Guest Post by Willis Eschenbach
Once again, the crazy idea that downwelling longwave radiation (DLR, also called infra-red or IR, or “greenhouse radiation”) can’t heat the ocean has raised its ugly head on one of my threads.
Figure 1. The question in question.
There are lots of good arguments against the AGW consensus, but this one is just silly. Here are four entirely separate and distinct lines of reasoning showing that DLR does in fact heat the oceans.
Argument 1. People claim that because the DLR is absorbed in the first mm of water, it can’t heat the mass of the ocean. But the same is true of the land. DLR is absorbed in the first mm of rock or soil. Yet the same people who claim that DLR can’t heat the ocean (because it’s absorbed in the first mm) still believe that DLR can heat the land (despite the fact that it’s absorbed in the first mm).
And this is in spite of the fact that the ocean can circulate the heat downwards through turbulence, while there is no such circulation in the land … but still people claim the ocean can’t heat from DLR but the land can. Logical contradiction, no cookies.
Argument 2. If the DLR isn’t heating the water, where is it going? It can’t be heating the air, because the atmosphere has far too little thermal mass. If DLR were heating the air we’d all be on fire.
Nor can it be going to evaporation as many claim, because the numbers are way too large. Evaporation is known to be on the order of 70 w/m2, while average downwelling longwave radiation is more than four times that amount … and some of the evaporation is surely coming from the heating from the visible light.
So if the DLR is not heating the ocean, and we know that a maximum of less than a quarter of the energy of the DLR might be going into evaporation, and the DLR is not heating the air … then where is it going?
Rumor has it that energy can’t be created or destroyed, so where is the energy from the DLR going after it is absorbed by the ocean, and what is it heating?
Argument 3. The claim is often made that warming the top millimetre can’t affect the heat of the bulk ocean. But in addition to the wind-driven turbulence of the topmost layer mixing the DLR energy downwards into lower layers, heating the surface affects the entire upper bulk temperature of the ocean every night when the ocean is overturning. At night the top layer of the ocean naturally overturns, driven by the temperature differences between surface and deeper waters (see the diagrams here). DLR heating of the top mm of the ocean reduces those differences and thus delays the onset of that oceanic overturning by slowing the night-time cooling of the topmost layer, and it also slows the speed of the overturning once it is established. This reduces the heat flow from the body of the upper ocean, and leaves the entire mass warmer than it would have been had the DLR not slowed the overturning.
Argument 4. Without the heating from the DLR, there’s not enough heating to explain the current liquid state of the ocean. The DLR is about two-thirds of the total downwelling radiation (solar plus DLR). Given the known heat losses of the ocean, it would be an ice-cube if it weren’t being warmed by the DLR. We know the radiative losses of the ocean, which depend only on its temperature, and are about 390 w/m2. In addition there are losses of sensible heat (~ 30 w/m2) and evaporative losses (~ 70 w/m2). That’s a total loss of 390 + 30 + 70 = 490 w/m2.
But the average solar input to the surface is only about 170 watts/square metre.
So if the DLR isn’t heating the ocean, with heat gains of only the solar 170 w/m2 and losses of 390 w/m2 … then why isn’t the ocean an ice-cube?
Note that each of these arguments against the idea that DLR can’t warm the ocean stands on its own. None of them depends on any of the others to be valid. So if you still think DLR can’t warm the ocean, you have to refute not one, but all four of those arguments.
Look, folks, there’s lot’s of good, valid scientific objections against the AGW claims, but the idea that DLR can’t heat the ocean is nonsense. Go buy an infrared lamp, put it over a pan of water, and see what happens. It only hurts the general skeptical arguments when people believe and espouse impossible things …
w.
David A
People cannot answer your question because the investigatory experiments have not been carried out. Accordingly, the empirical data does not exist so that quantative figures can be put forward.
richard verney says:
August 21, 2011 at 4:13 am
“Good to see that Konrad has done an experiment. However, I suspect that laboratory conditions are required, before one can draw conclusions”
No Richard, laboratory conditions are not required. While I can achieve those conditions (my new “Dark cool sky “ will be cooled to -50c with a peltier chip), I specifically designed the original experiment to be repeatable by others. I encourage you to attempt it. As to my technical competency, I yell at the screen every time I see the “Mythbusters” try to do controlled experiments. How many years FX experience? Those guys don’t even have movie credits!
RJ says:
August 21, 2011 at 4:06 am
It means for example if say 100 units of energy are in a box. 25 leave and one (8% times 50%) return (after hitting CO2. 92% pass straight though but 8% do not)
Somehow this returning 1 unit of energy (LWR) replaces not only the energy from the other 24 units but also quite a bit more. It is total and utter nonsense.
You have the analogy wrong. If your understanding is flawed, it is no wonder you think the theory is flawed. The one key detail you left out of your analogy is the sun! The sun in your analogy would be providing 25 units of energy each second to the “box” (which clearly represents some section of the earth’s surface
CASE 1: No GHG. Every second the “box” gets, say, 25 units of energy from the sun. The “box” adjusts its temperature until it looses 25 units of energy via IR radiation.
CASE 1: With GHG. If I now add a layer of CO2, then two units of energy that leave the box get adsorbed by the CO2. Assuming CO2 is also at its equilibrium, it has also adjusted its net energy flow to be zero. It will radiate one unit to the ground and one unit to space.
The one returning unit up energy PLUS THE 25 NEW UNITS FROM THE SUN, result in the “box” having one extra unit = more thermal energy = higher temperature. Eventually the box (and atmosphere) will equilibrate at some new, higher temperature.
Of course, this is a gross over-simplification. To get closer to the real world, we need multiple layers of CO2. And water vapor. And clouds. And evaporation. But that does not change the basic principle governing thermal equilibrium or IR radiation to/from the atmosphere.
Sorry, but you are making the same fundamental mistake that WIllis is, you are attributing the properties of your inflow to your outflow. The only way to increase temperature (or in your analogy, to increase the water level) is to add heat (or add water). slowing the loss of heat (or the loss of water) does not do that. You can see this in your water level analogy by doing a simple experiment – fill a swimming pool that has a leak in it. plug the leak and then turn off the hose that was filling the pool, does the water leave rise after you plug the leak and turn off the hose? no not at all, because plugging the leak (slowing the loss of water) does not add a single drop of water to the pool – only the inflow of water from the hose does that. So “slowing the cooling” is not the same thing as warming because only one of those two things is the actual cause of increasing temperature
Konrad says:
August 20, 2011 at 6:05 pm
I like your simple experiment, you appear to have proved the “Greenhouse” effect just like a greenhouse when no evaporation takes place.
But in the real world it has little effect because a lot of evaporation does take place.
Of course it is far too simple for scientists as it doesn’t involve expensive machines and computer models.
To say nothing of Convection as well, which is what the evaporation turns in to.
Tim Folkerts says:
August 21, 2011 at 5:53 am
RJ says:
August 21, 2011 at 4:06 am
The one key detail you left out of your analogy is the sun!
You seem to have frogotten that the sun does not shine on the same surface 24 hours per day. so half the time RJ is correct.
Konrad says:
August 21, 2011 at 5:47 am
Did you run your experiment at night time?
Let’s work with this “potential difference” idea.
The sun is at a vastly higher “thermal potential” than the earth. There is a huge flow of thermal energy from the sun to the earth. The amount of energy flow is determined not only by this “thermal potential difference”, but also by the properties of the earth (albedo) and the geometry of he situation (if the earth were closer to the sun, the sun would appear larger in the sky and we would get more energy, and the earth is a sphere).
(This is just like the idea that the energy delivered by an electric potential difference depends of the geometry of resistor and why it is made of.)
Adding in the albedo reduces this to about 235 W/m^2
Space is at a vastly lower “thermal potential” than the earth. And space is visible in basically every direction EXCEPT where the sun is. If there was nothing else in the way, the equation would read.
Of course, the earth would be cooling dramatically if that were the case. Without GHGs and clouds, we would have to use 3 K as the temperature of the “cold side”, not the temperature of the atmosphere, since the atmosphere would not be involved in radiating.
Fortunately we, have SOME of this “leak” plugged by the atmosphere.
Jonathan T Jones says:
August 21, 2011 at 6:27 am
But “turning off the hose” = “shutting off the sun” !
The better analogy is something like this …
A swimming pool (assume it is above ground) has a crack along one side. The deeper the water, the faster it will leak. If you keep pumping water into the pool, the water level will settle at some depth — lets say 3 ft deep.
Now we create a rather bizarre solution to our problem. We build a small pool onto the side of the original pool WITH THE SAME CRACK in it. The water has to leak from the original pool thru the small pool and then out onto the ground.
Since the small pool as the same crack, it will fill to a height of 3 ft to maintain a leak rate equal to the rate the hose is filling the original pool.
BUT the original pool has to be ABOVE 3 ft deep to leak into the second pool! If the original pool an the second pool were both at 3 ft. there would be no pressure driving the water from one to the other (no “potential difference” as others have called it.
The second pool added NO WATER the the first, but it did result in the 1st pool being deeper than in had been, because at least for a while it slowed the flow out of the first pool !
(it is still not a perfect analogy by any means. I can think of several improvements of the top of my head. But now it illustrates the ability of the intermediate atmosphere to help raise the temperature of the surface without the atmosphere having to “create” any energy. The atmosphere simply slows the escape of the energy, resulting in a higher temperature of the surface.)
Willis
Please just answer this one simple question.
If DLR is ‘real’ as you allege (and not something which in effect is just a signal not capable of performing sensible work in the energy system we experience here on Earth, as I allege), please advise why DLR meters/pyrgeometers are not scaled up (on an industrial scale) and used to produce energy/electricity (or similar) to power something useful for mankind and/or otherwise supplement his energy needs.
After all, if they are measuring power, this power could be exploited. Especially given that there are many places on Earth which are rather cloudy (such as the UK and Northern Europe which places would greatly benefit from being able to tap into the warm clouds which according to you supply so much DLR) and which places would benefit from a 24/7 energy source available come rain, cloud or shine.
I look forward to seeing your answer to this straight forward and simple question.
richard verney says:
August 21, 2011 at 4:13 am
Willis has gone very quiet recently, which is disappointing given that he raised this debate. It is likely that Willis is a little out of his depth. This is quite understandable given the lack of empirical data and experimentation carried out on the issues involved.
Richard, those of us who like yourself have put some intensive thought into this fundamentally important issue find it disheartening that fellow sceptics with strong voices like Willis have swallowed the AGW proponents arguments on this issue. It’s clear to me, you, Tim the Tool man, Dave Springer and many others that they have it badly wrong.
Where does ‘back radiation comne from? Well, it was first emitted by the ocean, thereby cooling it. Then something less than half of it gets bounced back down again, along with ‘new’ longwave derived from the absorption of solar shortwave in the atmosphere. Yet instead of differentiating between these quantities, the pro AGW camp just lump it all together and claim it ‘warms’ the ocean by direct absorption. – Just insane IMO.
Well, it certainly has been a long and contentious discussion with lots of interesting positions. It seems that most are over confident, that the whole process of photon annihilation is quite well explained and understood. This confidence seems to also extend to the surface tension layer of water as well.
I recall the same identical arguments taking place in a room 40yrs ago in a room full of physicists, chemists, and engineers trying to achieve a heat balance account of a nuclear pile. Nothing much has changed since.
The nano-surface of water is not ordinary water at all. Some will claim it is not ordinary space either. Chemistry and even convection, evaporation, exhibits unusual behavior. Even photon conversion to electron flow, within a solar cell creates heated debate. Is it a void migration or a particle flow?
Take a high energy photon, pass it near certain nucleonic field, and some photons, no longer want to be a discrete packet and split into a positron/electron pair, which depart from each other at specified entangled angles (pair production effect). Matter from light. Indeed E=MC2 quantifies the effect, but does not explain it.
To think all these issues will be resolved within a blog discussion is a little beyond, a reasonable expectation. Quantification is the best we can expect at the moment. Experimental data is the only way, for now. So discuss all you want, but do not scoff at each other’s hypothesis, because none of you are completely correct. IMHO GK
Tallbloke, what did you think of Konrad’s simple experiment, it appears to show that both camps are correct to a degree (no pun intended).
There is a slight Greenhouse effect, but it disappears when evaporation/convection occurs.
richard verney says: August 21, 2011 at 8:04 am
Willis
Please just answer this one simple question.
If DLR is ‘real’ as you allege (and not something which in effect is just a signal not capable of performing sensible work in the energy system we experience here on Earth, as I allege), please advise why DLR meters/pyrgeometers are not scaled up (on an industrial scale) and used to produce energy/electricity (or similar) to power something useful for mankind and/or otherwise supplement his energy needs.
This ‘experiment’ has effectively already been done using concentrating solar cookers – which show that the DLR claimed to have TWICE the power of the Sun when concentrated causes COOLING. On the bright side, mankind can benefit from using concentrated DLR as a refrigerator for the 3rd world. If you actually want to heat something, you have to use the Sun (even though according to AGWers “backradiation” has twice the heating power).
http://solarcooking.org/research/McGuire-Jones.mht
http://chriscolose.wordpress.com/2010/05/08/stoat-taking-science-by-the-throat-latest-posts-archives-about-rss-contact-profile-me-my-family-and-me-more-make-sure-youre-familiar-with-the-comment-polic/#comment-2363
http://hockeyschtick.blogspot.com/2010/06/why-conventional-greenhouse-theory.html
tallbloke says:
August 21, 2011 at 8:29 am
Where does ‘back radiation comne from? Well, it was first emitted by the ocean, thereby cooling it.
This is a very good point. Much if the DLR from the clouds is heat that was removed from the oceans. You have to be very careful when calculating any budget (energy or otherwise) to avoid double counting the same item (energy) twice and creating a false picture.
We see this problem all the time in financial accounting. It is one of the great strengths of double entry accounting is that high-lights double postings that would otherwise be hidden by single entry accounting.
The energy budget created by climate science is single entry accounting and subject to undetected double posting errors. If anything, Trenberth’s “missing heat” reminds me of a single entry financial system that is “out of balance”. Something has been overlooked or double posted, creating missing energy.
Hockey Schtick says:
August 21, 2011 at 9:11 am
The Solar Cooker tests were fascinating, particularly the night time ones. An absolute proof that down welling IR does no heating work.
I conducted some similar daytime tests about 10 years ago in the UK using a Torch 4″ parabolic Reflector. A piece of 1/2″ diameter steel placed at the bulb’s Focal point reached 350 degrees C after a few minutes when the sun was focused on that point. We wanted to repeat the tests using the Reflector from a 12″ Searchlight but were unable to obtain one at a reasonable price.
The overall intention was to run a Copper Pipe loop with water through the focal point to see how much water we could heat up. But we were distracted by other things.
G. Karst says:
Experimental data is the only way, for now. So discuss all you want, but do not scoff at each other’s hypothesis, because none of you are completely correct.
The history of science shows this time and time again. “Why” something happens is never settled in science. As new understanding arises, new theories about “why” something happens will always emerge. This is the great fallacy of science, that by understanding “why” we will somehow be able to predict. Much of the current problem in science is a result of this mistaken belief.
What science teaches us is the art of prediction, without requiring an answer to “why”. A dog chasing a rabbit will never catch the rabbit if it aims for the rabbit. By the time the dog arrives the rabbit will have moved. To be successful the dog must predict where the rabbit will run, and arrive there at the same time.
This is the essence of science. To predict where the rabbit will run. “Why” the rabbit is running is not an interesting question. Maybe the rabbit is running to get away from the dog, or maybe it just likes to run in random patterns. It doesn’t affect our ability to predict.
What matters in science is the ability to predict where the rabbit will run, not why the rabbit is running. As we learn in English. Who, What, When, Where – these are adverbs – they modify action . “Why” does not belong, it isn’t science, it is philosophy.
ferd berple says: August 21, 2011 at 9:50 am
You have to be very careful when calculating any budget (energy or otherwise) to avoid double counting the same item (energy) twice and creating a false picture.
Exactly – and here’s why the AGWers go wrong on the accounting – they assume massive heat transfer is occurring from cold to hot and vice versa, failing to consider that if a cold body could (in violation of the 2nd law) cause any heating of a hot body, the hot body would simply emit this additional heat to compensate. In their single entry accounting system they only assume the former, not the latter.
The proper form of the equation for heat transfer shown in the physics literature acts as a dual entry accounting system to eliminate this error. The AGWers fail to understand this.
http://wattsupwiththat.com/2011/08/15/radiating-the-ocean/#comment-724144
A. C. Osborn says:
August 21, 2011 at 6:58 am
You seem to have frogotten that the sun does not shine on the same surface 24 hours per day. so half the time RJ is correct.
My goodness! If this is what you are worried about, let me change the analogy … “The hose runs for 10 minutes, then is shut off for 10 minutes, continuing this cycle indefinitely”. The pool will fill slightly during the 10 minutes the hose is on, an empty slightly during the 10 minutes the hose is off.
This changes absolutely NOTHING about the analogy. Basically you are pointing that the earth cools at night and warms during the day. The atmosphere is STILL acting as a buffer between earth and the 3 K temperature of outer space. The earth is warmer day and night than it would be without that buffer.
“Hockey Schtick says:
August 21, 2011 at 9:11 am
The Solar Cooker tests were fascinating, particularly the night time ones. An absolute proof that down welling IR does no heating work.”
The simple fact that you cannot focus the DLR to reduce the rate of cooling of the surface is fairly strong observational evidence that DLR is not affecting the cooling rate.
Otherwise, we could all place large reflectors outside our houses to reduce the rate of cooling at night. We know for example, that glass (greenhouse) reflects IR. So in theory we should be able to construct heat engines by reflecting the DLR to the hot side of the engine, shading the cools side from the DLR.
So, for example, if you placed two trays of water outside at night, one with a sheet of glass reflecting the DLR onto the other, then the tray with the reflected DLR should cool much slower than the tray shielded from the DLR.
Give this a try and report back to us. Don’t place the glass so close to either tray that if affects evaporation, simply place it so that it intercepts the DLR reaching one tray and concentrates it on the other.
I’m pretty sure that there will be no difference between the two trays, otherwise someone would have used this very simple method to optimize net heating and cooling at night. Given the price of energy and the vast amount of DLR as compared to solar energy, the economics are too great for this to have been overlooked.
Fred Berple says :
Much if the DLR from the clouds is heat that was removed from the oceans. You have to be very careful when calculating any budget (energy or otherwise) to avoid double counting the same item (energy) twice and creating a false picture.
I think you (and many others) need to rethink your paradigm. I challenge you to think about what happens between today and tomorrow.
The earth and atmosphere ALREADY have a great deal of thermal energy. They have had billions of years to get to where they are now, so the original source of that energy is not important. What IS important is what happens from here forward. What IS important is the energy balance of each part of the system.
During the next 24 hr on average, the surface:
* gains ~ 170 W/m^2 via photons from the sun
* gains ~ 320 W/m^2 via photons from the atmosphere.
* loses ~ 80 W/m^2 via evaporation
* loses ~ 20 W/m^2 via convection
* loses ~ 390 W/m^2 via photons (some of which end up in the atmosphere, and some of which end up in space.)
NET CHANGE = ~ 0 W/m^2
energy is conserved; nothing is double counted.
During the next 24 hr on average, the atmosphere:
* gains ~ 70 W/m^2 via photons from the sun
* gains ~ 350 W/m^2 via photons from the surface.
* gains~ 80 W/m^2 via evaporation
* gains~ 20 W/m^2 via convection
* loses ~ 520 W/m^2 via photons (some of which end up in the surface, and fewer of which end up in space.)
NET CHANGE = ~ 0 W/m^2
energy is conserved; nothing is double counted.
The atmosphere is not “returning energy that belongs to the surface”. The atmosphere is “giving out some of it’s own energy”.
Hockey Schtick says:
August 21, 2011 at 10:57 am
The proper form of the equation for heat transfer shown in the physics literature acts as a dual entry accounting system to eliminate this error. The AGWers fail to understand this.
EVEN USING YOUR “PROPER EQUATION”
WITHOUT GHGS and clouds, the equation would be
since the earth would be radiating back and forth with space at 3 K.
WITH GHGS and clouds, the equation would be
Your own “proper equations” show that GHGs & clouds reduce energy loss by ~ 320 W/m^2 from the surface. I know that if I reduce the energy loss thru the walls of my home while keeping the input from the furnace the same, my house will be a higher temperature!
(To be a little more accurate, the second equation should actually some combination of the interactions with the atmosphere and with space. The ~ 70 W/m^2 is a weighted average of the interaction with space and the interaction with .)
ferd berple says:
August 21, 2011 at 11:21 am
So, for example, if you placed two trays of water outside at night, one with a sheet of glass reflecting the DLR onto the other, then the tray with the reflected DLR should cool much slower than the tray shielded from the DLR.
Actually, something like that DOES work. Google “night-sky cooling”.
Or more familiarly, the “sheet reflecting DLR” could be a cloud, which is very effective at directing thermal IR down at the ground. Ask yourself then, do things cool more slowly on clear nights without so much DLR, or on cloudy nights.
Or yet again, a car under a carport will often have no dew on the windows when an uncovered car does have dew. Why? The sides of the carport are open, so even a slight breeze will ensure the same temperature air for both cars. The covered car has a “DLR” source above (the roof at ambient temperature). The uncovered car has a DLR source above it at a much cooler temperature.
SUMMARY: Increase the DLR, the objects cool slowly. Decrease the DLR, and the objects cool more quickly.
(PS. the terms “DLR” & “ULR” are potentially misleading. It should be “ILR” (incoming longwave radiation) and OLR (outgoing longwave radiation). For the earth’s surface, LR can only arrive from above heading down. For a container of water, much of the “DLR” would actually be coming from the ground.)
PS Here is a “cool” link to radiative cooling. http://solarcooking.org/plans/funnel.htm
It includes actual construction details and actual data.