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.
Sponsored IT training links:
Download RH302 questions & answers with self paced 70-270 practice test to prepare and pass 646-985 exam.
Very interesting article. It sounds like Chaos Theory. Is that the same thing? Its strange that we don’t hear more about it in climate discussion. Earth’s climate is certainly complex enough to qualify.
That is the point where you hand the person a pad of paper and a pencil and say:
“Oh could you please write that simple formula down so I can predict next weeks weather?”
Larry
@Andy Y (22:11:04) :
“Roger Sowell, ummm…. a heat transfer system IS a flow system. Come on man, that’s simple thermodynamics. So whatever criticisms you thought you were levying against Willis are completely unfounded and dumb. Additionally, no where in the entire commentary did he mention anything about steady state, so why you’re bringing that up is even more bewildering.”
The heat does indeed flow…the molecules do not in conductive heat transfer. In convective heat transfer, both heat and molecules flow. In radiative heat transfer only the heat flows. Simple thermodynamics. A river flows. Usually. The point, as you missed it, is that the earth does not flow. It orbits, it revolves, it wobbles a bit, but no flowing. Simple orbital mechanics.
As to steady state, it was implied in the article.
@anna v
“Several problems with this. First, rivers are non-steady-state, that is, they wax from high flow (Spring runoff), then ebb to low flow (late summer). The shape of a river is created much more by the high flow events than other flow regimes. Anyone who has lived near a river knows this. ”
Think again? What area dries out and how much and how hard during low flow should be equally significant to the the high flow effect, imo. All it takes is a tree trunk cutting the flow, and how the tree is snagged depends on how the previous bed dried etc. etc.”
The high flow effects are orders of magnitude greater than the low flow, silting or deposition effects. Deposition creates soft areas that are readily eroded (pose virtually zero resistance) during flood flow. We mine ancient river beds for sand, gravel, and clays. The rivers did a fine job of separating the larger particles from the smaller ones.
As an aside, during high flow periods of the Colorado river through the Grand Canyon, one can hear giant boulders smashing into the riverbed as they are carried along by the flow.
@Paul Hildebrandt (03:06:23) :
“Actually, the earth is flowing, and has been since Day 1. It’s called Plate Tectonics. Although not flowing at incredible speeds, the continents and oceanic basins are moving on a conveyor belt of sorts. Also, if you want to break it down even further, colliding continents are pushed up, oceanic basins are subducted down, rock is eroded and flows downstream as sediment, mass earth movements, and even in the atmosphere as dust. So, I would reevaluate your statement in light of the above. “
Plate tectonics indeed move the continental plates, but they end up on the earth, no flowing. What plate tectonics do over long periods, in relation to climate changing, is create mountains that change the wind patterns, form glaciers (if the mountains are sufficiently high e.g. Himalayas), create river basins, create earthquakes and tsunamis, and have an effect on ocean currents. Plate tectonics are not fast events as you mentioned. Mountain building is very slow, while a volcanic eruption is very quick.
@Marcus (03:22:41) :
“When the only tool you have is a hammer, every job looks like a nail!”
When one is a master builder with a complete set of tools, it is rather easy to choose the right tool for the job.
nanny_govt_sucks (06:01:34) :
Perhaps you can explain how high interest rates which induce people to save which makes more capital available is a “negative”? Perhaps you can explain how low interest rates which induce people to spend and makes less capital available is a “positive”?
How about I take a shot at it?
Money is the circulating fluid in the financial system. For a healthy economy we want the money circulating as fast as possible, with the caveat being that with too much flow the system gets leaky, unstable, money gets lost and diverted to somewhere else than where it should be (credit defaults prevent money from returning to lenders, etc).
When interest rates are low, people are more willing to borrow, that’s the important thing. As long as the supply is there, that is other people are willing to lend (invest), then the flow increases, which is normally positive (see caveat). The interest paid on savings may be low, but then people with money to invest find other places than banks to put their money into the system while searching for greater returns (more flow). Companies have money to start up, to expand, the economy grows.
When interest rates are up, the flow is restricted. People are less likely to borrow, thus less money is circulating in the system, there is a reduced flow rate. The economy suffers. If a particular industry has an expected rate of return of 8%, and the banks are paying 9%, people would rather put their money in the bank. So the industry does not get money it could use to expand operations, to grow, and if it hits a tough spot where it needs to borrow money to survive, then it may die because the money is not there. As interest rates go up the economy slows in growth, stagnates, and can even shrink. Thus high interest rates are a negative.
Depending on what imbalances are affecting the system, like politics and taxes and world events that affect investor confidence, there might not always be a straightforward high-negative low-positive relationship. There are a chaotic elements involved, and a lot more complexity. But overall the relationship holds.
scienceofdoom (21:25:35): Anyone know of less certain people than realclimate who look into the subject of climate as chaotic and any papers on it?
REPLY: “weather” is known to be chaotic. Climate is a long term collection of weather events, so it stands to reason that it is also chaotic, but on a longer, slower time scale. – Anthony
Exactly! To argue that the climate is chaotic on short timescales only is clearly nonsense and violates the well documented¹ inverse power law scale invariance in our climate that indicates long-range correlations. Lorenz (1963) conclusion concerning the atmosphere that “prediction of the sufficiently distant future is impossible by any method” remains unrefuted.
¹Chaotic Climate Dynamics (2007) Dr. Selvam, Indian Institute of Tropical Metrology.
Thar she blows
If we boil and burn up as predicted, the need for new bridges is over.
Anders L. (07:13:06) :
“Natural systems do not “actively strive” to achieve anything.”
I’ll notify Dr. Clausius immediately.
leftymartin (22:55:00) :
This is excellent reinforcement of my own inchoate thoughts, to wit: The Earth must be in an operational regime which is difficult to get out of, else it would have gotten out of it long ago. Such a state is reached when there is active resistance, i.e., negative feedback, keeping it there.
tom (21:09:47) :
“…overeating will lead to obesity and starvation will lead health problems and possibly death… a free market economy … responds positively to low interest rates and negatively to high interest rates.”
What will the effect of weight be if you raise your caloric intake 3%, i.e., in a 2000 calorie diet, by 60 calories (about the content of an apple)? How about if you lower interest rates by 3% of, say, 6%, i.e., by 0.18% in absolute terms?
When we start to delve deep into the physical thermal
properties of the different metal cubes the author used
in his analogy we loose the basic point.
That seem to be an intentional diversion of his point by
some here.
It’s not important that a block of, say, aluminum would
heat up at a different rate than a block of iron.
But that they BOTH heat up. And a human body doesn’t.
The body is dynamic while the blocks of metal are static.
That, I believe , is the point.
The path of a falling snowflake could be precisely predicted
using mathmatics but the data set to do that would be astronomically huge. The same with the climate.
The interaction of variables upon all other variables,
even if all are known (giggle here), produce the same krazy-large data sets.
So then we use “proxy” data sets where static data is used
in place of actual dynamic data. (more giggling here).
Science teadhes humility in that the more you know, the more
aware of your are of your own ignorance.
P Wilson (04:17:57)
Its like a throwback to the 1930’s when communism and fascist ideologies put the blame on man as the great fault of civilisation, so people ought to be bent to the ideologies of political extremes to save them and civilisation.
That seems to be the way its developing as an ideology
Firstly, It seems to me to be the otherway around. It’s the communists that got into the political lobbying groups masquarding as “charities” e.g Greenpeace, WWF, etc. that are pushing this.
Secondly; IMO Communism and Fascism are pretty much twins. Mussolini was Secretary of the Italian Socialist Party before he became a Fascist. The Nazi group was named the National Socialist Party. In UK the British Union of Fascists was form by Oswald Moseley, who was a Cabinet Member in a Labour Government. They are of a muchness.
Apparently they are having some problems in Ireland with burst water pipes and water mains. This is one of those circumstances where temperatures a few degrees below normal costs millions of dollars but temperatures a few degrees above normal are tolerated without problem.
Cooling is worse than warming.
JonesII
The hypothesis is dead, but don’t expect governments and treehuggers to stop playing the music. Like the band on the Titanic, they’re gonna keep on playing while the ship sinks.
sustainableloudoun (05:38:25) :
“First, the ‘author’…”
“Then the ‘author’…”
“…lest the ‘author’…”
“…the ‘author’…”
Ok, which is it? Are you alleging that the author of this article is someone other than listed, that the article has no author, or that you are incredibly incompetent at the use of apostrophes to ‘denote sarcasm’? See what I did there?
I’ve said knowledge is like a circle: As the diameter of your knowledge increases, the circumfrence of your ignorance enlarges that much more.
“”” John F. Hultquist (20:46:58) :
All this ‘simple physics’ makes me think of the simple formula for the area of a circle. Area is equal to pi times the radius squared. Many people have used this simple formula. Not many can derive it or prove that it is true.
But the simple GHG idea is even more difficult. When someone says it is simple, just say “Prove it.” Ask them if the process works for CO2 why doesn’t it work for O2 or N2, both of which are major components of the atmosphere. Yes, some people do know what is going on but most have no idea, especially those out in the snow chanting ‘turn off the heat.” And if it is simple physics, why must there be some unknown ‘forcing’ to make it work. Do most of the people know about this or have any idea how quickly simple physics gets astoundingly complex?
As for Willis’s example the concepts for meandering rivers have been shown for years in earth science classes, thus providing such a demand that the “stream table” has been commercialized:
http://wardsci.com/category.asp?c=890&bhcd2=1261975346
and an interesting example:
http://scienceblogs.com/highlyallochthonous/2009/10/how_to_build_a_meandering_rive.php
For many years Washington State University in Pullman had a RR-boxcar size one inside a building. Maybe they still do. “””
Well proving the area of a circle, is fairly trivial if one is skilled in the integral calculus; but not so simple if that more advanced level of mathematics is prohibited. But then not so difficult either if one is good at geometry.
Simply divide the circle up into a large number of pi sections (pun intended); might as well make them all the same, and make the number of them very large. So the total circumference of the circle is still 2.pi.r, one may almost say by definition of pi; well one definition.
So now you take every other pi section and reverse it, and they all pack together into a rectangular block, with somewhat scalloped long sides, which is why we make the number large. Each long side contains half the circumference of the circle, so that is pi.r, and the short side of the block is simply the radius r , and simple geometry tells us the area is now r x pi.r, or pi.r^2. qed.
And if you don’t like that definition of pi, then you can always use:-
pi = -sqrt(-1).Ln(-1); which although correct, is not calculable.
As for having a RR box car inside a building; you should visit “The House on the Rock.” which is out in the boonies in Wisconsin. Why the rock is there is about as mysterious as why Ayre’s rock exists in Australia. Now the house on the rock is more like the house IN the rock; well it’s hard to decide which parts of the house are in the rock and which parts of the rock are in the house.
But more importantly; around the base of the rock, there are extraneous buildings; some quite sizeable. The one that comes to mind contains three simply giant pipe organs, all of which can be played simultaneously from one of a handful of equally impressive consoles; one of which contains about 21 keyboards, not counting the pedal board. Down on the floor, sort of in the middle of the building, there is a giant triple expansion steam engine, out of some ancient steamship. But the piece(s) de resistance, are the dioramas on the inside walls of the building; some of them quite large; as in complete railway locomotive engines just stuck on the wall of the building as if hanging on a thumbtack. The original owner of the house on the rock, one might say was the archetypical nut case.
Phil. (07:21:49) :
“Water flowing downhill tries to get there as fast as possible which would mean following a brachistochrone and this is supposed to tell us something about the response of the climate to CO2?”
Phil, since you seem to know so much about everything, can you please explain why cutting through an oxbow is not a stable approach to making a river’s path shorter? Or is the whole claim about the river wrong?
I await your enlightening response.
From: Ganymede 6642
That the physics of climate change is uncertain is already well summarised by the IPCC in its 2007 report (The Physical Science Basis). The table on page 32 of the Technical Summary gives a 90% confidence interval for the global mean radiative forcing of all anthropogenic agents of 0.6 – 2.4 watts per square metre.
This whole post is therefore somewhat redundant.
a) Did you miss the smile/wink emicon? (Yes)
b) Re-read the comment in context of my original post.
c) Are you unaware of geological processes which level otherwise uneven/sculpted areas near rivers left over from the glacial era? (I think so.)
I offered Battle Creek as an example since it was an area I had observed/studied this ‘effect’.
.
.
As for meandering rivers; the same system works quite well whether the river water is poured over the land or over the ocean. Giant rivers meander all over the oceans, and given how cheesy the ocean is compared to the Grand Canyon rocks, they switch course someone more readily.
That alone, makes monitoring the earth’s temperature, by measuring the ocean water temperatures, an exercise in futility. Return in your taxpayer grant fed survey ship, next year to the same GPS co-ordinates, and you will likely be in quite different water from what you were in last year.
And if you succeed in somehow extracting an average temperature; it will tell you exactly nothing about how and where those ocean rivers will wander to next.
To Roger Sowell:
But the main components of climate/weather are the atmosphere and the oceans. They flow on a rigorous and constant basis and transport huge amounts of heat in all directions on the globe.
Add to these the main driver–energy from the sun in various forms, which can also be considered a flow.
If “it’s simple physics”, why not make a greenhouse at the Earth’s surface, fill it with N2 and O2 only and a pool of H2O large enough to saturate the enclosed atmosphere, freeze over, and so on, then measure the temp. each hour x 24 and say that’s the temp. for that place on Earth “unforced” by CO2, for each hour?
Because the Oceans do the same thing for the Earth’s “Greenhouse” in regard to water vapor.
Then add some differing amounts of CO2 and repeat. Repeat for every “grid cell”, and viola we have just figured out everything we need to know about water vapor’s effect and CO2’s effect on temperatures. And about what the temperature of each grid cell “should” be.
I don’t even want to think about what’s wrong with my simple physics experiment, but my problem with the ghg effect is that I have no idea why, if the effect is supposed to work the way Climate Scientists say it works, water vapor hasn’t already produced it’s maximal ghg effect, reached its own tipping point, and why CO2 would do anything at all to change the effect of water vapor, which should have already burned up the Planet.
In the TAR section on ghgs water vapor ~”is not discussed”. I still can’t believe it actually said that and might have to check it again, except that I didn’t get a screen shot, so things might have been “adjusted”.
RECORD COLD WATCH FOR UK
Our reader UK mates here at WUWT may want to cozy up with your lassies in the days ahead.
Joe Bastradi forecasts snowy weather for the UK in the days ahead, followed by an Arctic blast. That means clear nights in combination with snow cover could send the mercury a falling.
http://www.accuweather.com/world-bastardi-europe-blog.asp?partner=accuweather
Plato at CA posted the following: Met Office slap-down
http://www.telegraph.co.uk/topics/weather/6901002/Warnings-of-more-snow-for-Britain-as-predictions-of-mild-winter-fall-flat.html
The accuracy of the Met Office is truly astounding. I’m just so amazed that one could miss the barn so often. This is comedy.
“”” Roger Sowell (09:11:34) :
@Andy Y (22:11:04) :
“Roger Sowell, ummmThe heat does indeed flow…the molecules do not in conductive heat transfer. In convective heat transfer, both heat and molecules flow. In radiative heat transfer only the heat flows. Simple thermodynamics. “””
Well not so fast Roger. I agree with you that in convection, both “heat” and molecules flow, while in conduction, only heat “flows”.
But in radiation, there is no “heat” to begin with, and there is no transfer of heat with the flow of the photons; energy yes, but heat no, since there is no molecular matter involved in the transport of photons.
This article is ridiculously disingenuous. To start, it implies that climate science applies “simple physics” with no consideration for complexity, like a child thinking that anything that is brown is chocolate. It’s not true, and you know it. You belittle all of climate science by acting like scientists are oh so silly and foolish to not see the obvious that you and yours can see.
In particular, it is a flat out lie that the models assume a relationship that results in a 3C change. They “assume” a large and complex system of physical relationships, and are allowed to randomly run their course in thousands of different iterations, but in the end the 3C pops out at the end, no matter what… much like the water, no matter how it meanders down the slope, winds up at the bottom in the end.
Your Constructal Law analogies are improperly applied. The climate models do behave just as you describe, just as does the real climate. In fact, your Constructal Law analogy is a perfect argument for why deniers should stop already with the “the climate is cooling” rant. Any “cooling” you see in a short time span is just the meandering of a system that is never nicely in equilibrium.
Third, it is arguable as to whether Constructal Law actually applies to the climate. It may, but there are differences. It may apply to weather patterns, to air flows and water circulation, but not necessarily to heat exchange as a whole. In particular, Constructal Law applies to more structured systems than the climate, not less. A river flowing through a landscape, or a tree growing or a traffic pattern is in no way as complex and multidimensional as a climate system.
Fourth, your river analogy is more properly applied by changing a relevant factor between two runs, such as the slope of the sled, or the rate of water being poured. Those factors would most certainly result in certain predictable changes (more force to overcome friction results in less meandering, or at least faster changes in the direction of flow). In fact, if the rate of flow is increased enough, Constructal Law will cease to apply. The water would cut straight through and down without enough friction or cohesive substance to deflect it.
Fifth, and this to me is the big point… the entire argument does come down to climate sensitivity. Deniers think there is going to be some magical, impossible to predict negative feedback that forces the climate to stay right where you want it to, within a 1C range. This is, in fact, equivalent to your river analogy. Deniers think that the river must flow straight downhill, that even if a pebble slightly alters the river’s course, the water will overcome it because it wants to flow straight downhill. It can’t possibly vary by more than 1C.
The question is… how stable is the climate? You want to believe that it will stay within one degree of a norm, and it will do anything and everything possible to stay there. You can’t offer an actual mechanism, with proof, that it will happen. You just keep saying it will. But experience and science says the opposite… the climate won’t run away, but the range within which it will vary is larger than you and yours are willing to admit (funny how you’ll argue that the MWP exists and was warmer than today, but that at the same time the climate is too insensitive to vary by 3C due to CO2).
Really, to properly use your river analogy, what climate scientists are saying is that, despite all of the perturbations the flow may assume, it will try to head downhill and eventually reach the bottom. The statement that “CO2 will raise temperatures by 0.5C, which will increase water vapor and thereby raise temperatures in total to 3C” is equivalent to the sled/river statement that “the water will reach the bottom eventually, no matter what else goes on.”
The denier position is equivalent to saying that the system is so convoluted and unpredictable that the water will find a way to pool and stop on the way, or even work it’s way back up, so it never reaches the bottom, because equilibrium states that the water “wants to stay where it is.”
So, no, your Constructal Law analogies are bogus. They may apply to climate science, but not in the way that you’ve presented them. You’ve done a very artful job of confusing a lot of people into thinking what they already want to believe, and what you want them to believe.
The final, ultimate question is, can an artificial change in the basic parameters of the system due to an unexpected external influence, i.e. a 0.5C forcing due to CO2 with a cumulative 3C forcing due to water vapor, have a noticeable influence before the system stabilizes in a new equilibrium? Constructal theory says nothing one way or the other about whether that value is or is not a reasonable prediction, because it applies to how the system works within some degree of equilibrium, not how two systems will compare when the parameters that influence that equilibrium are changed (i.e. more CO2, or a different tilt to the earth, or any other factor that has a sudden unexpected change on climate equilibrium).
In fact, Paleoclimatology tells us that 3C is quite within the range of variations one might expect, and possibly even a low estimate.
The bottom line is that deniers want to believe that we will be saved by magic, that somewhere Mother Nature has a secret negative feedback waiting to save us from ourselves. “Alarmists” don’t want to trust to magic.
The real bottom line? Your statement that “…there is no physics-based reason to assume that increasing CO2 will make any difference to the global temperature, and the Constructal Law gives us reason to think that it may make no difference at all.” is a flat out lie. The physics based reason is very simple to understand and would require an act of God to alter, and deniers only offer magic as their main argument that it is wrong.
Good idea to present the evidence in some articles in terms the public can easily read and understand.
I think Joe Bastardi ought to have a guest post here at WUWT.
Read the link I provided above.
It’s going to be 2 weeks of hell for warmists! My favourite Joe qoate:
“…but just as climategate woke some up to what some of us already knew, now the weather is piling on.”
Joe, thanks for making my day!
REPLY: Joe’s work contract for AccuWeather Inc prevents him from doing this I think .-A