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.
Discover more from Watts Up With That?
Subscribe to get the latest posts sent to your email.
Noelene said on August 15, 2011 at 10:01 pm:
Answer 1: Air is moving relative to a liquid-containing surface, evaporation happens, wind chill. It’s the water that’s moving but the cooling is still there, with rushing water getting more cooling than a slow-moving river.
Answer 2: The river will feel cool when you get in it, provided it’s cooler than your body temperature, due to the greater heat transfer rate versus air. Your body loses heat faster in water thus it feels cool. (Note: As I was warned long ago in first aid and swim and assorted science classes, you can get hypothermia in 80°F water, as you’ll be loosing heat, it just takes a long while.)
Answer 2a: When standing in moving water (the water is moving around you) the loss of heat is faster than in still water. In still water the water around you warms up a bit, reducing the temperature difference thus slowing the rate of loss. With moving water you don’t get that, rate of loss is higher, water feels cooler than still water.
Sound good to you?
Willis said:
“the actual skin surface of the ocean is almost always slightly cooler than the water immediately below. This is because the surface is cooled by evaporation, conduction to the atmosphere, and radiation.
As a result, the skin almost always runs a bit cooler than the water underneath it, with the predictable result—the very surface skin water is always radiating, cooling and sinking a mm or so, then warming from the warm waters below, and rising again. The very surface is constantly being replaced by slightly warmer water from underneath in a very thin skin-based circulation layer. In this way the heat of the ocean makes it to the surface to be evaporated away.
With this constant interchange, with water surfacing, radiating, sinking a mm or so, warming, and rising again to the skin of the ocean, the DLR striking the surface has the same effect it has at night. It slows the thermal circulation, this time the thin vertical circulation at the very surface. Again it slows the motion of the bulk heat to the surface to cool. As a result, the bulk ocean is warmer than it would be without the DLR.”
I don’t agree with that interpretation.
The 1mm deep cooler ocean skin acts as a buffer between the effects of incoming DLR on the topmost molecules and the flow of energy coming up out of the bulk ocean and into the skin from upward convection and conduction (originally from solar input).
All the ‘circulating’ is therefore contained within the skin and does not affect the rate of energy flow from the bulk below and nor does it allow energy to move downward into the bulk. It is an entirely separate process from ‘normal’ ocean mixing.
The interface between the skin and the bulk is therefore the point at which the DLR effect reduces to zero. The depth of that interface and the temperature differential across it is dictated by the flow balance between the layers that is required to negate the DLR effect.
More DLR actually increases the speed of the process within the skin to prevent any effect on the flow rate up from the bulk. The process is self limiting because once all the DLR has been used up there is no more acceleration of the process.
Given that evaporation mops up five times as much energy as is required to provoke it the idea that there is any energy left over to go into the ocean bulk must be wrong.
So DLR does not warm the oceans nor cool the oceans. The energy transfer process from those warmed topmost molecules increases up through the atmosphere to space via more upward radiation convection conduction and evaporation in a self cancelling exercise because of the buffering effect within the ocean skin.
The consequence is a miniscule adjustment in the surface air pressure distribution as the atmosphere adapts to the changed rate of upward energy flow.
GHGs slow down energy loss from atmosphere to space but the whole package of available negative response mechanisms (with the phase change from water to vapour as an essential component) then accelerates it again for a zero or near zero net effect. The ocean bulk remains unaffected.
Willis, I’m going to think about it some more but after some thought your steel greenhouse idea is wrong, wrong, wrong. The shell and the surface are at the same temperature in deg K if the difference in radii are small.
BTW we could run this as a lab experiment.
This doesn’t preclude an atmospheric “green house effect” as the effect of infrared absorbing gases is that a layer above the surface will warm and the lapse rate will make the surface warmer as convection occurs.
For those who think the DLR warms water what’s wrong with the incoming short wave to cause the observed surface warming?
Willis Eschenbach says:
August 17, 2011 at 12:53 am
You can call it what you want, warming, or slowing the cooling, I don’t understand the difference.
There’s a useful discussion getting underway between Tim and Willis here and I agree with much of what both of them are saying. A lot of confusion has arisen in the past and in this thread because of the conflation of ‘warming’ and ‘slowing the cooling’. Willis thinks that there is no difference and that it’s fine to use ‘common parlance’, I think there is an important difference for the way we conceive of the greenhouse effect, and that ‘common parlance’ should give way to technical definition where it sows confusion otherwise.
The simplest way I can think of to illustrate the difference is to say that ‘warming’ is done by things which are warmer then the things they are warming, whereas ‘slowing the cooling’ is done by things which are cooler than the things they are insulating. In the case of radiative balance we are talking about the surfaces involved rather than the properties of the underlying bulks. The ocean side of the ocean air interface is mostly warmer than the air side.
Earlier in the discussion, Willis attempted to refute my argument that conduction from the surface downwards isn’t effective by saying:
IR heats the top molecule. It passes some reduced amount of that heat to the molecule below. But what tallbloke forgets is that the top molecule can’t make the second molecule warmer than the top molecule, heat doesn’t flow from cooler to warmer.
Since the second molecule is not as warm as the top molecule, in contradiction to tallbloke’s claim, it doesn’t rise to the top. And the same for the layers further down. The heat is transmitted down and down, but each layer can’t heat the lower layer more than itself, heat won’t flow uphill. So the water, though warming, doesn’t “rise to the top” as claimed.
But now Willis says to Tim:
As you point out, the actual skin surface of the ocean is almost always slightly cooler than the water immediately below. This is because the surface is cooled by evaporation, conduction to the atmosphere, and radiation.
As a result, the skin almost always runs a bit cooler than the water underneath it, with the predictable result—the very surface skin water is always radiating, cooling and sinking a mm or so, then warming from the warm waters below, and rising again.
Clearly the discussion is becoming more sophisticated, which is good, because it’s only when we look at the actual physical processes that it becomes clear that while the ocean does indeed absorb the DLR, it doesn’t do much to ‘warm’ the bulk of the ocean. However it does indeed ‘slow the rate of heat loss’ and this means the bulk of the ocean is warmer than it would otherwise be. However, plugging in the empirically derived numbers makes it clear that it doesn’t make it cool a lot slower, and a small increase in DLR relative to ULR caused by increased Co2 wouldn’t make enough difference to account for late C20th warming.
It’s more likely the increased insolation through (empirically measured) reduced tropical low cloud cover which did that.
“However it does indeed ‘slow the rate of heat loss’ ”
Not so sure of that. See my above post at
Stephen Wilde says:
August 17, 2011 at 1:36 am
“It’s more likely the increased insolation through empirically measured reduced tropical cloud which did that.”
Yes but I’d go further and suggest global cloud cover variations from the shifting of the jets along with all the other air circulation systems which respond both to top down solar variability and bottom up oceanic variability.
Willis’s thermostat effect is correct but needs to be extended globally.
Myrrh @ur momisugly August 17, 2011 at 1:09 am
WRT your comments on:
http://en.wikipedia.org/wiki/Thermal_radiation
Sorry Myrrh, this is what it actually says, and I‘ve added emphasis to the words ‘visible light‘:
You need to go to the original link to access eight embedded links.
Here follows a link to the solar spectrum that falls upon Earth, and which is universally agreed to result in heating of the Earth. You assert a different view. Would you care to draw a vertical line therein that defines each side what does and what does not heat the Earth?
http://en.wikipedia.org/wiki/File:Solar_Spectrum.png
Sorry Willis, but DLR is only half local radiative heat transfer. What matters is ‘DLR-ULR’.
DLR on its own is a measure of IR impedance. If an atmosphere had no greenhouse gases, it would have near zero IR impedance; the optical depth would fall to near zero because there would be no optical scattering [absorption, re-emission by other GHG molecules in local thermodynamic equilibrium – remember there may be no thermalisation of IR energy]. So, you’d need low ground temperature to radiate a given amount of energy to space.
This analogy is quite close to what happens in metals when you alloy them. The difference in the way the solid solution atoms’ d-shell electrons interact with the conduction band causes the electrons to scatter thus increasing path length and resistance/impedance so you need a higher potential difference to pass a given electric current for an alloy than a pure metal.
The reason why clouds have much higher DLR than moist air is because they have very high IR impedance. The droplets have dissolved lots of the local CO2. Water and CO2 band IR energy is strongly absorbed and scattered. Because the absorptivity/emissivity is high [c. 1 compared with c. 0.1 for moist air] you get a lot of localised DLR. Because a higher proportion of the IR energy being emitted by the ground/sea is needed to offset that higher DLR, you lose less heat from the ground until its temperature rises. That’s why at night, the sudden appearance of a cloud causes local warming.
But the DLR doesn’t do any actual work. Less heat is lost from the ground until the sum of radiation and convection from the ground and the conduction in the ground change exponentially to a new local equilibrium.
Here’s another view: you’re on the beach and air temperature is 25°C but because the wind speed is high, lots of heat is lost by convection so the sand is only at say 30°C when without convection it would be c.70°C. So, you put up a wind break, sand temperature rises to 45°C and you get pleasantly warm lying on it.
Because [assuming 0.85 emissivity] radiative heat transfer has increased by 86W/m^2 to give constant convection plus radiation, assuming half that extra IR energy is absorbed/scattered by the atmosphere back to the ground and everyone else has put up windbreaks [imagine the Sahara] DLR will rise by 43W/m^2. But that is just the result of the IR impedance causing higher radiative potential for a given power transfer. There is no new energy input to the ground.
DLR can do no work. DLR is a measure of IR impedance. Assess the problems as coupled convection plus radiation.
Answer to George E Smith. local thermodynamic equilibrium exists everywhere and accepting the exponential transients, most of the time emissivity is approximately equal to absorptivity.
Willis writes : “Oh, please, I’m not “pleading” for anything”
I could count the number of times you asked people to refute your points. It was more than once…but meh. waste of time.
Willis writes : “You agree, for starters, that DLR a) is absorbed by the ocean”
If by “ocean” you mean the top 10um of ocean’s water molecules, then yes. However you follow up with “What I don’t understand why “conduction cannot happen”.” because you want the conduction to be downward into the bulk and it just doesn’t happen. The location where the DLR is absorbed is colder than the underlying water. It would break the laws of thermodynamics for any “heat” to conduct downwards. Not to mention the fact there is no excess here anyway. It is, as I said, the coldest place.
Willis writes : “As a result, the skin almost always runs a bit cooler than the water underneath it, with the predictable result—the very surface skin water is always radiating, cooling and sinking a mm or so, then warming from the warm waters below, and rising again.”
Get thee back to school Willis 😉
In the skin layer, its conduction not convection that transmits energy.
eg From “Cool-skin simulation by a one-column ocean model – Chia-Ying Tu and Ben-Jei Tsuang”
“Molecular transport is the only mechanism for the vertical diffusion of heat and momentum in the cool skin and viscous layer”
Willis writes : “During the day, sunlight striking the ocean is absorbed most at the surface.”
I’m not quite sure what you’re saying here. There is a temperature profile that DSR creates as its absorbed in water. Most is absorbed not far below the surface and progressively less makes it deeper but its over meters not really “at the surface”. Or at least thats probably not how I’d descibe it in the context of this conversation.
Willis continues : “If the DLR is warming the skin itself, that absorbed solar energy can’t be moved as easily to the skin and radiated/evaporated away.”
Using what physics do you claim this? If there is excess energy being imparted from the sun, the warm water will convect toward the surface and produce/increase the “hook”. The SST increases, Stefan-Boltzmann kicks in and the rate of radiation increases. More is lost to space and to evaporation and the balance is maintained.
Moving along to the second argument (its not worth addressing the warming of the land part. I think you’re just being argumentative)
“I would agree except for the “immediately”, it suggests that it is re-radiated. It is not re-radiated in any sense.”
Re-radiated as a term is wishy washy, I agree. But I think you know what I mean, the DLR is radiated back up pretty much at the same rate its radiated down and I’m not saying anything about individual photons and where they came from or anything like that.
Over at the Science of Doom, SoD calculated that there is about 42J/m2 heat capacity in the topmost 10um layer of the ocean. We know from the Minnett experiment that clouds can increase the DLR by around 100W/m2. We also know from the Minnett experiment that the surface temperature (relative to the 5cm below surface temparature) changed by around 0.5C at most and even though I disagree with their reasoning, it does put an upper limit on any possible “DLR heats the skin” effect.
And using those values that upper limit is reached in a little less than 0.25 seconds to potentially “heat” the surface. If you believe thats what happens then you need to explain where this energy goes after 0.25 seconds and you need to do it within the laws of thermodynamics. Hence its not conducted down. Its not radiated down. Its not convected down (unless you want to try to make proper arguments for any of those) and instead it must be radiated upwards.
Anyway moving right along and this post is already way too long.
Willis writes : “You can call it what you want, warming, or slowing the cooling, I don’t understand the difference.”
I will indeed call it “slowing the cooling” because thats what it is. I think its important to actually understand the processes behind the numbers and I know thats how you feel too. You wouldn’t have bothered with your recent posts on thunderstorms if you’d felt their effect was adequately wrapped up in the coarse averages the AGWers use.
As much as I respect and admire you, Willis, I think you’re off base here. No one disputes this: if there was an independently-powered IR heater floating in the air, it would add heat to the water below it. The question is, can water emit heat energy to heat water vapor in the air…then after a time delay, have this energy come back and make the emitting water hotter than it was? You have to be careful not to double-count the energy. If you calculate emission based on a temperature and this temperature already includes the effect of returned energy, then you can’t count it again later…the “when” of emission and reception matters. If I had $100 yesterday and I still have $100 today, at no time can I say I have $200.
Stephen Wilde says:
August 17, 2011 at 2:34 am
“However it does indeed ‘slow the rate of heat loss’ ”
Not so sure of that. See my above post at
Stephen Wilde says:
August 17, 2011 at 1:36 am
Thanks Stephen. I’m ready to meet for an in depth discussion. I’m away 14th – 25th sept.
@Willis,
“And I still haven’t heard you or anyone else explain why the ocean is liquid, what mysterious energy source you claim keeps the ocean from freezing solid”
At the earth’s surface albedo of about 0.13, the average temperature of the surface is only about 4 degreesC below zero. At the ocean’s albedo of 0.06 or 0.07 the average temperature of the surface is at or above freezing. So in the simplest case the oceans would be liquid except at high latitudes.
This is the calculation at an albedo of 0.07
http://tinyurl.com/3qjxrg2
So as a starting point, before adding clouds, GHGs, diurnal variations and other complexities, most of the surface of the oceans is above the freezing point of water. It is a common error in the climate community to use the earths planetary albedo of about 0.3, which includes clouds when assessing what is needed from the greenhouse gas effect. But since the surface albedo is lower and the ocean albedo lower still, you don’t need the GHGs until you have the clouds. Even in snowball earth scenerios, there is thought to be open ocean in the tropics.
You should all have seen Planck’s law that says the energy of a photon is equal to Planck’s constant times the frequency, usually indicated with the Greek letter nu. This can also be stated as Planck’s constant times the speed of light then divided by the wavelength. This formula indicates the heating potential of a single photon.
It should be obvious that a peak-output, green solar photon with a wavelength of 0.5 microns has 30 times the energy of a 15-micron photon emitted by a CO2 molecule. Anyone can look at a solar radiation spectrum and see that most of the energy is in the visible range. (One micron is equal to 1000 NM or nanometers) That is solar heating power.
The Earth, being so far away from the sun does not have to rise to the same temperature as the sun to reach an equilibrium point. It can export all the heat energy it receives from the sun using the less-energetic, infrared, photons characteristic of normal terrestrial temperatures.
tallbloke says:
August 17, 2011 at 2:03 am
“Clearly the discussion is becoming more sophisticated, which is good, because it’s only when we look at the actual physical processes that it becomes clear that while the ocean does indeed absorb the DLR, it doesn’t do much to ‘warm’ the bulk of the ocean. However it does indeed ‘slow the rate of heat loss’ and this means the bulk of the ocean is warmer than it would otherwise be. However, plugging in the empirically derived numbers makes it clear that it doesn’t make it cool a lot slower, and a small increase in DLR relative to ULR caused by increased Co2 wouldn’t make enough difference to account for late C20th warming.”
Indeed, as I said in my post here, David says:
August 15, 2011 at 1:08 pm, I have seen none of this quantified. I lean to the idea that the residence time of SWR entering the oceans is much greater then the residence time of LWR energy entering the oceans, therfore a small change in the radiative balance via SWR flux, due to either the sun and or cloud cover, would, over time, produce a far greater effect on the earths ocean, atmosphere energy budget then a similar flux in DWLR.
Martin Lewitt; I’ve done the same calculation. It completely disproves the IPCC claim that present greenhouse gas warming is 33K. That assumes in an IR transparent atmosphere, the -18°C presently in the upper troposphere would move to the earth’s surface.
However, all it does is to estimate the temperature difference between that part of the atmosphere presently in radiative equilibrium with space, a function of emissivity/pressure, and the Earth’s surface; is effect an estimate of lapse rate [5km for -6.5K/km].
In reality, if you took out the greenhouse gases and clouds, the albedo would fall to the no-ice level of 0.07 and the power input would increase. A better estimate would account for aerosols so I believe current net greenhouse warming is c. 10K.
The fact that the IPCC scales to 33K shows how desperately bad is basic physics in climate science. Yet they’ve all got a good education. Mustn’t be too critical though because the DLR argument means the subject is subtle and it takes very good physics to get to the truth.
PS If DLR was an energy source, my beach windbreak argument would mean we could control the temperature of the planet by cutting all vegetation down and by only building underground thereby maximising convective heat transfer from the ground to the air. Oh, sorry, I’ve just invented the reverse UHI effect, make everywhere no tree rural!
Willis,
The 170w w/m2 and 390 w/m2 are like comparing apples with oranges, they both warm the surface differently and therefore can’t be claimed to be equal energy quantities. This is where you have gone wrong and this is shown by the observed NASA radiation buget. The outgoing radiation buget is lower than claimed by observed compared with the model example represented.
Looking at this at a different way, if the two energy values were equal, then it would be expected that DLWR would warm the surface greater than solar energy. Care to show any real life observation where this shows to be true and is reflected generally all over the planet. Real life observations show when the sun is warming during the day the result are the hottest temperatures possible in this air mass. When it clouds over and DLWR increases the atmospheric temperatures drop during daylight. This would not occur if the claimed energy values were comparing apples with apples. I think you need to consider this and reanalyse a mechanism that doesn’t make sense.
Alexander Duranko says:
August 17, 2011 at 5:14 am
In reality, if you took out the greenhouse gases and clouds, the albedo would fall to the no-ice level of 0.07 and the power input would increase. A better estimate would account for aerosols so I believe current net greenhouse warming is c. 10K.
There seem to be a number of people heading to this conclusion at the moment. One being astrophysicist Joseph Postma:
http://www.tech-know.eu/uploads/The_Model_Atmosphere.pdf
http://judithcurry.com/2011/08/16/postma-on-the-greenhouse-effect/
It looks like he’s right that smearing the insolation instantaneously over the day and night side of the globe using the S-B equation is incorrect, unphysical, and leads to a bad result. I’m not sure all his paper is correct, but I agree with him on this bit.
One comment on the Curry blog is ‘Gradually the lapse rate should almost vanish in absence of all IR absorption and emission’
This serious lack of basic physics’ knowledge** permeates climate science. I’m not a physicist so I have to check thoroughly. Many do not check so it seems they have been badly educated, or perhaps programmed.
**The Wikipedia article on lapse rate is quite good: http://en.wikipedia.org/wiki/Lapse_rate
Alexander Duranko says:
But the DLR doesn’t do any actual work.
Exactly. This is why I have pointed out a number of times that there are no commerical products that use this “heat producing” phenomena.
mkelly says:
August 17, 2011 at 6:16 am
Alexander Duranko says:
But the DLR doesn’t do any actual work.
Exactly. This is why I have pointed out a number of times that there are no commerical products that use this “heat producing” phenomena.
Because it makes no sense to consider DLR separately from the ULR and the sideways LR within the LR flux.
You getting the message yet Willis?
mkelly: the problem with DLR is that it was predicted by Milne in 1922 from a mathematical mistake so when the poor climate experimentalists measured it with their pyrgeometers, not having good enough physics, they thought is was real.
At the same time Hansen had worked out the amplification of TSI rise at the end of an ice age and concluded it had to be CO2, when there was another possible explanation, reduction of cloud albedo.
35 years’ later, climate science central is still flogging high feedback CO2-AGW and claiming the recent plateau in temperature is because the Chinese have been burning more coal and there’s a magical increase of heat to the ocean deeps. It’s bunkum because DLR isn’t an energy source, simply a signal set by temperature, in turn a function of heat flux, and emissivity.
Lindzen says the IPCC predicts between 2 and 5 times the warming, assuming that came all from CO2-AGW, then uses just enough aerosol cooling, different for every model, so they can calibrate by hind-casting. Kiehl has honestly agreed there’s no proof of any CO2-AGW beyond this uncertainty but hopes that as [CO2] rises, aerosol cooling the same, in time it’ll appear.
We’re dealing with a religious movement, not science. The way to defeat it is to remove all the axioms, one by one. There is no DSL Cloud albedo effect cooling is really heating. That physics’ change means that you have the mechanism explaining the end of an ice age. 33K claimed greenhouse heating is really lapse rate and real greenhouse warming is c. 10K.
The carbon traders are having a last ditch attempt to get their way; Cameron writing to support Gillard, Gore-bull’s day of climate action, but it won’t work. In reality, we face significant global cooling because [1] we’ve just been through a solar grand maximum at one point the highest for 11,000 years and [2] CO2-AGW will be a maximum of 0.2-0.3K by the end of this Century
Ken Coffman says:
August 17, 2011 at 4:12 am
If I had $100 yesterday and I still have $100 today, at no time can I say I have $200.
See the back radiation oven for a demonstration.
OK, so it seems as if you agree that DLR does cause the ocean to be warmer than it would otherwise be without any DLR. I’m not sure if Dave Springer agrees with you or not.
This is probably the direction that the debate should go.
tallbloke, I have a question for you.
Many have argued that DLR is absorbed within the first few micrometers of the ocean surface which causes evaporation which cools the surface. This has been offered as the reason that DLR can’t materially slow the cooling of the ocean.
However, in the absence of any DLR, the ocean would still evaporate. What would cause this evaporation? In the absence of DLR the evaporation process would extract heat from the air just above the ocean-air boundary and would extract heat from the water just below the ocean-air boundary. In the absence of DLR the evaporation process would therefore be extracting more heat from the water than otherwise gets extracted by a DLR fueled evaporation process.
So it seems as if, in the absence of DLR, it’s possible for the ocean to cool materially more quickly than it otherwise does (with DLR fueling the evaporation process instead of ocean heat).
Willis,
I note that once again you do not answer my question as to why the ocean at the same latitude (62 degN) freezes at one longitude (19 deg 04 42 E) but not at another longitude (8 deg 45E). Is this because you do not have an answer that fits in with a simple radiative budget?
You quite incorrectly suggest that I have not explained why the oceans do not freeze. I have. The answer lies in the tropics. THE TROPICS IS THE POWER HOUSE OF OUR CLIMATE SYSTEM and understanding what goes on in the tropics is the key to understanding earth’s climate. Fundamental to this, is understanding the ocean in the tropics and the water cycle that takes place there.
You fall into error for a number of reasons such as:
First, you consider only the energy received per square metre. However, what is important is the energy received per metre cube of ocean and this is where the difference in penetrative absorption between solar energy/radiation and DWLWIR is important and comes into play. Solar energy penetrates well to a depth of 1o meteres and heats the ocean to this depth (obviously more heat is absorbed in the first 10s of centimetres and gradually less and less down to 10 metres and relatively trivial amounts below 10 metres). Solar energy can heat a metre cube, in fact it can effectively heat tripple that. This is of utmost importance because it is this volume of water which is being turned over and it is from this volume of water that heat gets transported down into the lower depths of the ocean thereby warming the lower ocean. In constrast, the DWLWIR, at most, is absorbed in the first few microns and boils this off. The energy from the DWLWIR is lost in the evaporation and resulting phase change such that it does not heat the ocean (witness that the very top few micron layer is slightly cooler than the layer below becayse the very top layer has had to give up heat when molecules from it evaporate). The important point is that DWLRIR merely increases the rate of evaporation. Since we know that the very top layer of the surface is slightly cooler than the layer below, even if this very top layer into which the DWLWIR can penetrate could be turned over, there is fact no ‘additional’ heat in this top layer to drag down to lower depths so as to heat the lower depths of the ocean. In fact, I doubt that the top few microns of the ocean could be turned over (but I stand to be corrected on that view).
Second, because as another poster pointed out, a watt is not just a watt. The photonic energy of the 5800k 170 w per sqm is a very different beast to the photonioc energy of the ~250K 390 w per sqm DWLWIR. We know this to be the case since we are able to extract useful work form the former but not from the latter. It is because the 390 w per sq m has no sensible energy in the context of the system in which it is engaged and has no ability to do sensible work that Trenberth and the Team are not multi – billionaires having patented a system to extract energy frrom the DWLWIR thereby solving the world energy problem. It is wrong to consider that Solar radiation and DWLWIR are the same and equally effective, they are not. Further, a watt of energy that has penetrated down to a depth of 2m or 4 or 10m is far more significant in the role of heating the deep oceans than is a watt which never makes it past the first few microns (and which in any event is probably boiled off at that stage). That latter watt does not get to heat the deep oceans.
Third, you consider that because the ocean radiates at the temperature of the surface skin, it is losing a lot of energy. In the overall scheme of things (by which I mean in relation to the total energy contained in the entire volume of the ocean), the amount of energy radiated is trivial and it is important to bear in mind that the so called ~390 – 400 w per sqm being seen as a signal is not heat loss. The ocean is not actually losing a lot of energy (in comparison to that contained in its bulk) and the amount of energy that it loses to the atmosphere is less than it receives from the sun. In this regard, do not forget that unlike land where air temperature and land temperature can be very different, over the deep oceans, ocean temperature and air temperature are very similar.
Fourth, you look at the notional average condition whereas in the context of the workings of the system the dominant condition is that ongoing at the TROPICS. It is here that one has to consider what is going on. As BenAW says:August 16, 2011 at 10:55 am “How come everybody is talking about AVERAGE radiation levels resulting in AVERAGE temps using the Stefan-Boltzmann formula when there is a fourth power in this formula? Earth has ONE sun, that radiates on half the earth. Average radiation on this half is 1364/2 = 682 W/m^2 ….” Ben is quite right (as I have repeatedly been saying to you), you will not understand what is going on if you look only at the notional average condition.
Fifth, the material point (and this follows on from the fourth point), is that at the tropics the ocean is not receiving just 170 w per sqm of solar energy. It is receiving many many times that amount. Even the 682 w per sqm noted by Ben is far less than the ocean is receiving in the tropics, particularly during the 4 hour period between 10 am and 2pm when the sun is near to and/or at its zenith. When one works out how much energy the tropical ocean receives from the sun during the day, it is significantly more than the energy being lost to the atmosphere over a 24 hour period through all ongoing processes (convection, evaporation and radiation) such that the tropical ocean will not freeze. Indeed, not simply will it not freeze, it has surplus energy which energy it is able to distribute around the globe (through the ocean conveyor belts) thereby (for the main part) making up the shortfall of energy which the ocean in higher latitudes receives thereby preventing those oceans from freezing.
Sixth, generally radiative energy yields to and does not overcome convection. This can be seen with a BBQ. The heat given off by the burning embers is radiative heat and is given off in all directions. If you were to point your IR thermoter at the BBQ there would be no difference in the IR temperature reading when looking down at the BBQ or when looking at it from its side. You can cook your food 6 to 12 inches above the charcoal/coals but you cannot cook your food 6 to 12 inces from the side of the BBQ. The reason is that notwithstanding that the source of the heat is radiative, the food is cooked by convection. Convection carries the heat (that was initially radiative heat) upwards towards the food placed above the charcoal/coals. If you place the food say 9 to 12 inches to the side of the BBQ, most of the radiative energy radiating sidewards is carried upawrds by convection such that there is all but no heat energy left 9 to 12 inches from the side of the BBQ. The same process is occuring above the ocean. The DWLWIR is trying its best to get down to the ocean surface and penetrate the water, however water vapour above the ocean impedes its path and the DWLWIR is continually being absorbed by that vapour and then that vapour (which has absorbed the DWLWIR) is being absorbed convected upwards and away from the top layer of the ocean. I envisage that less DWLWIR actually makes its way to the surface of the ocean than is presently assumed.
Seventh, the Trenbeth figures are fantasy. Essentialy they are a fiction of robbing Peter to pay Paul. In the real world the bulk of the energy loss from the oceans is not the radiative loss from the instaneous absoption/emission involved in the receipt of the DWLWIR and its re-radatiation, but rather from vaporation and convection. In practice as I and others have repeatedly observed, it is net flux that is important (but I guess that you are never going to be convinced of that although alarm bells should ring if substantially different results are achived by performing a calculation on so called gross figures and one on net flux figures).
In summary, Willis do your Solar/DLR energy budget calculation for the TROPICAL OCEAN. Whilst I would prefer that you base this on net flux, in practice I do not care whether you use your fantasy figures since even if you do use those figures, you will still find that THE TROPICAL OCEAN DOES NOT FREEZE. Come back to me once you have done that calculation.
PS. I do not understand why so much time in climate science is wasted on peripheral issues. Approximately 70% of the planet is covered by ocean. The ocean contains 99% of the heat capacity of the planet, and it is the oceans that drive the weather. Given that, nearly all study should be directed at studying and understanding the oceans and the water cycle. Of the oceans, it is the tropical ocean that powers everything. Accordingly, the one area to thoroughly understand is the tropical ocean and the water cycle. Study of this would force people away from darn averages that do nothing other than to obscure what is going on. The rest of the globe is of mild interest only, and not of fundamental importance (although as I have mentioned in previous posts I can conceive that DWLWIR may have some relatively modest role to play over land). Enough of that particular gripe.
PPS. Since I last looked in on this article there have nbeen many new posts. I need to do some catch up.
wobble says:
August 17, 2011 at 8:02 am
Many have argued that DLR is absorbed within the first few micrometers of the ocean surface which causes evaporation which cools the surface. This has been offered as the reason that DLR can’t materially slow the cooling of the ocean.
No. It’s partly why it can’t directly warm the ocean, along with the inability to conduct heat downwards due to the surface being colder then the subsurface, and the lack of a convective mechanism to do the job, and the fact that the net flux is cooling the ocean anyway.
The reason I provisionally accept the idea that DLR can slow the cooling of the ocean is that if we consider what happens when DLR increases relative to ULR, the net cooling caused by the direction of the 66W/m^2 net flux would be diminished. However, we have yet to see any empirical evidence that the DLR has increased relative to the ULR.
Stephen Wylde seems to be saying that any increasing differential gets automatically compensated for. I’m looking forward to discussing that with him in detail.
DWLWIR isn’t an energy source. I agree about the short wave energy.
The dominant organism in the World is phytoplankton because it emits c. 10 times the aerosols of man. It has over 100s of millions of years adapted to control its environment by the peculiar chemistry producing dimethyl sulphide on decay, and because that has very low water solubility it goes into the air to be photo-hydrolysed to sulphuric acid aerosol.
This is what is responsible for the classic smell of the oceans. Without these aerosols, low level thick oceanic cloud albedo would be much greater and the oceans and the World would cool rapidly. Asian industrialisation added more sulphuric acid aerosols thereby causing the late 20th Century increase in ocean heat content which stopped in 2003.
It stopped because the warming due to polluted clouds runs out of steam when albedo gets near 0.5. When Asia reduces emissions, the effect will reverse and Trenberth’s ‘missing heat’ will become negative!
CO2-AGW could well be net zero.