Note: two events at AGU13 this morning dovetail in with this essay. The first, a slide from Dr. Judith Lean which says: “There are no operational forecasts of global climate change”.
The second was a tweet by Dr. Gavin Schmidt, attending Lenny Smith’s lecture (which I couldn’t due to needing to file a radio news report from the AGU press room) that said:
Smith: usefulness of climate models for mitigation 'as good as it gets', usefulness for adaptation? Not so much #AGU13
— Gavin Schmidt (@ClimateOfGavin) December 10, 2013
With those events in mind, this essay from Dr. William Gray (of hurricane forecasting fame) is prescient.
Guest essay by Dr. William M. Gray
My 60-year experience in meteorology has led me to develop a profound disrespect for the philosophy and science behind numerical climate modeling. The simulations that have been directed at determining the influence of a doubling of CO2 on Earth’s temperature have been made with flawed and oversimplified internal physical assumptions. These modeling scenarios have shown a near uniformity in CO2 doubling causing a warming of 2-5oC (4-9oF). There is no physical way, however, that an atmospheric doubling of the very small amount of background CO2 gas would ever be able to bring about such large global temperature increases.
It is no surprise that the global temperature in recent decades has not been rising as the climate models have predicted. Reliable long-range climate modeling is not possible and may never be possible. It is in our nation’s best interest that this mode of prophecy be exposed for its inherent futility. Belief in these climate model predictions has had a profound deleterious influence on our country’s (and foreign) governmental policies on the environment and energy.
The still-strong—but false—belief that skillful long-range climate prediction is possible is thus a dangerous idea. The results of the climate models have helped foster the current political clamor for greatly reducing fossil fuel use even though electricity generation costs from wind and solar are typically three to five times higher than generation from fossil fuels. The excuse for this clamor for renewable energy is to a large extent the strongly expressed views of the five Intergovernmental Panel on Climate Change (IPCC) reports, which are based on the large (and unrealistic) catastrophic global warming projections from climate models.
The pervasive influence of these IPCC reports (from 1990 to 2013) derives from the near-universal lack of climate knowledge among the general population. Overly biased and sensational media reports have been able to brainwash a high percentage of the public. A very similar lack of sophisticated climate knowledge exists among our top government officials, environmentalists, and most of the world’s prestigious scientists. Holding a high government position or having excelled in a non-climate scientific specialty does not automatically confer a superior understanding of climate.
Lack of climate understanding, however, has not prevented our government leaders and others from using the public’s fear of detrimental climate change as a political or social tool to further some of their other desired goals. Climate modeling output lends an air of authority that is not warranted by the unrealistic model input physics and the overly simplified and inadequate numerical techniques. (Model grids cannot resolve cumulus convective elements, for example.) It is impossible for climate models to predict the globe’s future climate for at least three basic reasons.
One, decadal and century-scale deep-ocean circulation changes (likely related to long time-scale ocean salinity variations), such as the global Meridional Overturning Circulation (MOC) and Atlantic Thermohaline Circulation (THC), are very difficult to measure and are not yet well-enough understood to be included realistically in the climate models. The last century-and-a-half global warming of ~0.6oC appears to be a result of the general slowdown of the oceans’ MOC over this period. The number of multidecadal up-and-down global mean temperature changes appears also to have been driven by the multidecadal MOC. Models do not yet incorporate this fundamental physical component.
Two, the very large climate modeling overestimates of global warming are primarily a result of the assumed positive water-vapor feedback processes (about 2oC extra global warming with a CO2 doubling in most models). Models assume any upper tropospheric warming also brings about upper tropospheric water-vapor increase as well, because they assume atmospheric relative humidity (RH) remains quasi-constant. But measurements and theoretical considerations of deep cumulonimbus (Cb) convective clouds indicate any increase of CO2 and its associated increase in global rainfall would lead to a reduction of upper tropospheric RH and a consequent enhancement (not curtailment) of Outgoing Longwave Radiation (OLR) to space.
The water-vapor feedback loop, in reality, is weakly negative, not strongly positive as nearly all the model CO2 doubling simulations indicate. The climate models are not able to resolve or correctly parameterize the fundamentally important climate forcing influences of the deep penetrating cumulonimbus (Cb) convection elements. This is a fundamental deficiency.
Three, the CO2 global warming question has so far been treated from a “radiation only” perspective. Disregarding water-vapor feedback changes, it has been assumed a doubling of CO2 will cause a blockage of Outgoing Long-wave Radiation (OLR) of 3.7 Wm-2. To compensate for this blockage without feedback, it has been assumed an enhanced global warming of about 1oC would be required for counterbalance. But global energy budget considerations indicate only about half (0.5oC, not 1oC) of the 3.7 Wm-2 OLR blockage of CO2 should be expected to be expended for temperature compensation. The other half of the compensation for the 3.7 Wm-2 OLR blockage will come from the extra energy that must be utilized for surface evaporation (~1.85 Wm-2) to sustain the needed increase of the global hydrologic cycle by about 2 percent.
Earth experiences a unique climate because of its 70 percent water surface and its continuously functioning hydrologic cycle. The stronger the globe’s hydrologic cycle, the greater the globe’s cooling potential. All the global energy used for surface evaporation and tropospheric condensation warming is lost to space through OLR flux.
Thus, with zero water-vapor feedback we should expect a doubling of CO2 to cause no more than about 0.5oC (not 1oC) of global warming and the rest of the compensation to come from enhanced surface evaporation, atmospheric condensation warming, and enhanced OLR to space. If there is a small negative water-vapor feedback of only -0.1 to -0.3oC (as I believe to be the case), then a doubling of CO2 should be expected to cause a global warming of no more than about 0.2-0.4oC. Such a small temperature change should be of little societal concern during the remainder of this century.
It is the height of foolishness for the United States or any foreign government to base any energy or environmental policy decisions on the results of long-range numerical climate model predictions, or of the recommendations emanating from the biased, politically driven reports of the IPCC.
###
William M. Gray, Ph.D. (gray@atmos.colostate.edu) is professor emeritus of atmospheric science at Colorado State University and head of the Tropical Meteorology Project at CSU’s Department of Atmospheric Sciences.
John Finn
The surface energy flux is ~500 w/m2, not ~390 w/m2.
“Deterministic” climate???
How that??
What a fool claims that?
Climate is a nonlinear system of higher order.
A stochastic behavior is very usual for nonlinear system of high order.
It is rather an exception when a highly nonlinear system behaves deterministically.
Speaking of climate prediction, do the climate models take into account the slowing of the jet stream when solar cycle diminishes? There has been precious little said on this subject when in fact the jet stream greatly affects the weather bringing unanticipated heat waves, cold snaps, droughts, and pushes/stirs hurricanes. What is the effect of a slowing jet stream on North America’s climate?
Terry Oldberg says:
December 10, 2013 at 7:08 pm
Anthony:
“You mischaracterize a “fallacious argument” as a “semantic issue.” Hopefully, your editorial policy does not favor fallacious arguments. Please clarify.”
You are not going to find a lot of support here for an argument that can be characterized as “semantics.” For the vast majority of scientists and engineers, if you raise a semantic point then their eyes glaze over. So, pick your battles carefully.
As for those who wonder why semantics matters at all, the answer is that the predicate “…is true” is a semantic predicate. The idea of truth can be explained and explicated only through semantics. The authority on that is the late W. V. Quine. You can give up semantics as long as you are willing to give up all claims to truth including the claim that the moon orbits the earth and the claim that our current understanding of radiative physics is true. Hey, others have done it. For example, President Obama is very proud of having become what he calls a “pragmatist.” Now, Obama talks about only “what works” versus “what doesn’t work.”
Finally, when you give up talking about truth you also give up talking about prediction.
@ur momisugly Wrecktafire — glad you enjoyed that. Yeah, the article wasn’t the best part of that post. I hope you can find out an answer to your Q. J
This would be a good time for guidance from Dr. Gray on the seasonal winter forecast recently issued by the Feds that indicated mild conditions this winter for a large swath of the country. That prediction was much different from recent private sector forecasting for commodity futures market research. Since then it has been bitter cold in a good section of the “mild” areas indicated by said Federal agencies. While a cold spell itself does not determine the seasonal outcome, it is worth watching in the case of Federal agencies that simultaneously post global warming information sections and policy positions on their official web portals. The question of impropriety and professionalism is not limited to the UK MET office on this topic.
Scott Wilmot Bennett says:
December 11, 2013 at 6:37 am
TB says:
December 11, 2013 at 3:27 am
AND by way of reply to fredburple
“This wrong in so many ways, I don’t know what to point out first!
1. The Earth is not in equilibrium, it does not have ‘A Climate’ in the sense you use it: “Moreover, it hardly needs stating that the Earth does not have just one temperature. It is not in global thermodynamic equilibrium – neither within itself nor with its surroundings.
It is not even approximately so for the climatological questions asked of the temperature
field. Even when viewed from space at such a distance that the Earth appears as a point
source, the radiation from it deviates from a black body distribution and so has no one
temperature [6]. There is also no unique “temperature at the top of the atmosphere”. The
temperature field of the Earth as a whole is not thermodynamically representable by a single
temperature.”
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Scott:
The Earth is not in equilibrium – at the moment, which is why sea/air temps are rising. However , as it lies in the vacuum of space as an ultimate sink for the Solar energy it receives, basic physics says it should be – by radiative balance. It (in normal conditions) necessarily is in equilibrium with its surroundings (space at 3K). Put a rotating object in a vacuum and heat it with an IR lamp. Comes a point when the object gets no hotter as the S-B law ensures a certain temperature it must reach such that radiation received = radiation emitted. Simple as that. The climate is ultimately governed by that equation. The balance point of energy and the average temp of the planet it causes. Weather happens because of this temperature, topography, spin, the presence of water. Ice sheets etc form to alter albedo feeding back into weather until a steady-state is formed. Weather then produces noise on the climate signal.
It does not matter that it “is not in thermodynamic equilibrium with itself” as that is what causes weather – NOT climate. This comes back to the idea that weather is a runaway train and creates it’s own climate –it does not. It is the Drivers external to the Earth and within it (chiefly albedo) and in the longer term, orbital eccentricity, that determine the climate. That, yes, is chaotic but it is internal to the system and apart from initiating feed-backs it will still result in ultimately the same emission at TOA (averaged temporally/spacially).
Analogy: Put a known quantity of water in a pan on an electric hob and apply heat. The water will arrive at boiling point in a known amount of time using a known amount of electricity (given known initial temp, volume and atm press). Yes? What we don’t know – cannot know (predict) is the movement of the molecules in the pan that convectively/turbulently move heat around that pan. That is the chaos akin to weather on Earth —- and as I said the outcome of the water reaching a known temp with a known amount of energy IS predictable. You see, the chaos (or if you like non-thermal balance is INTERNAL ) it merely moves around heat that is already in it – it cannot change the ave temp of the whole system.
So it is with the Earth – know the solar constant and the Earth’s albedo, it’s atmospheric GHG effect and knowing also heat stored in the oceans we can/do work out the direction of the average temp of Earth is going.
There are some inponderables – such as cloud feed-back effects but they cause radiative warming as well as reflective SW cooling, and current studies are undecided on which effect dominates.
Other feed-backs are either +ve or small.
“deviates from a black body distribution and so has no one temperature [6]. There is also no unique “temperature at the top of the atmosphere”. The temperature field of the Earth as a whole is not thermodynamically representable by a single temperature.”
Of course there is “no one temperature” – I didn’t say there was – we are talking averages here – the system temp. Yes, it is thermodynamically representable by a single temperature – that’s basic physics of a system in equilibrium in space (which is should be bar any changes to the largely external forcings I’ve mentioned).
For radiative balance everything CAN be boiled down to one temp after working out solar in – IR out + Solar reflected.
Also I’ve studied more tephigrams, or if in the US, SkewT profiles of the environmental atmosphere in all parts of the world to know that the TOA cannot be represented by “one temp” – again we can use an average though.
The atmosphere isn’t independent of the Earth – the whole thing is the same system radiatively from/to space.
The atmosphere is also heated by conduction/convection/LH take-up/release – but that has just taken the heat elsewhere! It still has to be radiated away to space – which is what the climate system MUST do.
Having no radiative gases means all radiation can pass through unimpeded – so solar comes in and terrestrial IR goes out, both equally unimpeded. There are radiative gases the triatomics (H2O, CH4, CO2 and O3) make the atmosphere part of the radiative system and not independent of it.
“2. To talk about the Earth’s ‘climate’ as if it was independent of its Geography, let alone its Geology is absurd. I’ll list some of the ‘essential factors’ below:
a. Oblate spheroid, rotating on axis creating uneven “energy in”! We know these as the seasons! Precession is in flux.”
It is independent of it’s geography in the “Climate” at study we are talking of the long-term climate over the next century or so – and just as the shape of the pan in which the water is boiled in my analogy above does not matter – neither does Earth’s geography. That churns about the internal energy before it is radiated away to space. The Radiative balance of the Earth does not care where the heat escapes to space from – whether straight to space the IR window or from land/mountains or sea, or air in any part of the atmosphere.
“b. Diameter and hence, speed of rotation at equator faster, creating Coriolis effect, which dominates the global circulation patterns (The trade winds). Creating the major climatic zones (Desert/Jungle)”
Look, I’m a retired Meteorologist (you know – same as was/is Anthony’s profession)
So No need to teach me the above.
Again that is irrelevant – we know the amount of Solar energy hitting the TOA (top of atmosphere) ie 342W/m^2 and we can measure what goes out – there is a disparity of ~0.6 +/-0.2W/m^2. It is the total system (easily quantified) that is important – and not the variation of temperature of various climatic regions. We need to know long-term and all can be averaged out – pan of water analogy.”
GCM’s seek to quantify as much of the chaos within the system as possible – because that is what science always seeks to do – however apart from quantifying feed-backs all it will do is reduce the error bars – a general trend could be discovered without. Just as average global temp correlates the Milankovitch cycles ( bar some feed-back effects ). And also, I may say with CO2.
“c. The shape and geographical distribution of land masses and bodies of water (All of which are in flux).”
As above.
“e. The Earth’s magnetic field, without which, there would be no atmosphere (It would have blown away in the solar wind)”
? No connection with climate.
“f. The Moon and it’s effect on rotation and tides”
Some minor effects again with gravity waves imparted upon the atmosphere/oceans but generally a constant.
“g. The earth’s elemental composition. Carbon is the fourth most abundant element in the universe yet most of the Earths is locked in the core. “Energy in” and carbon-dioxide are utilised by all life on earth and much is stored as biological mass via photosynthesis.”
Correct but what has this to do with the climate other than that described by the carbon cycle which is taken into account by GCM’s
“I probably didn’t point out the most important but you get the idea.”
Look I do, please don’t take this explanation of your points the wrong way – they are all common mis-perception of the way works – ultimately the Earth in managing it’s energy budget from the sun then out again to space. It is ONLY the balance of that equation that matters in the end.
Please watch this video from NASAEarthobservatory 3:35min
Note there is NO mention of anything happening within the Earth to interrupt the basic balance..
BTW: there is nothing here I’ve said that you will not find in text books etc.
Also: I can say no more on the subject.
Thanks TB,
Are we sure though that this statement is actually true?
CERES admit that the absolute measurement errors on incoming SW and OLR is greater than 1 deg.C. The quoted disparity of 0.6 w.m2 is actually fudged to agree with models ! This would be the key peace of evidence that the Earth is warming if only it were true. However the empirical data doesn’t actually prove that. It is just too convenient for climate scientist to state that CERES measurements apparently confirm their models. But they don’t.
It is a circular argument !
TB says:
“The Earth is not in equilibrium – at the moment, which is why sea/air temps are rising. However , as it lies in the vacuum of space as an ultimate sink for the Solar energy it receives, basic physics says it should be…”
Wrong. TB preposterously claims that the climate was always in equilibrium – until human activity presumably threw everything out of kilter. That is the thoroughly debunked Michael Mann argument, as expressed in his original Hokey Stick chart.
Let’s hear whether the climate has just begun changing, from the world’s preeminent Climatologist, the director of atmospheric studies at M.I.T., who has more than 200 peer reviewed climate papers to his credit:
Now, who should we listen to? The world’s foremost climatologist? Or to someone who remains anonymous while claiming to have credentials? Readers can decide which one is credible, because they are saying completely different things.
Clive 4:10pm: “… the empirical data doesn’t actually prove (a disparity of ~0.6 +/-0.2W/m^2.)”
Not all circular. The Stephens et. al. 2012 imbalance discussion points to the thermometer measured upper ocean energy content changes as the source for this figure with 95% confidence interval (not the GCMs). The cite points to Lyman et. al. Nature 2010 measured for the period 1993-2008. It is reported CERES data with higher uncertainty tends to trend reasonably in same amount.
2003 to 2008 Argo data suggests 0.77 +/- 0.11 W/m^2 global ocean or 0.54 W/m^2 entire Earth. So the various data are good for now but climate variables can change per a certain MIT director 1:56pm.
I expect career level funding will continue in order to monitor the changes.
TB says:
December 12, 2013 at 12:44 pm
Firstly, thank you for taking the time to respond point for point. These were the first to come off the top of my head! It was very early in the morning here and I just wanted to raise issues that seemed to me, are often glossed over by experts. I am always aware that this is an open forum and my posts are written to the readers as much as to an individual or avatar. It has worked out well in this case, because you have teased out issues that are important to me as a layman and hopefully to others as well. I believe I understood your position before making my post and I think you understand mine. What I want to get at, is to bring these two arguments closer together!
I do agree and accept Radiative Equilibrium as a describe by the Stefan–Boltzmann law (S-B) for a black body.
The general case for a grey-body appears to allow for albedo but as it is described as ’emissivity’ it is not entirely clear to me at least, if this is independent of GHG emissivity (As a separate calculation is usual). However, I also agree, in the case of the Earth, that since the emissivity of radiation by Greenhouse gases is reduced more than the absorptivity, the equilibrium temperature is higher than the simple black-body calculation estimates.
What I have difficulty with, is the derivation of the variables and assumptions made about constants when applied to the Earth’s climate.
To begin, I find the way the equations are often used, tends to collapse time, exaggerating stasis in order to get to equilibrium. I’ll come back to this point.
The important variables that move the calculations away from the theory, for me, are albedo and GHG emissivity.
In terms of time, when is the albedo calculated? It is clear, you don’t mean geological time, nor ancient historical time but do you mean in the last century, this decade, this past year or today? I’m not being trite, I do wonder because it is clear that a vast range of average temperatures are possible due to the REAL difference in albedo documented on the Earth over time.
TB said:
“It is independent of it’s geography in the “Climate” at study we are talking of the long-term climate over the next century or so – and just as the shape of the pan in which the water is boiled in my analogy above does not matter – neither does Earth’s geography. That churns about the internal energy before it is radiated away to space. The Radiative balance of the Earth does not care where the heat escapes to space from – whether straight to space the IR window or from land/mountains or sea, or air in any part of the atmosphere.”
To my point about the Earth sciences 😉
ALBEDO is geology and geography, it is earth, snow, desert, forest, crops, ocean and CLOUDS as I’m sure you know, of course. This gets back to the issue of time scale in relation to radiative equilibrium. To be clear, WHEN is the equilibrium moment for albedo derived? The equation seems to hide CHANGE in the emissivity term, if it is taken to be albedo and albedo changes over time. I am aware of the average figures for albedo and as I say, I know that it widely varies, locally across the surface. We both agree on this. It is it’s temporality that I have issue with. If the emissivity is changing, is it proper, to claim radiative equilibrium?
TB said:
“Put a rotating object in a vacuum and heat it with an IR lamp. Comes a point when the object gets no hotter as the S-B law ensures a certain temperature it must reach such that radiation received = radiation emitted. Simple as that.”
On a lighter note, I have had a hell of a time getting my spit roast to obey the S-B law! 😉 My modifications to tilt the axis of rotation, just made it worse but I did discover that by moving the heat source further away I could go from cooking to not cooking!! The “food to charcoal” experiment is an interesting one. The problem with that experiment was that my ‘object’ kept losing mass! That equilibrium sure is tricky stuff! 😉
On the serious side, calculations of effective temperature, for a planet, do take rotation into account.
To be continued….
Next episode:
GHG emissivity, how IS it calculated 😉
I’ve got to check that roast, again!
This is becoming too long winded anyway!
cheers,
Scott
But Table VI shows that Callendar massively underestimated future CO2 concentrations. For example, he assumes the mean p(CO2) in the 21st century will be 3.3 parts per ten-thousandth of an atmosphere, i.e. 330 ppm. This level was exceeded in the 1970s. Callendar also assumes that the mean concentration in the 22nd century would be 360 ppm – a level exceeded in the 1990s. His mean temperature estimates for the 21st and 22nd centuries are 0.39 and 0.57 (above mean 19th century temperatures). An increase in concentration from 330 ppm to 360 ppm represents a forcing of around 0.4 w/m2.
Callendar, then, appeared to think climate sensitivity is around 1.7 degrees per 2xCO2 – or a bit higher than the generally accepted “no feedback” sensitivity.
John Finn says:
December 12, 2013 at 1:50 am
“As CO2 accumulates in the upper DRIER and colder atmosphere the average emission altitude is increased. In other words more energy is emitted from a colder region. The rate of emission will, therefore, decrease (S-B Law).”
Not true.
In a parcel of air, each CO2 molecule is surrounded by 2500 other molecules, 99% of them N2 and O2 which are IR inactive. The temperature of the air parcel is set by conduction, convection, and latent heat transfers from water. The lapse rate measures the fact that the air cools and thins with altitude.
An air parcel in the lower troposphere is compressed and densely packed. When a CO2 molecule absorbs a photon, the energy is instantly lost through contact with other molecules. Thus CO2 near the surface simply adds a miniscule amount to the huge movement of heat upwards by other means.
At the top of the troposphere, an air parcel is thin and spread out. The CO2 molecule is able to re-emit the photon in a random direction. If downward, the photon is re-absorbed in the parcel below. If upward, the photon will eventually escape to space (after a few nanoseconds). In this part of the atmosphere, IR gases function to radiate energy into space.
Some warmists claim that adding CO2 pushes the radiating level higher and to a lower temperature, thus reducing the amount of heat emitted. This is false, since NIMBUS observations show CO2 emits at the tropopause, where temperature does not vary with altitude.
Scott Wilmot Bennett says:
December 13, 2013 at 1:39 am
TB says:
December 12, 2013 at 12:44 pm
Firstly, thank you for taking the time to respond point for point. These were the first to come off the top of my head! It was very early in the morning here and I just wanted to raise issues that seemed to me, are often glossed over by experts. I am always aware that this is an open forum and my posts are written to the readers as much as to an individual or avatar. It has worked out well in this case, because you have teased out issues that are important to me as a layman and hopefully to others as well. I believe I understood your position before making my post and I think you understand mine. What I want to get at, is to bring these two arguments closer together!
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No problem Scott – I learn something new myself every time I respond to a post.
Yes, I think many people get caught up in the “but they can’t even forecast the weather for the weekend” type of thinking – but that’s comparing apples and bananas. The ultimate causes of planetary temperature come down to it’s radiative balance sitting between the Sun and Space. I hope the boiling pan of water resolved the red herring of internal chaos (transitory climate cycles) for you.
The rest is working out feed-backs and quantifying error bars (probability ranges). Also the IPCC wants estimates of what various scenarios entail.
“However, I also agree, in the case of the Earth, that since the emissivity of radiation by Greenhouse gases is reduced more than the absorptivity, the equilibrium temperature is higher than the simple black-body calculation estimates.”
I always try to think of these things in physical terms…
My conception is that GHG’s simply act like a fog to IR as it comes up from the surface. Imagine it as you walking through it with a torch the light from it is scattered around. ( BTW the ratio of condensed water to N2 and O2 molecules is of a high order ) The fog remains thick for a while until we reach around 7km along the road and then it starts to thin (coincides with the thermal equilibrium level) and the fog finally clears at TOA.
For a photon in that torch beam there are many “collisions” through that “thicker” fog and it “bounces” around – (introducing another analogy) like a ball in a pin-ball machine. Multiple collisions – some return that photon to the surface to “bounce” up again. This will have an attenuating effect on the overall “current” of IR photons that are radiating to space. A slowing of the flow. And like a dam in a river the flow will “back-up” behind to a level dependent on the size of that “dam”. On earth that means that surface is warmer that it otherwise would have been and S-B says that higher temp will emit more photons to overcome the “dam” or “fog” and maintain equilibrium.
“The important variables that move the calculations away from the theory, for me, are albedo and GHG emissivity.
In terms of time, when is the albedo calculated? It is clear, you don’t mean geological time, nor ancient historical time but do you mean in the last century, this decade, this past year or today? I’m not being trite, I do wonder because it is clear that a vast range of average temperatures are possible due to the REAL difference in albedo documented on the Earth over time.”
In GCM’s they model the Earth at T+0 as closely as possible to it’s real state and project forward in say ½ hr steps (often from a past point because the models take a time to “spin-up”)
There are parameterisations for albedo that model land-use and topography/geography and the most important one – snow/ice. This will be modeled to advance/recede on a seasonal basis. However during historical past simulations of climate (done to verify the models performance with a real climate system) then these will be changes to match known values of the time.
Again we are not predicting regional temps across the globe because of this albedo – rather using it to quantify SW reflection (not emission) from the total surface area – but also from aerosols and cloud tops.
Note also snow/ice does more than just reflect SW it acts as an insulator to the ground and allows much lower night-time minima as a result + emits more IR radiating down from the lowest layers of atmosphere to space (in still/dry/clear conditions this leads to a VERY marked surface inversion).
“To be clear, WHEN is the equilibrium moment for albedo derived? The equation seems to hide CHANGE in the emissivity term, if it is taken to be albedo and albedo changes over time. I am aware of the average figures for albedo and as I say, I know that it widely varies, locally across the surface. We both agree on this. It is it’s temporality that I have issue with. If the emissivity is changing, is it proper, to claim radiative equilibrium?”
By emissivity – you mean the ability of a molecule to emit radiation in a specific range of wavelengths. Hence “grey body. GHG’s in the atmosphere absorb/emit in discrete bands of radiation. The two are held to be equal such that IR emitted to space is averaged out to the ratio of GHG’s (including WV) known to be present in the atmosphere and taking them to be well mixed throughout. Clouds will be modeled via a simple quantification of temp and rel. hum. for each grid-scale box.
I don’t see it as equalising albedo against emissivity but I suppose you could look at it that way.
TB said:
“I can say no more on the subject.” ☺
John Finn 5:48am: Concur.
Interesting the basic science in Callendar 1938 is ~same as in modern text books on the subject, so not as much progress in this field (despite much effort in recent decades) as in many other fields.
Given the title of the top post, the obvious issue of the futility of very expensive GCMs (with advantages of modern observations) performing worse than the simple projections of this paper is – remarkable.
TB says:
December 12, 2013 at 4:59 am
——————————————–
TB,
your response has fallen into they typical format of radiative greenhouse defenders –
“The surface will not be uniform. Some parts will be hotter than others, and this will set up local turbulence/convection. Growing and taking heat from the tropics to colder parts. The N2 will be in motion.
There will be some energy exchange from this convection but on balance, heat flux to the N2 goes nowhere. For N2 cannot emit it to space. It can only conduct it back to the surface (somewhere).”
– the hand waving that somehow strong vertical tropospheric convective circulation can continue in the absence of radiative gases. It cannot. Radiative cooling at altitude is critical to this circulation.
Conductive heating and cooling of the atmosphere at surface level will never create enough “turbulence” to drive strong vertical circulation over the 10 to 15 km height of the troposphere.
Radiative cooling at altitude is critical to driving strong vertical tropospheric convective circulation. The amount of energy being radiated to space from the upper atmosphere is more than TWICE the energy being absorbed by the atmosphere from incoming solar IR and outgoing surface IR. This is because radiative gases at altitude are not just emitting energy from absorbed IR to space, but also all the energy the atmosphere acquired from surface conduction and the release of latent heat from condensing water vapour.
Due to issues of IR opacity, the ability of radiative gases to heat the atmosphere is an inverse logarithmic function of their concentration. Their ability to cool the atmosphere however is a far more linear function of their concentration.
And the ability of radiative gases to slow the cooling of the “surface”? Far less than claimed. Incident LWIR can neither heat nor slow the cooling rate of liquid water that is free to evaporatively cool. That would be 71% of the earth’s surface. Go back and check the calculations of the pseudo scientists, they calculated the effect of LWIR on the oceans based on their emissivity. This works for most materials, but not liquid water.
Radiative gases do absorb IR and heat the atmosphere. Radiative gases do emit IR back to the surface slowing the cooling of the land surface only. However radiative gases primary role in our atmosphere is cooling, via LWIR emission to space. Adding radiative gases to the atmosphere will not reduce the atmospheres radiative cooling ability.
Trick says:
December 12, 2013 at 6:18 am
Konrad 2:57am: “(interfering with arrival of heat) is exactly what radiative gases are doing.”
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No Trick, that trick won’t work. The line I cited was –
“without interfering with the arrival or distribution of the heat supply”.
– you left out the “distribution”.
Why was that?
Oh, that’s right, radiative gases play a critical role in driving strong vertical tropospheric convective circulation, the most powerful method of mechanical energy transport in our atmosphere.
Konrad 5:23pm: “- you left out the “distribution”. Why was that?”
Thanks for asking. For one, you didn’t define “distribution”. The reason I see is defn. “distribution” is part of the Callendar 1938 science conclusions and as discussed in the exchange between Sir George Simpson and the author. “Distribution of heat supply” allows the global system to be nearly balanced and in part for real global convective, conductive, radiative energy transfer (transport) to be superposed for global surface Tmean calculations.
The “distribution” you mention has no effect on the mostly non-overlap shown in Fig. 7-11 in TB’s Chapt. 7 link from which your 2:57am assertions are empirically shown incorrect. Nor does “distribution” influence global f term in eqn. 7.16. Your unmet challenge remains to show where Chapt. 7 science (theory and empirical) actually becomes false. Assertions won’t work.
Strong vertical convective circulation does not dump energy to space, dumps it to the atm., i.e. “distributes” energy within the control volume of interest. Only radiative transfer dumps control volume energy out to deep space.
BTW, there is a great paper of the emissivity of ocean water over the Pacific; I will let you find it as a challenge. Ask if you can’t since it empirically shows your assertion clipped here to be incorrect on Earth scales: “Incident LWIR can neither heat nor slow the cooling rate of liquid water that is free to evaporatively cool.”
IOW, the paper confirms the emissivity/absorption of great expanses of ocean water to be reasonably correctly used in TB’s linked Chapt. 7 and Callendar 1938.
Trick says:
December 13, 2013 at 7:11 pm
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“Your unmet challenge remains to show where Chapt. 7 science (theory and empirical) actually becomes false. Assertions won’t work.”
I have met this challenge many times. But one more time for the record. You refer to TB’s link –
http://acmg.seas.harvard.edu/people/faculty/djj/book/bookchap7.html#13581
The problem here is not figure 7-11. Nowhere on this blog or any other have I ever disputed that radiative gases absorb LWIR. So why point to figure 7-11? My claim is very simple, figure 7-12 is utter tripe, as is any calculation based on it. Figure 7-12 shows a typical two shell radiative model that cannot possibly model the main method of energy transport in our atmosphere.
So is there anything wrong with the maths is figure 7-12? No. As I have demonstrated before, other readers can do as I have done and build a physical experiment that proves the radiative physics of the two shell model –
http://i44.tinypic.com/2n0q72w.jpg
http://i43.tinypic.com/33dwg2g.jpg
http://i43.tinypic.com/2wrlris.jpg
-It works. The target plate in chamber 1 reaches a higher temperature. Hooray! AGW is proved! No. Wait. Just like Callendar we haven’t dealt with the reality of a moving gas atmosphere.
But the experiment for that is even more simple –
http://i48.tinypic.com/124fry8.jpg
Two EPS foam insulated gas columns 1m or higher with equal flow rates of heating and cooling water running through their aluminium heat exchanger tubes. Start both columns at the same temperature and run until they reach equilibrium. Despite equal temperatures of the exchanger tubes in both gas columns, one column stabilises at a far higher equilibrium temperature. Once equilibrium temperature is reached, equal amounts of energy can be flowing into and out of each column, but one has a higher average temperature.
Remember when you couldn’t work out the answer to this problem Trick? The Internet does. Forever.
You wrote –
“Strong vertical convective circulation does not dump energy to space, dumps it to the atm., i.e. “distributes” energy within the control volume of interest. Only radiative transfer dumps control volume energy out to deep space.”
– As you would be well aware nowhere on this blog or any other have I claimed that tropospheric convective circulation transports energy outside the atmosphere. All I claim is that the altitude of energy entry and exit from the atmosphere has a great effect on the average temperature of the atmosphere. Only radiative gases can provide energy loss from our atmosphere at altitude.
As to this –
“BTW, there is a great paper of the emissivity of ocean water over the Pacific; I will let you find it as a challenge. Ask if you can’t since it empirically shows your assertion clipped here to be incorrect on Earth scales: “Incident LWIR can neither heat nor slow the cooling rate of liquid water that is free to evaporatively cool.””
– I am well aware of the ship borne non peer review study that (Un)RealClimate tried to use to cover up the critical flaw in the radiative greenhouse hypothesis. This study used a MODIS instrument and submerged temperature sensors to try and determining the change in cooling rate of the ocean in response to changes in downwelling LWIR flux. This piece of tripe is rarely cited now. The flaws were obvious. The scatter plot was atrocious. The only way they could get a line through the “mist” was to merge day and night readings. Why didn’t they use night only and avoid low angle of incidence SW backscatter from clouds? We all know that. Incident LWIR cannot heat nor slow the cooling rate of liquid water that is free to evaporatively cool.
Again the experiment to prove this is simple –
http://i42.tinypic.com/2h6rsoz.jpg
Most WUWT readers can easily replicate this for themselves. My challenge to you Trick. Provide a simple experiment that WUWT readers can build and run for themselves that shows incident LWIR heating or slowing the cooling rate of liquid water that is free to evaporatively cool.
You can’t can you Trick?
TB, Trick and Konrad refer to a link on a website at Harvard.
The link discussed above is to Introduction to Atmospheric Chemistry by Daniel J. Jacob. Chapter 7 discusses the “greenhouse gas effect”, explaining the notion in consensus terms. However, in the text, the author presents empirical facts that dismiss alarmist claims.
For instance on page 129:
“By contrast, in the strong CO2 absorption band at 15 mm, radiation
emitted by the Earth’s surface is absorbed by atmospheric CO2, and
the radiation re-emitted by CO2 is absorbed again by CO2 in the
atmospheric column. Because the atmosphere is opaque to radiation in this wavelength range, the radiation flux measured from space corresponds to emission from the altitude at which the CO2 concentration becomes relatively thin, roughly in the upper
troposphere or lower stratosphere. The 15 mm blackbody temperature in Figure 7-8 is about 215 K, which we recognize as a typical tropopause temperature.”
Hence, any change in altitude at the tropopause does not change the temperature of the emissions.
The author also says, on page 130
“Contrast this situation to a greenhouse gas absorbing solely at 15 mm, in the CO2 absorption band (Figure 7-8). At that wavelength the atmospheric column is already opaque (Figure 7-13), and injecting an additional atmospheric absorber has no significant greenhouse effect.”
Hence, the CO2 effect is already saturated.
Konrad 10:35pm: “Remember when you couldn’t work out the answer to this problem Trick?”
Yes, because your kitchen table instrumentation couldn’t provide the energy in and energy out integrated over the spectrum for the control volume (CV) when I asked (Konrad used 1 thermometer for a temperature field!). Provide that and an informed critical engineer can work out the Tmean answers reasonably close to experiment. Without decent, controlled (expensive!) instrumentation, Konrad conclusions can be anything Konrad wants to support a view.
“..figure 7-12 is utter tripe, that cannot possibly model the main method of energy transport in our atmosphere…”
Please Konrad, show your own theory work on this. Hiding behind assertions won’t work. It is a big deal if you can prove it. Exoplanet atm. science will be changed. Kitchen table uncontrolled experiments aren’t cutting it. They will pay you no attention until you do this. BTW, this 7-12 worked fine for the Soviets in the 60s building the thermometer range for their 1st Venera. It will basically work for exoplanets as is.
Figure 7-12 isn’t what I responded to when I pointed to your clip of Sir George Simpson from the Callendar paper 9:43pm showing your “slight” GHE. The response by GS Callendar in the paper deals with Fig. 7-11.
If you want to change the subject to 7-12, fine.
Figure 7-12 control volume is Earth surface and TOA (“outgoing terrestrial radiation”). You can move energy all you want inside the CV since the counting of energy in and energy out, spatially and temporally avg.d for CV will be unaffected. This is most basic thermo. 101. Strong and weak vertical transport is avg.d out over the spectrum (“outgoing terrestrial radiation”) and surface with no effect on eqn. 7.16. Or show the term that is missing.
As for the paper, try this, no need to build an uncontrolled kitchen table experiment. Right, I can’t – find anything different when properly done:
“Measurements of the infrared emissivity of a wind-roughened sea surface” Hanifin 2005.
Shows the sea surface emissivity vs. wind speed doesn’t vary much (0.98 to 0.984 from 0-10ms^-1), close enough to 1.0 for the f=0.77 in 7.16 to give reasonably 288K. At most the wind speed effect is 0.7K on SST.
Ron C. 6:11am:”no significant greenhouse effect. .. the CO2 effect is already saturated.”
Depends on the meaning of “significant” in number terms. The Tmean anomaly being discussed is on the order of 0.2C per century or recent ocean energy measured imbalance of 0.6W/m^2 out of some 240. I would point to Callendar 1938 Fig. 2 for the log curve; at 400ppm anomaly in C is still not leveled off with increasing CO2 PPM.
Modern curves are similar if you want to cite one.
“..facts that dismiss alarmist claims.”
Callendar 1938 discusses the benefits of increasing CO2 ppm. It is obvious on the ‘net that a view can be formed either way.
Trick
So, it is not alarming. 0.6W/m2 is within the measurement error range, and increasing CO2 has benefits to the planet.
Ron C. 9:01am “..not alarming.”
Dunno. I don’t have a view. If pressed, I’ll go with the top post title. There is a certain futility in long range climate prediction given all the chaotic variables. One should not have a view on the science though; it is easy enough to find & read a good atm. thermo. text book if proficient on the pre-req.s.