptic party line and is silly. Climate scientists are doing science. If you can’t understand the science, that’s your problem. If you can’t understand the science, and then have the gall to take a side in the debate, then that’s just wrong.
But I’ve never seen anyone, anywhere, on the warming side of the debate claim that it was simple or straightforward. If anything, it’s the constant denier arguments that try to oversimplify things. That’s merely a convenient (for you) misrepresentation of things to try to score points.
I myself have studied the climate science in detail, and there is absolutely not a single aspect of it that I would label as simple, and I don’t believe I’ve ever seen any of the climate scientists, or anyone outside of the denialsphere, label it as such.
As far as your pejorative question, “…was it really so difficult?” When you understand the science as well as I do you will earn the right to ask that question, and to cop that attitude. Until then, please keep studying.
ThinkingBeing: “Secondly, they can “backcast” things, and doing so is one technique used to validate the models.”
Can you please point me to an article or study that demonstrates the backcast capability of models?
cthulhu: “If we want to get no warming from a doubling of co2 we require the forcing to be completely offset by an increase in albedo, possibly by reducing sunlight reaching the Earth. But such an increase in albedo and reduction in absorbed sunlight is a climate change causedin itself. Either way doubling co2 causes significant climate change. There’s no way of getting around this and it’s why co2 is such an issue.”
“Such an issue”. Sorry, what you just described is hardly anything approaching the doom and gloom predictions used to justify massive climate research funding and ‘solutions’ that would clearly bring our economy to a screeching halt. So now that ‘global warming’ is apparently no longer the issue with our PUNY addition of CO2 as you seem willing to concede, then the extent of our culpability for your ‘significant’ ‘climate change’ would amount to ~5% more rainfall in tropical rain forests than there would have been without any humans around, (or without any termites or volcanoes around, etc.). Oh my! That’s a disaster! The tree frogs might get too wet!
The population at large was scared into believing that our climate was headed for some kind of ‘tipping point’, runaway global warming that was going bring disease, droughts, floods, pestilence, starvation, mass migrations and terminal acne but look what reality is bringing us since those dire predictions were made while CO2 just kept rising- nothing of the sort. Reality appears to be a very stable climate with strong negative feedbacks that were not anywhere near adequately represented in the models used to scare everybody thus making them …. WRONG!
Here’s my equation: More CO2 = more plant life = more animal life = GOOD!
Willis says:
See Dimethylsulfide Emission: Climate Control by Marine Algae? for more info.
“MrAce.
Since CO2 is located high in the atmosphere where it is colder, it radiates less intense then the earth, thus resulting in an greenhouse effect.”
So the warm CO2 molecules emit a broad emission spectrum and the cold CO2 molecules can only absorb a very narrow set of wavelengths. The colder the ones at the top, the less of the spectra of the warmer ones they can absorb.
ThinkingBeing:
“Climate scientists are not “selling” anything. That’s the skeptic party line and is silly. Climate scientists are doing science. If you can’t understand the science, that’s your problem. If you can’t understand the science, and then have the gall to take a side in the debate, then that’s just wrong.”
I think you’re being totally naive with this statement. If anything, we’ve learned that many in the “inner circle” of the climate science community have been more involved with propaganda and nudging numbers in ways to prove their specific points — they act much more like eco-activists than objective scientists.
*******
ThinkingBeing (13:50:32) :
No, I never said any such thing and you know it. First, they can’t forecast anything, but they can reliably forecast an increase in temperatures due to CO2. Secondly, they can “backcast” things, and doing so is one technique used to validate the models.
***************
You have absolutely no proof that GCM correctly model the climate. If you believe they backcast temperature for example, the proxy-generated temperatures have been shown to be flawed as have even the instrumental records. Your precious models didn’t even forecast the recent flatness of temperature for the past several years. Your supercilious attitude 1) does not mean you are of a superior intelligence and 2) does not prove your case. You appear to be nothing more than a windbag.
“…I am now appalled that I ever bothered to post a comment on your post. It’s beneath me.”
Rather like the virgin in the back seat of the VW, ThinkingBeing refuses at very great length.
Re DirkH (13:47:16) :
“1.) Current GCMs don’t include clouds”
Wrong
re Vincent (14:10:23) :
1C warming is not insignificant! It’s more than the total warming over the entire 20th century! If co2 causes that much warming then it certainly will be the dominant driver of climate on these timescales.
ThinkingBeing (14:16:13) : “Climate scientists are not “selling” anything.”
—–
Yeah, a very large number of them have just been sucking away on over 30 billion of our tax dollars for the last 20 years so we shouldn’t be all that surprised that they claim that there’s still a ‘problem’ that requires their continued services. Pull the plug on climate research and the ‘problem’ will disappear overnight.
http://joannenova.com.au/2009/07/massive-climate-funding-exposed/
“ThinkingBeing (14:16:13) :
[…]
Climate scientists are not “selling” anything. That’s the skeptic party line and is silly.”
Google Hansen Storms Of My Grandchildren if you want to see your argument swiftly obliterated, thank you for your time, it was fun to talk to you.
Louis Hissink (13:53:15) :
: But use solar powered thermal drivers then you have the mess associated with chaotic behaviour associated with the Navier-Stokes equations. And of course the obvious fact that during night time the solar driver disappears, raising the question of how a hurricane could maintain its state.
Condensation eg
Condensation-induced dynamic gas fluxes in a mixture of condensable
and non-condensable gases
A.M. Makarieva ∗, V.G. Gorshkov
Physics Letters A 373 (2009) 2801–2804
It is shown that condensation of water vapor produces dynamic instability of atmospheric air and induces air circulation that is characterized by observable air velocities and persists independently of the magnitude of horizontal temperature gradients.
Condensation-induced kinematics and dynamics of cyclones, hurricanes
and tornadoes
A.M. Makarieva ∗, V.G. Gorshkov
Physics Letters A 373 (2009) 4201–4205
A universal equation is obtained for air pressure and wind velocity in cyclones, hurricanes and tornadoes as dependent on the distance from the center of the considered wind pattern driven by water vapor condensation. The obtained theoretical estimates of the horizontal profiles of air pressure and wind velocity, eye and wind wall radius in hurricanes and tornadoes and maximum values of the radial, tangential and vertical velocity components are in good agreement with empirical evidence.
Introduction
In this Letter we describe how dynamic fluxes are generated
in a gas mixture containing a condensable gas in the presence of
a vertical temperature gradient in the gravitational field. We will
consider water vapor as condensable gas to retain the physical
linkage to the terrestrial atmosphere. Condensation leads to disappearance
of water vapor from the gas phase, which produces drop
of local air pressure and creates a wind-inducing pressure gradient
force that is proportional in magnitude to the amount of water vapor
that undergoes condensation. In the presence of a sufficiently
large vertical temperature gradient the vertical distribution of saturated
partial pressure pH2O departs significantly from the static
equilibrium; at any height pH2O is over five times larger than the
weight of water vapor column above this height [1]. For this reason
practically all water vapor ascending in the atmosphere undergoes
condensation. The volume-specific store of potential energy available
for conversion into kinetic energy of air movement can thus
be estimated as the value of partial pressure pH2O of saturated water
vapor to a good approximation.
Climate scientists are not “selling” anything. That’s the skeptic party line and is silly. Climate scientists are doing science. If you can’t understand the science, that’s your problem. If you can’t understand the science, and then have the gall to take a side in the debate, then that’s just wrong.
I must object to this.
I am not saying that pro-AGW climate scientists do not genuinely think they are right. But to say that there is no “selling” going on is in direct contradiction with the clearest of evidence. It is the most blatant, in-your-face sales job I have ever been subjected to in all my life.
Furthermore, laymen, “non-expert” as well as “expert” (those on the receiving end of the extraordinarily intense sales pitch), which include not only nearly all common voters but nearly all legislators as well, are the ones who will decide policy. They will take a side in this debate whether you consider it “just wrong” or not.
It is the responsibility of the climate scientists (and many other practitioners of related disciplines), to be our “expert witnesses”. And to do that they must first scrupulously follow the rules of scientific method, with an emphasis on full disclosure of data and open method/source. Second, they must explain to the lay public their conclusions, clearly and concisely, including a dispassionate assessment of certainty/uncertainty. After that, policy is out of the hands of the “experts” — and the vote of a Hansen or a Lindzen counts no more than your vote or mine, nor should it.
Yes, common citizens should try to become informed, but the primary onus of the explanation is upon the experts. And the experts need to be playing it straight.
Scientists too often forget that they are no more competent to determine policy than legislators/voters are to determine science.
Re Mike M (14:20:33) :
“Reality appears to be a very stable climate with strong negative feedbacks ”
No model has ever shown strong negative feedbacks, and the history of Earth’s climate defies it. If there were strong negative feedbacks in climate, the climate would barely change at all.
And don’t put words in my mouth – I never said ‘global warming’ was no longer an issue. In fact I think such conclusion is reckless given the state of the science.
Oh this brought back happy memories.
Years ago a friend purchased a book for me entitled “Ideas and Opinions” by Albert Einstein.
I immediately read it cover to cover.
One of the articles I found fascinating was the chapter entitled “The Cause of the Formation of Meanders in the Courses of Rivers and of the So-Called Bayer’s Law”. This article was first read to the Prussian Academy, January 7, 1926. Published in the German periodical, Die Naturwissenschaften, Vol. 14, 1926.
You may read a portion of this paper at http://www.searchanddiscovery.net/documents/Einstein/albert.htm
At the time I first read the article I was impressed by the notion Einstein worked on a lot of interesting questions. Who would have guessed a seemingly mundane matter as the meanders of streams would attract the attention of Einstein?
As the article points out, meandering of streams is not a matter of simple physics. It is a challenging enough matter to have attracted Einstein.
I think about the source of meandering streams everytime I fish the North Platte River by Walden Colorado. I take advantage of the oxbows to entice brown trout with drifting nymphs.
ThinkingBeing (13:50:32) :
Wow, considering the disparaging language in your posts, you must be very angry and unsure of yourself.
Anyway,
“No, I never said any such thing and you know it. First, they can’t forecast anything, but they can reliably forecast an increase in temperatures due to CO2. Secondly, they can “backcast” things, and doing so is one technique used to validate the models.”
Er, the CO2 levels have continued to increase but warming hasn’t for about 15 years, now. NONE of the models show any such thing. Why?
Can we now refer to him as TrollingBeing ?
ThinkingBeing (14:16:13) :
“Climate scientists are not “selling” anything. That’s the skeptic party line and is silly. Climate scientists are doing science.”
Even when they work for an oil company?
Or when they offer conflicting conclusions, they aren’t “real” scientists?
Any actual news on what is stirring in the world of the IPCC, Mann and the disciples of the Warming Cult? Any public flogging, hanging, stepping downs or the like?
ThinkingBeing (14:16:13): I myself have studied the climate science in detail, and there is absolutely not a single aspect of it that I would label as simple, and I don’t believe I’ve ever seen any of the climate scientists, or anyone outside of the denialsphere, label it as such.
Indeed. I agree. Still simulating the climate may be impossible. How do we know that it is not impossible?
It doesn’t take a climate scientist to see there is something funny coming out of CRU, GISS, etc. I doesn’t take an oil-money-funded conspiracy to get people to want to understand what happens to the raw data. An example is the pitifully small, if any, UHI corrections one can see by looking at what data is made available. Heck, I’ve driven through Dallas and had the thermometer on the dash go from 94 degrees 10 miles east to 104 degrees downtown and back to 94 degrees ten miles north. I have access to real time data from a frequently calibrated met tower at a nuclear power plant and I compare that to what GISS says about the temperature in a small city 15 miles away. Guess what? The city’s temperature compares more closely to the temperature of the intake air on the aux building roof than to the temperature at the met tower a thousand feet away in a green field. And that aux building, with a black tar roof, is nestled nicely amongst cooling towers rejecting about 4000 MW to the atmosphere.
Seeing these kinds of things and being curious causes you go to various websites and start trying to square what some scientists are saying with the realities you’re observing and you find out you’re being equated with a mass-murderer just for being curious, without ever having taken a dime from big oil.
Then you see where they say we have to get rid of the MWP and poof it’s gone. Then you see were the temperatures in the 30’s have to be lowered and poof, they’re lowered. Then you see something like the adjustments made to the Darwin temperature record and you see zealots come on here and defend that. Then you see zealots talking about the ice being nearly gone and you start looking around and find that it’s pretty much just like it always was.
Some things the scientists ought to ask themselves: Climate might be sensitive to this and that but how sensitive are economies to the remedies. How many billions will die if climate panic triggers global economic collapse (which it won’t because 1/2 of the world is China and India and they aren’t buying the snake oil)? Who’s going to fund a scientist’s life work in a post-industrial world?