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.
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@tallbloke
The paragraph from the Geophysical Research Paper (actual experimental science not toy computer model output) is a summary of many individual times and locations. There’s a wealth of information in it. Enough budget tables of individual times and places to make your head spin. Inputs and outputs don’t balance in instant cases. For instance the authors measure how much summertime heating of the mixed layer is entrained until winter when the balance goes the other way which of course it must do and is why there’s little seasonal temperature variation compared to land. Where the energy goes in and where it comes out also moves around to some degree due to winds and ocean currents and precipitation patterns. At the end of the day (or year rather) it all balances out. Energy into the ocean equals energy out of the ocean equals constant average ocean temperature. The argument for any imbalance caused by AGHGs is in the margins which is why this debate is unending. The take home lesson is how small those margins are the utter dearth of empirical evidence saying they fall on side of more energy input than ouput.
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Dave Springer says:
August 16, 2011 at 4:30 pm
This whole damn article was a response to ME for suggesting in a different article of his that LWIR from greenhouse gases doesn’t effect the ocean to any significant degree. I don’t begrudge him the ability to respond to an obscure comment of mine with a headline, large print, pretty pictures, and words directed at me like silly, nonsense, impossible, and ugly.
There’s a good deal of back history you may not be aware of:
http://tallbloke.wordpress.com/2010/11/16/whatever-happened-to-back-radiation-part-ii/
http://tallbloke.wordpress.com/2011/03/03/tallbloke-back-radiation-oceans-and-energy-exchange/
w.
tallbloke says:
August 16, 2011 at 2:56 pm
Willis Eschenbach says:
August 16, 2011 at 2:41 pm
This means that information has been thrown away to get to the “net flow” number, and I prefer not to throw away information when I don’t have to.
Let’s be super-generous to ourselves and have all the numbers on the table
Downwelling solar absorbed by the ocean ≈ 170 W/m2
Downwelling ‘back radiation’ ≈ 320 W/m^2
Total = 490 W/m^2
#######
I think you’ve all lost the plot.
Downwelling Solar 170 W/m^2 is not heating the Earth. Visible Light, UV and Nr IR are not thermal energies – they cannot be heating the land and oceans to raise the temperature by the amount claimed nor can they therefore create that much Infrared upwelling from the Earth.
You’re in gobbledegook land the lot of you, who are arguing as if this is real.
The ‘missing heat’ is Thermal Infrared direct from the Sun…
Perhaps you can’t hear me because the atmosphere you’re in is empty space, and sound doesn’t travel in empty space..
..now where did I put that popcorn..?
Thanks Matt and Dave – signing off for sleep.
TB
Bob_FJ says:
August 16, 2011 at 4:46 pm
It can become clumsy at times and difficult for the layperson (including me) to follow but ultimately everything in the universe is composed of energy which can be neither created nor destroyed. Matter itself is a form of energy with the equivalence defined by the equation e=mc2. Thus everything can be described in terms of energy flows measured in any arbitrary term you choose – joules, watts, btus, horsepower, whatever. There are equivalancy equations for converting any of them one to another. EMR and heat are both energy. Following it all its forms is a tough row to hoe but at the end of the day that’s what it boils down to – energy flows – and because energy can be neither created nor destroyed if you can balance the energy accounting from start to finish in any process of interest then you probably got it right. If the books don’t balance then you’ve definitely missed something.
tallbloke says:
August 16, 2011 at 4:58 pm
“Dave Springer says:
August 16, 2011 at 4:30 pm
This whole damn article was a response to ME for suggesting in a different article of his that LWIR from greenhouse gases doesn’t effect the ocean to any significant degree. I don’t begrudge him the ability to respond to an obscure comment of mine with a headline, large print, pretty pictures, and words directed at me like silly, nonsense, impossible, and ugly.
There’s a good deal of back history you may not be aware of:
http://tallbloke.wordpress.com/2010/11/16/whatever-happened-to-back-radiation-part-ii/
http://tallbloke.wordpress.com/2011/03/03/tallbloke-back-radiation-oceans-and-energy-exchange/”
Yeah but in this particular case the raiser of the silly, impossible, ugly headed nonsense was me. The nerve that I touched was already exposed but it was still me who touched it this time and set Willis off on a rant. Thus I took those harsh words personally and considered them to be fighting words so I fully intend to kick Willis’ sorry intellectual ass for it.
Truth be told there’s some residual anger in me for the boorish article Willis penned last week with regard to Native Americans. Even Anthony said he wouldn’t have approved it. So I guess the boor in me, which is admittedly legion, is coming out in response. I don’t really mind lowering myself to that level. It’s kind of fun wrestling with pigs if you don’t mind the mud.
This is absurd. Willis’ argument is that if heat is lost when the ocean emits LR – and it is, indisputably – then it must be gained (or not lost) when the ocean receives DLR. If there is some mechanism by which heat in the ocean is transferred to the surface and radiated – and there is, convection – then a decrease in net radiation means (in the absence of other variables) less heat lost, less convection, and less heat sent to the surface. Sorry but it makes no substantive difference whether you call it less cooling or more warming, when either way the effect of DLR is a higher ocean temperature than would otherwise exist.
What is important is the extent to which less heat radiated = more heat conducted and/or converted into evaporation.
Not all electromagnetic energy heats up organic matter. It’s not simply the case of ‘balancing’ energy in/energy out, this claim is specific to heating land and oceans to raise the temperature.
tallbloke says:
August 16, 2011 at 4:28 pm
“Dave Springer says:
August 16, 2011 at 4:14 pm
The net radiative heat loss at the end of the day is 50Wm, conductive heat loss is 20Wm, latent heat loss weighing in at 140Wm. Energy into the ocean 200Wm which exactly balances out.
Dave, where are your figures from please?”
A typo in there, by the way. Conductive heat loss, per the paper, is 10Wm.
Dave Springer, I was one of the commenters that asked you about your statement in the last thread.
Personally, I’m happy this issue was raised, and I’ve learned quite a bit reading through this thread. However, I’m still not sure what I believe. Can you clarify your position for me? I’m really just trying to understand, and I’m not trying to trap you.
It seems as if you agree that downward infrared radiation, such as that being caused by green house gases, does retard the cooling of land surfaces. Is this correct?
If so, then it also seems as if you agree that an increase in CO2 might provide some marginal amount (even if such marginal amount is minuscule and undetectable) of increased downward infrared radiation towards the earth. Is this correct?
If so, then it also It seems as if you agree that such marginal amount of increased downward infrared radiation also exists over the oceans. Is this correct?
If so, then it also seems as if there is disagreement regarding the effect that such increased downward infrared radiation has on the oceans. Is this correct?
If so, then it seems as if you assert that increased downward infrared radiation has any effect on ocean temperatures. Is this correct?
If I’m right about everything so far, then please let me know if you believe that: 1) an increased amount of downward infrared radiation is unable to have any effect at all (including theoretical) on ocean temperatures; or 2) an increased amount of downward infrared radiation could theoretically retard ocean cooling, but due to offsetting mechanisms (such as evaporation) ocean cooling isn’t retarded in any measurable amount.
Again, I’m really trying to understand what your specific claims are.
Matt G says:
August 16, 2011 at 4:53 pm
tallbloke says:
August 16, 2011 at 4:14 pm
Excellent. Actual net surface energy from NASA. A clear picture unsullied by obfuscatory unnecessary opposing flows that cancel out.
I culled it down to global means to make a point:
Average net shortwave radiation at the Earth’s surface: January 1984-1991.
Global mean = 162 W/m2
Average net longwave radiation at the Earth’s surface: January 1984-1991.
Global mean = -48 W/m2
Average net radiation at the Earth’s surface: January 1984-1991.
Global mean = 114 W/m2
So we see here in simple terms that at the surface, which is where we live and why I eschew obfuscatory Top of Atmosphere budget, we have at the end of the day (or rather end of the decade) a net radiative flow of 114 W/m2.
This 114 W/m2 is the amount of energy that doesn’t leave the surface radiatively. Compare this to 48 W/m2 which is the amount of energy that does leave the surface radiatively. LWIR emission only accounts for 48/114 or 42% of all radiative heat loss from the surface, land and ocean combined. For the ocean-only the radiative loss is only 25% (see my previous link to ocean heat budget).
What this means is that the lion’s share of heat loss is not via radiation and that’s especially true over the ocean. Where radiative loss is not a large factor neither can greenhouse gases be a large factor because radiation is only mechanism by which GHGs do their GHG thing.
Given the ocean is 70% of the surface, for the combined total radiative heat loss to reach 42% the land masses must be very much dominated by radiative loss. But over the ocean, not much. It’s mostly about latent heat loss over the ocean.
This is just more in the way of empirical evidence (not toy models or thought experiments with heat lamps and pans of water) that the GHG effect is predominantly a land based phenomenon.
QED
Peace. Out.
Myrrh @ur momisugly August 16, 2011 at 5:02 pm
Sorry Myrrh, but the term “thermal radiation” is sometimes confused and misused. It is really a misnomer for EMR, (electromagnetic radiation) which includes visible light which does indeed heat matter when its photons are absorbed. Try here at Wikipedia:
http://en.wikipedia.org/wiki/Thermal_radiation
Bob_FJ says:
August 16, 2011 at 4:46 pm
I understand that EMR is not heat. It is energy. EMR can heat things that it hits, that’s why we have microwave ovens. Not sure what your point is. You post a quote of mine that doesn’t contain the word “heat” in any form, and claim I don’t understand that EMR is not heat … of course it’s not heat, it’s EMR.
w.
Willis, you can say it as many times as you want and it still is only a half truth.
I get about 275K for the average with the 170 in. Of course, this close averages may hide stuff, but, 275k isn’t frozen. Also of course, I may have screwed up trying stuff I barely understand even with the BB Calculator.
Myrrh says:
August 16, 2011 at 5:02 pm
Visible light and UV can’t warm things they hit? The sun can’t warm the land? Someone’s lost the plot here, but it’s not us all …
w.
Willis,
“This means that information has been thrown away to get to the “net flow” number, and I prefer not to throw away information when I don’t have to.”
Except when you only say 390 you threw away the 324…
Dave Springer says:
August 16, 2011 at 5:23 pm
My apologies, Dave, if you took it personally. I didn’t even note who had raised the subject on the previous thread, nor did I care. I’ve heard the story too many times, so I wanted to address it. It had nothing to do with you personally, and my words were not aimed at you or anyone. They were aimed at the foolishness of not doing the accounting. What goes in in terms of energy must be about equal to the energy that goes out.
Now, anyone who believes that there is not something on the order of 300 w/m2 of DLR warming the ocean needs to explain, if it’s not DLR warming the ocean, what is.
Nobody has done so. Why?
Because the belief is silly. It doesn’t pass the laugh test, much less the smell test. The ocean is known, not thought but known, to be radiating about 400 w/m2. It has to be radiating that much, because of its temperature. Since it’s not cooling or warming much, it must be receiving at least that amount. I say (see the diagram above) that the energy to make it balance comes from the DLR. Nor is that the only reason to think the belief doesn’t accord with what we know, I list three other good reasons above, none of which have been refuted.
So in your understanding, Dave, if it’s not DLR, what is providing that energy to keep the ocean liquid?
w.
Willis Eschenbach, do you admit that you don’t actually know the amount of warming the “DLR” can cause? Isn’t it possible that the amount of warming that it causes is negligible and even unmeasurable?
Bob_FJ says:
August 16, 2011 at 4:46 pm
Tallbloke seems to think this is a good analogy — I think it is a fair to poor analogy. Electrons are not really all that much like photons. Once a photon is created, it travels pretty freely (until it gets in the neighborhood of an atom). There are no competing fields pushing on it as it flies thru space. A photon heading one way will pass right by a photon traveling the other way.
Electrons, on the other hand are pushed and pulled by fields all thru the circuit. Electrons interact and scatter as they pass each other.
A better analogy would be two separate circuits, one sending electrons counterclockwise around one wire while the other circuit sends electrons clockwise around a parallel wire. The “net current” will be one current minus the other, but electrons really would be flowing both directions.
In a few years… Maybe decades when the current regime is old and feeble. Well they are already feeble in certain regards.
The true case of how the “green house” works will be proven…
The simple fact is water retains heat very well. The atmosphere due to it’s limited mass dissipates heat very poorly. This is what creates the magic that scientists are trying to prove exists. You don’t need hocus-pocus.
You do all that in the dawn of astronomy it was proven that the earth was in the center of the solar system… Worked perfectly on paper. But it was in fact non-sense.
Dave Springer says:
August 16, 2011 at 3:53 pm (Edit)
Oh, good, ad hominem attacks. Dave, you still haven’t explained how the ocean can lose 400 w/m2 in radiation, gain 170 w/m2 from the sun, and still stay liquid. My high school is merely an attempt on your part to divert people from asking you, once again, for your explanation. I do know from my high school education that if the ocean is losing some 230 w/m2 it will freeze solid in a short time … so why is it liquid, Dave?
w.
tallbloke says:
August 16, 2011 at 4:14 pm
“NASA have stopped using the K-T energy budget cartoon on their website which shows the separate LW radiation components and replaced it with this one which only shows the net flow:”
http://tallbloke.files.wordpress.com/2010/06/energy-budget-new.jpg
======================================================
Why is the huge 400 percent INCREASE (of three million+) in submarine volcanic and thermal vent activity LEFT OUT OF THEIR EQUATION???It surely would be greater than a miniscule amount of AWG.
Out of sight out of mind,no doubt.
Bob_FJ says:
August 16, 2011 at 4:46 pm
Willis Eschenbach @ur momisugly August 16, 2011 at 2:12 pm
“…As a result I wrote the arguments list above, and tallbloke and the folks who think DLR can’t warm the ocean started answering (although none have explained why, if the DLR isn’t warming the ocean, it hasn’t frozen yet.”
Willis, please try to understand that EMR (electromagnetic radiation), regardless of wavelength and power, is a different form of energy to HEAT. Put another way, the 400 w/m^2 that you visualise as leaving the surface even though measured in the same units is not rate of HEAT loss. Repeat, EMR is not HEAT.
=======================================================
When EMR interacts with a conductor currents are formed and dissipated as heat. So an EM field generated in air would transfer heat to the ocean (which is a conductor).
EMR radiating back out into space will only find resistance, but EMR striking the earth (and the oceans) will generate heat.
Here is the simplest argument I can come up with for the “reality” of ~ 390 W/m^2 upward and ~ 320 W/m^2 downward thermal IR, as opposed to the “reality” of ~ 70 W/m upward thermal IR.
Take a 1 m x 1 m sheet of material with an emissivity of 1. Make it thick enough to have a heat capacity of ~ 700 J/K. Create a vacuum around it to eliminate conduction & convection. Cool the sheet close to 0 K and then set it out horizontally someplace above the ground.
CASE 1) If there are indeed two fluxes of 390 W/m^2 up toward the bottom of the sheet and 320 W/m^s down onto the top of the sheet, then the two surfaces will absorb = 710 J/s and warm at rate of ~ 1 K every second.
CASE 2) If there is only a “net flux” of 70 W/m^2 upward, then the top will receive nothing and the bottom will receive 70 W, and the sheet will warm at ~ 0,1 K every second. This is a 10x slower rate and would be easy to measure.
Is there anyone who seriously thinks the object will warm at a rate of 0.1 K/s rather than 1 K/s ???