Guest Post by Willis Eschenbach
Impelled by my restless curiosity, I’ve returned to the TAO buoy dataset to investigate a claim by Dr. Ramanathan of a “super-greenhouse” effect. The TAO buoys are a number of moored buoys located across the Pacific. The TAO data is available here.
Figure 1. Locations of all of the sites of the TAO buoys, stretching from above Australia on the left, across the Pacific to off of South/Central America on the right.The buoys collect information on some 17 different variables. The graphic is from the data selection page linked to above. Solid blue squares show buoys which record the currently chosen variable (in this case SST). Empty blue squares show buoys which do not measure the current variable.
I am using the sites on the Equator itself because they have the widest variety of data, including rainfall, air temperature, sea surface temperature, pressure, winds, etc.
Now, here’s the statement by Dr. Ramanathan that I wanted to investigate:
The greenhouse effect in regions of convection operates as per classical ideas, that is, as the SST increases, the atmosphere traps the excess longwave energy emitted by the surface and reradiates it locally back to the ocean surface. The important departure from the classical picture is that the net (up minus down) fluxes at the surface and at the top-of-the atmosphere decrease with an increase in SST; that is, the surface and the surface-troposphere column lose the ability to radiate the excess energy to space. The cause of this super greenhouse effect at the surface is the rapid increase in the lower-troposphere humidity with SST; that of the column is due to a combination of increase in humidity in the entire column and increase in the lapse rate within the lower troposphere. The increase in the vertical distribution of humidity far exceeds that which can be attributed to the temperature dependence of saturation vapor pressure; that is, the tropospheric relative humidity is larger in convective regions.
The “convective regions” are the warmer tropical regions where convective thunderstorms are a frequent occurrence. And his claim is kind of logical, since evaporation is in part a function of temperature, with increasing temperature leading to increasing evaporation.
However, my own experience of living in the tropics led me to suspect that contrary to Ramanathan’s claim, the relative humidity (RH) would in fact be lower in the convective areas, and lower during the times of day when there are the most thunderstorms. I thought this for two reasons.
The first is my own experience of a couple of decades of working in these tropical regions. My observations are that before the afternoon thunderstorms come rolling in, the air is often “sticky” with moisture. After the thunderstorms, on the other hand, the air feels dryer. Anecdotal, I know, but I tend to trust my own experience over theory …
The other reason is that although there is a lot of moisture moving around during the thunderstorm regime, it’s mostly concentrated under and inside the thunderstorms, and that moist air is moving rapidly upwards to have the water wrung out of it by the thunderstorm. But in the much larger area in between the thunderstorms, you have dry descending air. This is air from which the water has been stripped by the thunderstorm through a combination of condensation and freezing.
And as a result, my expectation was opposite to that of Ramanatan—I expected that the more convection, the lower the relative humidity.
So, off to the data, with a few digressions along the way around and back. First, let’s look at sea surface temperatures. This is all two-minute data, that is to say the sea surface temperature (actually one metre below the surface) is recorded every two minutes.
Figure 1. The daily average variations in sea surface temperature at eight equatorial Pacific TAO buoys.
Now, I’ve colored the data from light blue (coldest) to red (warmest). Note that this is also in order by location—the further west you go along the Equator in the Pacific, the warmer are the ocean temperatures. Note that the water temperatures rise evenly and fairly rapidly from early morning to a peak at about three pm. Then over the next sixteen hours or so, the ocean gradually cools down again.
There is kind of a subtle oddity in the daily variations. This is that the warmer the ocean overall, the less daily variation there is in the sea surface temperatures. To illustrate this, Figure 2 shows those same daily ocean temperature cycles as anomalies around their respective averages.
Figure 2. The daily variations in sea surface temperature at eight equatorial Pacific TAO buoys, expressed as anomalies about their respective means. Red shows the warmest buoys, light blue shows the coolest buoys.
Curious. The sea surface temperature in the warmer part of the Pacific don’t vary as much on a daily basis as the temperatures in the cooler part.
As might be imagined, a similar situation holds with the air temperatures. The further west you go, the warmer the air temperatures you’ll find. Figure 3 shows the air temperatures at the same buoys shown in Figures 1 & 2.
Figure 3. The daily variations in air temperature at eight equatorial Pacific TAO buoys.
As with the sea, the temperatures increase with the distance west. However, the changes in the air temperatures are more complex, because of the emergent atmospheric phenomena of cumulus clouds and then thunderstorm clouds. This becomes visible when we look at the air temperature anomalies.
Figure 4. The daily variations in air temperature at eight equatorial Pacific TAO buoys, expressed as anomalies about their respective means. Red shows the warmest buoys, light blue shows the coolest buoys.
Figure 4 is perhaps the strongest evidence of the existence of a cloud-based temperature regulation system that I’ve found so far. Let me see if I can explain why. Here’s a graphic showing the situation at dawn …
Figure 5. The general situation in the tropical convection areas in the early morning.
As you can see, at this time of day clouds are uncommon. As a result, Figure 4 shows that the temperature rises very rapidly for a couple of hours after six AM. However, as the day warms up, at some point a threshold of emergence is passed and the first thermal cumulus clouds start to form, resulting in a change of atmospheric state. Within an hour or so, in place of clear skies, there will be a fully developed cumulus field covering the entire surface.
Figure 6. The general situation in the tropical convection areas in the late morning, with a fully developed cumulus state.
In the colder areas, the cumulus do not form as early or as strongly, so they don’t have as large an effect. But as you can see in Figure 4, in the warmer areas there are so many clouds that the temperature actually drops for three hours, from about nine o’clock to about noon. And as Figure 4 shows, the further west you go, the warmer it gets, and the stronger the cumulus cloud effect gets.
However, even in a fully developed cumulus state, there is not continuous cloud cover. The cumulus clouds can be thought of as flags, each one marking an area where there is an upwelling column of air. However, in between the upwelling air columns and their respective clouds, perforce there must be larger areas of slowly downwelling air. And these areas don’t have clouds. As a result, although the temperature rise is reduced or reversed from nine AM until noon, the sun still gets stronger over that time, and at some point around noon the cumulus shield is not enough to stop further temperature rise.
In the afternoon, with the continuing temperature rise, a new threshold is passed and we get another change of state. This one involves the formation of thunderstorms. These astounding emergent entities pipe air vertically at very high speeds, removing heat from the surface and converting it to mechanical motion. They also cool the surface in a number of other ways.
Figure 7. The general situation in the tropical convection areas in the afternoon to night, with a fully developed cumulonimbus (thunderstorm) state.
There is an oddity, which is that when the thunderstorms develop, the albedo goes down. This is because the vertical motion is so fast in the thunderstorms that they have a proportionately much larger surrounding cloud-free area of dry descending air on all sides of them.
Now, I said at the outset that there would be “a few digressions along the way around and back” to Ramanathan. So with those as the digressions along the way around, let me come back to the topic by saying that these large areas of descending dry air are the reason that I thought that Ramanathan was wrong. Remember that I’d disagreed with Ramanathan’s claim, viz:
The cause of this super greenhouse effect at the surface is the rapid increase in the lower-troposphere humidity with SST; … the tropospheric relative humidity is larger in convective regions.
And what do the TAO buoys say about the relative humidity (RH)? Well, here are the daily cycles in RH for the same eight TAO buoys …
Figure 8. The daily variations in relative humidity (RH) at eight equatorial Pacific TAO buoys, expressed as anomalies about their respective means. Red shows the warmest buoys, light blue shows the coolest buoys.
Now, the colors of the buoys are the same. Coldest is light blue, warmest is red. But instead of the RH increasing with sea surface temperature (SST) to engender a “super greenhouse effect”, the reverse is true. As the ocean temperature rises, the relative humidity falls.
How about during the course of the day? My hypothesis regarding emergent phenomena says that the relative humidity should be lowest during thunderstorm time in the afternoon. The next figure shows the RH all of the buoys once again as anomalies, so we can compare their daily variations.
Figure 9. Daily variations in relative humidity (RH), shown as anomalies about their respective means.
Comparing this to the SST, we see that contrary to what Ramanathan claimed, when the SST is largest, the relative humidity is the lowest.
Now, all these findings shown in Figs. 8 & 9 are curious, because Ramanathan clearly believes that relative humidity is invariant under changes in the climate. He says elsewhere (emphasis mine):
A simple explanation for the water-vapor feedback among the early studies of climate sensitivity was the fact that the relative humidity of the atmosphere is invariant to climate change. As Earth warmed, the saturation vapor pressure (es) would increase exponentially with temperature according to the Clausius–Clapeyron relation, and the elevated (es) would (if relative humidity remains the same) enhance the water-vapor concentration, further amplifying the greenhouse effect. Although it is well known that atmospheric circulation plays a big role, a satisfactory answer as to why the relative humidity in the atmosphere is conserved is still elusive.
But according to Figure 8, the relative humidity in the convective zones of the Pacific varies inversely with sea surface temperature. And this is true both for long-term average sea surface temperature, as well as for the daily average temperature variation.
I can’t say that I have any great conclusions from all of this. However, it does appear that the modelers’ claim of strong water vapor feedback rests on the idea that relative humidity stays constant in the face of warming. If these TAO data findings are correct, and if relative humidity more generally is not constant with respect to temperature, it would seem that this would greatly reduce the amount of purported water vapor feedback …
In any case, it would seem to falsify the idea of a “super greenhouse effect” that is driven by relative humidity as Dr. Ramanathan claimed.
Always more to consider, always more to learn.
My best wishes to all,
w.
PS—If you disagree with someone, please have the courtesy to quote the exact words you disagree with. In that manner, we can all understand exactly what you are disputing.
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Sorry, total rubbish. Increased convection means increased latent heat requirement leading to a cooling which is why tropical wet areas are cooler than deserts with zero water vapour. Radiation from a cool area cannot increase the temperature of a warmer one, 2nd law of thermodynamics.
If you challenge the 2nd law then make your fortune and design a perpetual motion machine using the GHE.
To John Marshall: which are the exact words that you disagree with in the post?
Quite clearly, the warmer the atmosphere, or SST, in the tropical Pacific, the lower relative humidity; which reveals Dr. Ramanathan’s statement a crock.
Actually, John, it’s the 1st law that says that.
Johnmarshall, I almost never see where the 2nd Law is necessary to invoke in climate discussions. 1st Law is all that is necessary — net heat-fluxes. W/almost no exceptions, invoking 2nd Law means someone doesn’t know what they’re talking about.
Well you said it.
Your first sentence is good. Your second sentence is a non-sequitor. The Second law is a dangerous thing to invoke because it involves the totality of existence. It is very easy to misapply (especially with radiation, the most misunderstood of heat transfer methods. Specifically, the emitting of radiation is independent from the receipt of radiation. Both of which are net-entropic-positive events. Therefore, yes, a cool body can radiatively warm a wamer body).
Way back in school, thermodynamics was effectively a class about the second law. We lost a lot of potential Chemical engineers who just couldn’t cut it in relatively simple calculations. Pretty much, if you EVER invoke entropy except in musing about the end of times or in calculating engine efficiencies, you are probably misusing it.
“””””….. It is very easy to misapply (especially with radiation, the most misunderstood of heat transfer methods. …..”””””
It sure is, since EM radiation is no more a heat transfer method, than is an ordinary grocery shopping cart.
EM radiation IS a method for transferring ENERGY. All energy is NOT “heat” (noun).
Nor is coal a form of heat, but you can move it from one place to another in a shopping cart, and release some of the stored chemical energy in it in the form of (waste) heat.
Heat requires physical particulate matter for its transport, either by conduction and by convection, and the amount of “heat energy” is directly describable in the form of the purely mechanical motions of that particulate matter. Those same mechanical movements are an essential part of the concept of Temperature.
Only “Heat” energy can change the Temperature. EM radiation is not aware of Temperature and can neither sense it nor change it.
But EM radiation can be (virtually 100%) converted into waste heat energy, but the converse is NOT true.
Heat energy cannot ever be converted 100% to ANY other form of energy. But almost any other form of energy can be converted (irreversibly) into heat.
Consider transferring “heat” energy by conduction along a copper rod between the sun at 6,000 K and the earth at 288 K for a temperature difference of 5712 K over a distance of 93 million miles, or 9.3E7 x 5280 x 0.3048 m = 1.5 E11 meters.
Copper has a thermal conductivity of 400 W/mK.
So the rate of heat flow from sun to earth along the copper rod is:
400 x 5712 / 1.5 E11 = 15.23 microwatt per square meter.
Well that assumes that the rod doesn’t evaporate, or radiate, so it has a thermal guard ring around it to prevent heat loss out the sides of the rod.
Well you can improve the heat conduction to the earth by using diamond instead of copper, since it has a conductivity of 1,000 W/mK. That’s a whopping 37.5 microwatt per meter squared.
But radiation from the sun can with present technology be converted at about 43% efficiency to DC electricity with present solar cell technology.
That electricity can be converted with about 58% efficiency into red or yellow EM radiant energy and beamed back out into space or back to the sun, with almost no atmospheric loss.
So that is solar energy that never ever gets converted to “waste heat” here on earth.
Well you can also convert the solar energy into wood or food or living organisms; none of which would ever be described as “heat”.
That’s why Kevin Trenberth can’t find his “missing heat”. He assumes that all the eM solar radiation arriving on earth is “heat”. It’s NOT heat.
We make all the heat here on earth, and there is not as much heat made as Kevin imagines.
This is exactly why we’re left in this sorry state of affairs, where the AGW movement is free to continue to bulldoze through with their pseudoscientific nonsense. Because they know they’ve got the lukewarmers (the ‘half-sceptics’) to cover their backs, firmly believing (and promoting the idea, like here) that ‘Radiation’ is some kind of magical, celestial entity that is somehow exempt from the 2nd Law of Thermodynamics. Listen to yourself. Read what you just wrote, benofhouston:
“Therefore, yes, a cool body can radiatively warm a wamer body.”
Are you being serious!?
There is no more a bidirectional thermodynamic ‘transfer of energy’ in a radiative heat transfer than it is in a conductive heat transfer.
https://okulaer.wordpress.com/2015/02/19/to-heat-a-planetary-surface-for-dummies-part-4/
“””””…..
Kristian
February 20, 2015 at 3:59 am
……………………….
Because they know they’ve got the lukewarmers (the ‘half-sceptics’) to cover their backs, firmly believing (and promoting the idea, like here) that ‘Radiation’ is some kind of magical, celestial entity that is somehow exempt from the 2nd Law of Thermodynamics. …”””””
A fundamental law of the propagation of electro-magnetic radiation, whether in free space, or through some optical system (any optical system), is the concept of the invariance of ‘etendue’ which is a three dollar French word for ‘throughput’.
At any point in an EM field, the product of an elemental area times the elemental solid angle of the flux through that area, is a constant, and the integral of that elemental product is fixed, and cannot be changed by any optical system.
In optical system design this is manifested by the paraxial (small angle and ray height) quantity n.h.u where n is the refractive index of the medium, h is the ray height from the optical axis, and u is the edge ray angle. This is known as the Lagrange invariant.
Away from the paraxial region, this rule becomes N.H.Sin(U) in a planar system, or the square of that product in a three dimensional system, often referred to as the optical sine theorem . Put into words it expresses the notion that no optical system can form an image whose ‘brightness’ (radiance) is higher than that of the source. Since the rays are reversible (in geometrical optics) this also implies that no system can make an image that is less bright than the source. Well of course practical systems contain media, where the radiation gets absorbed in whole or in part, or splits into several directions.
If the invariance of this quantity were not true, then an optical system that created a brighter (higher radiance) image than the source, could take the energy from a black body radiator source, at some Temperature Ts, and inject it into an image black body at higher radiance, and thereby drive the image body to a higher Temperature than the source body, which the second law prohibits.
One of the first proofs of the optical sine theorem was given by Rudolph Clausius, using this second law demonstration.
The invariance of etendue is a major stumbling block in solid state lighting.
LED die, have very small radiating surface areas, with extremely high radiance values.
When used in some optical system to create a light source of some source area, and solid angle of distribution, the area and solid angle can be exchanged with each other, but the product must remain constant. The only way around this is to employ some statistical or time multiplexing contrivance to make a source appear larger but only for some fraction of the time.
For example, a once cm square source, could be mechanically scanned back and forth over a one square meter area, at high speed, but it would only appear in any location for one millionth of the time, and the eye would perceive it to be a million times dimmer.
Of course you could angle scan it instead with the same result.
In practice, diffuse surfaces or volumes are used to scatter the photons, which is a time multiplexing process. Unfortunately, this always results in back scatter, and wide angle scatter, both of which are loss mechanisms.
In white LED devices, you get one ‘get out of jail free’ card, in that you start with an extremely bright blue LED and you absorb much of the blue light in some much larger area of phosphor, which then radiates the green yellow and red portions of a white light spectrum. But note that you still have a blue etendue problem, so the phosphor also is required to scatter the remaining blue photons as well.
So if those ugly white LED street lights or car headlights bug you; now you know, the engineers have not solved the invariance of etendue problem yet. When they do, the LED headlights will have the same eight inch or so diameter as an ordinary incandescent car headlight.
g
You are both willfully misunderstanding my statements, and George, your use of vocabulary to trash my post simply shows that you really don’t understand what you are talking about. How’s this for a little example:
If you have an isolated body in space at temperature X. No conduction, no convection, no incoming radiation, no nothing. It will radiate energy out via blackbody radiation and gradually lower in temperature.
Now, same situation, but with a second body next to it at temperature X-1. This is also radiating blackbody radiation via the same processes.
Basic thought experiment, which body cools more slowly? As any idiot can see, the second. Why? because it is being struck by the blackbody radiation of the slightly cooler object. This radiation doesn’t magically disappear. Some is reflected and some is absorbed just like every other bit of radiation in existence (photons don’t have memory of the temperature of the body that they came from, which is ENTIRELY THE POINT). The absorbed radiation changes to heat. Therefore, it is perfectly acceptable and correct to say that this body is being warmed by the presence of a colder body. The net transfer is, of course, in the other direction as the warmer body gives off more radiation, and thus even in an otherwise empty universe, entropy rises. However, both objects are warmer because of their shared presence.
You simply give fodder to the alarmists with your willfull misapplication of extremely basic physics and misstatement of the problem.
Uh, correct me if I’m wrong but the 30 degree latitude desert belt may have a higher measured temperature than the tropics (during the day) but measured temperature is not the same as heat. Tropic air has more specific heat because it contains a much higher relative humidity. So, it’s not correct to say that tropical wet areas are cooler than hot deserts when referring to heat. Heat is transferred to higher latitudes from the tropics and no laws of physics are broken.
http://www.knmi.nl/research/CKO/doc/EMIC/ReferenceRun/Images/q_djf.png
http://people.csail.mit.edu/jaffer/SimRoof/Convection/cp-vs-RH.png
“(…) it’s not correct to say that tropical wet areas are cooler than hot deserts when referring to heat.”
But we’re not referring to ‘heat’ (by this I guess you mean rather ‘energy content’, which is equal to the thermodynamic term ‘internal energy’ [U]; thermodynamic ‘heat’ [Q] is energy spontaneously transferred unidirectionally from a hot place to a cold place, not something contained within a system). We’re not referring to ‘energy content’. We’re referring to temperature. Much H2O in an atmospheric column (WV + clouds) will (by observation) on average (annual mean) make the surface beneath cooler (temperaturewise), assuming ToA incident solar is equal. Hence, there is no net radiative ‘greenhouse effect’ (i.e., net ‘absolute warming’ effect) on the surface from having H2O in the atmosphere above it.
“Heat is transferred to higher latitudes from the tropics and no laws of physics are broken.”
Did anyone suggest physical laws to be broken by this process?
johnmarshall,
I am no huge fan of this author, but he is correct on this and you are bloviating.
Excellent independent review.
That lucky old sun has nothing to do, but roll around heaven all day.
Willis, that is a very nice piece of work that uses “DATA” rather than models and theories. It would be very nice if some so called Climate Scientists tried it it some time.
I was not too surpried by the “This is that the warmer the ocean overall, the less daily variation there is in the sea surface temperatures. ” as I supposed that the warmer Seas are already closer to the “Evaporation Point” at the water surface and thus start the cooling process that much quicker.
Is this not more reinforcement of your “Water and it’s evaporation is the Control knob” theory?
I would have guessed that absolute humidity is more important.
Me, too.
Mr. Eschenbach has already done a lot of work for us–which I’m grateful for–but similar plots showing absolute humidity would have been interesting from the greenhouse-gas perspective.
Bingo! +1
Joe and Skywolfe, like you I would suspect absolute rather than relative humidity would be relevant. However, what I was looking at was Ramanathan’s work, wherein he says that the relative humidity should stay constant in a warming world.
w.
Well for me Willis, one of the most interesting tidbits of information, seen prominently in your figs 1,2,3, and clearly non local as evidenced in fig 1, is that the diurnal Temperature cycle isn’t even remotely sinusoidal in shape.
The daily rapid rise in the SST followed by a much slower decay, demonstrates the clear presence of at least a second harmonic frequency component, with a 12 hour period, as well as the 24 hour periodicity.
Consequently any daily reporting of Temperature on a max / min basis or any other twice a day sampling, is a clear violation of the Nyquist sampling theorem, by at least a factor of two.
That means that any reconstruction of the temporal continuous Temperature function, will contain aliasing errors with spectrum components that fold all the way back to zero frequency. Now protestations that a reconstruction of the continuous function is not being sought, and that the samples are only used for an average value, are quite hollow, because that average value, is in fact the zero frequency component of the continuous function and the at least 2 x under sampling means that it is corrupted by aliasing noise.
Given that 70% of the earth surface is water or oceans, it is not comforting to know that the data obtained from twice daily ocean locations, is already rubbish, as far as determining global mean Temperatures. Too bad that the spatial sampling is even less valid.
These buoys of course give a better set of diurnal Temperatures, and satellite scanning improves the spatial sampling, but that doesn’t help all of the data going back to 1850 which purports to be what was real back then, and against which modern data is measured.
I wonder how the fishing is around any of those equatorial buoys ??
g and thanx for another interesting post.
George E. Smith
OK. So the daily temperature is not a sine wave: I will definitely agree, but it is interesting that it is not even a smooth single peak, single drop curve either. (At least not in the tropics, which are 58% of the earth’s surface, and are 58% of the earth’s radiating a surface area – an radiating surface area both hotter the rest the planet and larger than the rest of the planet.)
Thus: Is the 24-hour surface is radiating all 24 hours, but the “hot peak” is a longer, multi-headed hydra of several local peaks, then does that not increase total surface radiation heat loss over the course of a single much greater?
the best the school of contemporary CAGW religion can come up with is +3.0 watts/m^2 average after a forced doubling of CO2 AND an exaggerated water vapor feedback. A longer hotter mid-tropic day would radiate all of the excess away, would it not?
George. You have commented on something I have thought for years. Using average of Tmax and Tmin most likely results in too high a temperature compared to the “mean” but that probably changes with latitude.
Basically, it seems, we really don’t know.
Having plotted a number of station Tmax, min, average, I have very little faith in the meaningfulness of the”average” temperature. Tav isn’t a very good representation in a lot if areas. (IMHO)
Great post by Willis. I assume confirmation bias must be endemic in academia. Why can Wilis find “data” when the “experts” use expected results.
Thanks Willis.
For RACook,
RA, my entire point is that the common twice per day station Temperature sampling, is inadequate for its stated purpose; to determine a global mean number.
For the non communications engineers, the “Nyquist Sampling Theorem” upon which rests the operability of ALL sampled data systems, including ALL modern communications networks, says essentially :
“””” A continuous ‘band limited’ function can be represented (exactly) by a set of instantaneous sampled values of that function, provided the samples are no further apart that half the period of the highest frequency component present in the continuous function signal. “””””
By “band limited” is meant that the frequency spectrum of the function contains NO components having a frequency higher than some value (B), the band limit.
So a signal containing signal variations up to no more than one MHz can be exactly represented by instantaneous values (zero width) of the signal taken at least every 500 nanoseconds, or if you wish at a 2 MHz frequency rate. They don’t have to be uniformly spaced, but they can’t be more than 500 ns between samples.
Then the entire original continuous function can (in principle) be completely recovered from that set of instantaneous samples.
In modern communications systems, all that empty space between those samples, can be occupied with the instantaneous samples of OTHER signals, and they can all be unscrambled and recovered to send to the intended recipient.
Now if a purportedly band limited signal (bandwidth (B)) is sampled at a sample rate 2B, but there is actually information present at a frequency B + b which is “out of band”, it will be found on reconstruction, that the recovered signal, now contains information at a frequency of B – b which is clearly now an “in-band” noise component; called “aliasing ” noise.
Since it is now in band, it can not be removed by any process, without also removing any real original signals that had an in band frequency of B – b.
So if the out of band component is at a frequency of B + B, or 2B, then the aliased noise in the recovered signal has a frequency of B – B, which is zero, and that is the DC value of the signal or average value if you wish.
So even if there is no intention of recovering the original continuous signal, if you only sample at HALF of the minimum Nyquist rate (2B), then you cannot even calculate the AVERAGE value of your samples correctly because the noise spectrum now extends all the way to DC.
So for our daily diurnal Temperature cycle, the fundamental frequency would seem to be 24 hours period. If there is NO signal information at any frequency than one cycle per day, that means the signal must be a 24 hour period sine wave, and two samples per day at 12 hour intervals will suffice.
But as is clear from Willis’ graphs, the saw toothy shape of the SST diurnal Temperature, is clear indication of the presence of a second harmonic component, which is one cycle per 12 hours, and you would need to sample at six hour intervals to correctly get that information.
So the bulk of the surface reporting stations that so far as I know, just give a daily min max or two samples per day, you cannot use those two samples to get the correct AVERAGE temperature for that day, because the signal is NOT BAND LIMITED to one cycle per 24 hours.
And when you consider the SPATIAL sampling of the global Temperature, well you have cause to totally freak out.
Hansen’s one measurement per 1200 km is grossly under sampled, and there is no way in hell, you can obtain a global average Temperature from such garbage data.
Now Willis may have had some special interest in the specific shape of those graphs; he usually does.
But my only comment was related to the fact that they clearly are not any one cycle per 24 hours band limited signals.
And the more complicated shapes that RAC refers to suggest that there is a heck of a lot more high frequency out of band information than just the second harmonic.
There is a recent paper that I read in either Physics today, or more likely Optics and Photonics News, about a controversial type of super resolution optical system, that purports to be able to resolve optical images beyond the wavelength dependent classical resolution limit, or if you will, out of band signal information.
Other readers have pooh poohed the idea, but the authors stick to their guns, and claim it works. …. BUT … They did not claim to be able to COMPLETELY RECOVER the out of band super resolution signal, which Nyquist says you cannot do.
All they claimed, was the ability to “obtain some information about the out of band components.” Well at least that is how I interpret the donnybrook. And maybe that is correct, and maybe the author did not express himself very well in his response to his critics. I decided to not get into it.
g
George,
Yes and Yes, anyone who has spent a significant amount of time measuring hourly temperatures in a single place knows without a doubt that min/max is not a valid sample for average temperature. Having taken hourly temperature measurements in many different places over periods of years, each area, in addition to having a somewhat different average day, has a seasonal component as well.
And yes the fishing around those buoys is very good.
The link to the abstract shows that this is a 20 year old paper. Is someone trying to revive Ram’s idea of ‘super GHE’?
I have 4 decades (several thousand hours) of practical experimentation & observation of the lower atmosphere physics associated with thermals and their associated cumulus clouds. I’m not unique, there are thousands like me across the globe, they’re called glider pilots.
Cumulus clouds are the visible tops of the invisible fountains of air known as thermals. They can be any size from 100m to a kilometer in diameter and a few hundred feet to 10,000ft+ in depth.
Gliders today are equipped with sensitive barometric instruments that can measure vertical movement of the airmass very finely, to as little as a few feet per minute. They are also equipped with data loggers which record, not only a GPS derived location and groundspeed but also the airspeed and altitude thus enabling post flight analysis of the airmass through which the aircraft traveled.
There are literally thousands of flights of duration of up to 10 hours and distances of up to 1500km flown every year, the flight logs of these flights are very frequently available for download and analysis.
Some observations from my personal experience and analysis
In the absence of the special case of cloud streets, the airmass between thermals is frequently neutral, that is as much vertical movement up as down, however, the rate of that movement is a small fraction of that associated with thermals.
A thermal very frequently has a band of strong sinking air, comparable in rate, around the outside of the rising core, the best visualisation is perhaps that of a doughnut in which the air in the centre of the doughnut is rising and the air on outside is sinking. Sometimes the whole doughnut persists from ground level to cumulus, more often the doughnut ascends from ground level to cloudbase (condensation level) at a rate which is small fraction of that in its core.
Both of the above observations apply even when there are no cumulus, i.e. blue thermals, when the air mass is too dry or an inversion prevents the thermal top from reaching the condensation level. and in tipping point phenomena such as thunderstorms where the downdrafts are equally as strong as the updrafts.
I suggest that the primary mechanism for atmospheric pressure regulation in a thermal airmass is the localised descending air associated with the equally localised rising air typically marked by cumulus, not sinking air between thermals.
Thank you for those observations. Anecdotal, yes, but compelling as to the localized decent.
What you describe is for all intents and purposes a Pond Fountain with “Bell” nozzle on the top.
We found the same from years of sailing in the tropics. The area of descending air is localized around the thunderstorm. As the rain from the storm cloud passes on the ocean you often get quite a powerful, cold and dry air descending. Very much like standing under an enormous air-conditioner. Very refreshing compared to the sticky, humid air ahead of the storm. The descending air pushes outward on the ocean and is often quite strong that you can see the effects plainly on the water as large dark streaks, sometimes kicking up spray and froth. Because the flow is downward it is typically useless for sailing, but the turbulence can push the boat around quite strongly. Which is always something, the wind pushing 15 tons around like a toy.
Mostly agree based on my own (anecdotal) 20k++ hours boring holes in the lower/mid troposphere, including a few hundred in sailplanes. Only difference I have is noting that the pattern can change somewhat when a thermal grows beyond the small/medium CU stage to a large CB or full blown thunderstorm.
The FAA data on microbursts for a more scientific view is here: http://lessonslearned.faa.gov/Eastern66/METR4350-microbursts.pdf
Spot on. The propensity of “climate scientists”–academic or self-taught–to indulge in off-base explanations/interpretations of complex geophysical phenomena is enormous. It requires far more than a cursory acquaintance with data and an active imagination to comprehend how nature actually operates. It requires hands-on field experience and an incisive analytic mind. Sadly, the real-world experience of those that dominate the climate debate too often fits in a thimble–with plenty of room left over for their modesty.
+10
“There is kind of a subtle oddity in the daily variations.”
Coincidently, it follows the pattern in the Earth’s Magnetic Field Total Intensity longitudinal change (inverse correlation), most likely irrelevant.
http://www.vukcevic.talktalk.net/EF-test.gif
Map: http://www.ngdc.noaa.gov/geomag/WMM/data/WMM2015/WMM2015_F_MERC.pdf
Data: http://www.ngdc.noaa.gov/geomag-web/?model=igrf#igrfwmm
“There is kind of a subtle oddity in the daily variations.”
Coincidently, it follows the pattern in the Earth’s Magnetic Field Total Intensity longitudinal change (inverse correlation), most likely irrelevant.
———————–
Hello vukcevic.
In my opinion, any correlation, either inverse or not, in it’s own merit it is never irrelevant.
To me a correlation means a possibility of connection between the “entities” correlated .
Stronger and more certain the correlation more likely the possibility of that connection and less likely the possibility of just due to some coincidence.
Definitely worth of investigation and a further research in such cases.
Some times a correlation ends up to be (considered) irrelevant due to the very premature jump on conclusion that it definitely means influence or causation between “entities” behavior and connection or because no any such found there.
Considering this particular correlation that you mention, in its own merit it may or may not be irrelevant to climate.
Please do understand I am not saying or claiming that it is irrelevant, only saying that the possibility of its irrelevance exist.
Again the irrelevance exist, as far as I can tell, only on the point of the overestimating exaggerating or even when dismissing or underestimating the value of that correlation.
So a correlation is irrelevant in a particular given issue or matter (like climate change) while no value found in it in regard to such as, or while that value exist but overinflated.
Said all this, my take in this particular correlation as shown through the evidence you bring and considering further other evidence I have come across here at WUWT concerning the same, is that it seems to be relevant enough for consideration and worth of a scientific investigation, ……..not at all irrelevant as it stands at the moment, …………… without prematurely jumping on conclusions so to speak.
cheers
Hi whiten
I get myself often in ‘hot water’ so to speak, for bringing such things to this blog, but curiosity often gets better of me, and when I get across something interesting, can’t see much point of leaving it on the pc’s hard drive to forgotten for ever.
if the magnetic field loop westward is a co-incidence it would appear to be a long odds co-incidence.
Indeed, it is very long odds. Some bright young spark may find out more. Above my pay grade, however there may be two possibilities her:
– Svensmark: weaker field more energetic GCR, high altitude condensation, atmospheric transparency, absorption, albedo, etc.
– Ionospheric currents induction intensity is a function of Earth’s field strength.
NASA: http://www.nasa.gov/centers/goddard/images/content/154188main_plasma_bands_lgweb.jpg
Dotted white lines mark regions where rising tides of hot air indirectly create the bright, dense zones in the bands.
Three of the bright plasma pairs are areas with lots of thunderstorm activity, in this case were located over Africa, Indonesia and costal region of South America.
“The single pair of bright zones over the Pacific Ocean that is not associated with strong thunderstorm activity shows the disruption is propagating around the Earth”
Enter your comment here…http://www.vukcevic.talktalk.net/NOAA-info.gif
I’ll am already in Mr. Tisdale’s bad book
http://www.vukcevic.talktalk.net/NOAA-info.gif
I’d be surprised if that weren’t the case as water is diamagnetic.
http://www.emerginginvestigators.org/wp-content/uploads/2014/09/Murley_Figure2change_in-_flow_rate_revised_crop.png
Apparent change in saline water’s flow rate due to magnetic field at three concentrations.
Spread that effect over an entire ocean (with its somewhat variable salinity & alkalinity) and I think it’s clear to see how a magnet the size of the planet can change where water wants to flow when other factors aren’t utterly dominating (below a certain depth, for instance, winds don’t matter – and this effect would modify the result of the changing gravitational pull from the moon, et. al.).
It would be weak, for sure, but it must be present.
You are right to dismiss Ramanathan’s fake physics. Firstly, he is in the vanguard of those claiming atmospheric radiant emittance, detected by pyrgeometers, is a real energy flux when it is a potential energy term. Secondly, he fails to understand that the real atmosphere has just a quarter of the humidity that the equilibrium Clausus – Clapeyron equation would give, and it is due to the water cycle.
Increase ‘back radiation’ and net surface IR flux decreases. Thus if it suddenly becomes more humid, net radiant heat transfer is atmosphere to sea surface so it heats up until you get a new evaporative equilibrium, more clouds. Clouds rain harder, reducing humidity, the ocean surface cools. This is Le Chatelier’s principle writ large, an astoundingly stable control system. These people have for 40 years used a puerile view of heat transfer, radiative and IR physics to impose their pseudoscience.
You are correct, but everyone seems to be forgetting that energy transferred into the atmosphere does work expanding the atmosphere which results in cooling the atmosphere. Moist air is also less dense than dry air which also expands the atmosphere. This cooling, Boyle’s Law, is where the extra radiation goes.
Of course it just means that the atmosphere is an energy pump transferring the energy to the poles where the air is compressed, heated, and the energy radiates away.
Beautifully and logically argued. Thanks for the insight, Willis!
“In any case, it would seem to falsify the idea of a “super greenhouse effect” that is driven by relative humidity as Dr. Ramanathan claimed.”
He didn’t
“The cause of this super greenhouse effect at the surface is the rapid increase in the lower-troposphere humidity with SST”
And he is right of course
http://ds.data.jma.go.jp/gmd/jra/atlas/column-1/pwat_ANN.png
http://ds.data.jma.go.jp/gmd/jra/atlas/surface-1/dlrsfc_ANN.png
Seems to me that those two graphs don’t really say what you think they say. The local downwelling radiation depends on both atmospheric composition AND the local atmospheric temperature near the surface. Where the local temperature is higher, even with constant atmospheric composition, the downwelling surface radiation must increase. So the plot of downwelling radiation confounds the temperature and humidity (atmospheric composition) effects. You would need to separately account for the influence of near surface atmospheric temperature to draw conclusions about how atmospheric composition influences downwelling radiation.
“Where the local temperature is higher, even with constant atmospheric composition, the downwelling surface radiation must increase. So the plot of downwelling radiation confounds the temperature and humidity (atmospheric composition) effects.”
True enough. But why wouldn’t you expect, if there is indeed a greenhouse effect, that more water vapor per unit volume would increase downwelling radiation? Is there some reason to doubt that?
Joe,
There is no reason to doubt some effect. But those two graphics don’t tell you what the magnitude of the water vapor (alone) effect is…. the very strong temperature effect is confounded with the water vapor effect.
Ah, maybe I see what you mean. Yes, you’re saying, increased temperature does on average increase absolute humidity if not relative humidity. And that by itself does (loosely speaking) increase the “resistance” that radiation from the surface encounters in reaching outer space. But that effect may be accompanied by countervailing factors, such as albedo increases and enhanced latent-heat transport through much of that increased optical distance. Therefore, those maps tell us nothing about the size or sign of the net feedback.
It’s part of the familiar discussion. Everything else being equal, increased carbon-dioxide concentration raises the surface temperature required to return into space the energy the earth receives from space. In turn, that increase would raise the absolute humidity, which, absent further effects (such as a slightly reduced lapse rate) would increase the required surface temperature even further. You don’t question that; you at least provisionally accept that these effects constitute positive feedback (or, from the outer-loop point of view, less-negative feedback). What you’re pointing out, though, is that the maps don’t separate such positive-feedback effects from attendant negative-feedback effects, such as (arguably) albedo and more-efficient latent-heat-transport bypassing of the radiative path.
More generally, I think you may be saying, those maps don’t tell us whether the surface-temperature increase required by increased carbon-dioxide concentration is greater or less than it would be in the absence of water-vapor and other knock-on effects.
Yes, but if you look at a temperature map you will see the correlation is between LW and vapor, not between LW and temperature. Compare Sahara with the ocean around Indonesia for instance.
lgl,
So to get a more complete picture of the humidity influence you need to show the surface temperature graphic as well, right? You didn’t show that. You appear to claim that the two graphics support: ““The cause of this super greenhouse effect at the surface is the rapid increase in the lower-troposphere humidity with SST”. They sure don’t do that very well.
What you showed (down-welling radiation and water vapor), ignores the influence of local atmospheric temperature on down-welling radiation…. which has to be very large. I am not saying that there is no water vapor effect on down-welling radiation (there has to be!), I am saying the graphics you showed don’t demonstrate that clearly. In addition, the graphics are annual means, which makes a lot more sense over the tropical ocean, with little seasonal temperature change, than it does over the Sahara….. where winter and summer temperatures (and down welling radiation!) are very different. The Sahara is quite pleasant this time of year… not so in July.
Downwelling long wave radiation causes surface evaporation and cooling, it is not absorbed below the surface.
OK, found a temp map with better resolution than the JMA map
http://www.abc.net.au/science/slab/elnino/img/gsst.gif
So clearly, “The cause of this super greenhouse effect at the surface is the rapid increase in the lower-troposphere humidity with SST”. But it’s a feedback loop so one can also say the cause of the high SST is the super greenhouse effect.
Your charts are drawn at a planetary scale and show that the areas with increased precipitable water coincide with the ascending branches of the Hadley cells which circle the Earth near the equator, and are the drivers for the general circulation of the Earth’s atmosphere.
Willis, OTOH, is addressing the mesoscale convection system (MCS), which feature updrafts of warm moist air and downdrafts of relatively drier cooler air.
Both are valid observations, depending on scale.
I didn’t read the paper, so was Ramanathan merely “re-explaining” Hadley cell circulation (moonsoon troughs etc)? Or was he addressing mesoscale convection circulation?
Also, longwave radiation shown is strongest at the equator because the radiance is proportional to the incidence of solar rays (Lambert’s Cosine Law).
There is a curious decrease in longwave over Africa and Brazil. Can be seen more clearly in this Ceres imagery (which also shows a similar decrease over Indonesia) Why is that?
http://www.exploratorium.edu/climate/atmosphere/data/ceres2-2.jpg
Could it be photosynthesis, which is somehow (waving my hands) ‘sequestering’ the radiation and storing it in plants and releasing it as CO2?
Johanus
February 18, 2015 at 6:24 am
Interesting. The CERES satellite imaery definitely shows significant and precise correlation between “deciduous and evergreen trees (Canada, mountain and hilly North America) and and taiga forests (Canada and western Europe and Russia/Siberia) and farmland (US, Canada, WE, and north India) and jungle (Congo, sub-sahara Africa, Malaysia and all far east island (between island ??), and the Amazon basin. Less vegetation (south Brazil highlands for example, SW US (CA, AZ, NM, TX) show up as well.
Yes, it is interesting.
The decrease in longwave over Africa and Brazil and Indonesia is caused by all the high clouds there.
http://ds.data.jma.go.jp/gmd/jra/atlas/surface-1/hcld_FEB.png
“… caused by all the high clouds there”
Hmm. You’re showing us “high-level cloud” plots from the JRA-25 Atlas which is a 25-year reanalysis (i.e. modeled global fill-ins).
http://ds.data.jma.go.jp/gmd/jra/atlas/eng/atlas-tope.htm
The “high-level” cloud plots do partially coincide with the ‘curious’ Ceres negative long-wave anomalies, but also extend over the oceans. So why don’t these oceanic high-level clouds decrease the surface long-wave?
Why not show us the “low-level” clouds, where most of the dynamic weather takes place?
That doesn’t follow. What your graphs show is that rain increases with cloudiness. Pretty much any child of 5 could tell you that.
The map shows vapor, not rain.
Actually, according to the JRA-25 specs, the precipitable water value is computed from microwave (SSM/I) sensors, which can distinguish the different phases of water, e.g. ice crystals, so is more informative than the IR water vapor (WV) signal (6 microns)
http://wcrp.ipsl.jussieu.fr/Workshops/Reanalysis2008/Documents/V1-101_ea.pdf
Here’s METEOSAT’s WV loop over Africa. Note the westward motion of the “monsoon trough” at the equator which accounts for most of the WV seen here. The dark areas represent the strongest IR signals at 6 microns, i.e. from the surface radiating into space (i.e. little or no absorption, so no WV). The grey and white areas represent areas of strongest absorption of the upwelling IR by WV, with white indicating nearly total absorption by WV. (So think of it as a kind photographic ‘negative’ image).
So you can actually see the Greenhouse Effect in action, at least for water vapor. And forecasters would be crippled without access to this kind of water vapor imagery. WV has a tremendous impact on weather (and hence) climate.
Would it be possible to see CO2 similarly “in action”, passively, at 4 or 12 microns? Apparently not. None of the weather satellites have channel for this, so apparently it’s too tenuous to render into any useful images, implying that it doesn’t have a great impact on weather or climate, like WV does.
Please correct me if I’m wrong about this. I think we would all love to see a live, passively received “CO2 vapor” loop. OCO2, the recently launched CO2 observatory uses a much more complicated method, involving transmission spectroscopy of reflected short-wave sunlight, to detect and image atmospheric CO2.
… and here’s the METEOSAT WV/IR loop that I forgot to insert:
http://www.eldoradocountyweather.com/current/satellite/eastern-atlantic-ocean-wv-satellite-loop.html
MODELS ??
It appears that landmasses are blocking the “natural” cycles of global humidity and temperature. This calls for a geo-engineering solution to remove those dangerous landmasses. After all, it would probably be easier than eliminating the use of fossil fuels.
Willis,
Very nice analysis. It looks to me like the daily variation in air temperature and the daily variation in relative humidity could be used to calculate the variation in absolute humidity at the surface (using Clausius-Clapyron, ~7% increase in water vapor pressure at saturation per degree C increase in temperature). It is only the absolute humidity level which influences radiative transfer. I suspect you will find very little change in absolute humidity near the surface…. which would appear to contradict the proposed “super-greenhouse” effect.
One must assume a greenhouse effect exists before a super greenhouse effect can be relevant. If the greenhouse effect is zero, super sizing it will still leave it at zero.
One of the many problems with greenhouse earth ideas is that of heating occurring only from the surface up. Energy is absorbed at every level in the atmosphere though. In fact the most energetic radiation will be absorbed at the boundary of space and less and less energy will be absorbed per molecule as one decends towards the surface.
Our surface is simply an area where the remainder of suns energy is absorbed over a thinner space due to liquid and solids being denser than gasses. Hot air rises and cools, not because of massive energy loss by individual molecules, but because the total number of molecules in any given volume drops with altitude.
The properties of radiative absorbtion in molecules become irrelevant with convection and conduction constantly changing molecular wavelengths through collision.
Willis,
The thing that is most interesting (and surprising) to me is that the assumption of “constant relative humidity” over the ocean appears to be refuted by the data. That is, as you go from the cooler Eastern Pacific to the much warmer (about 5C) Western Pacific, the average relative humidity falls by about 12% (if I am reading the graphs correctly). So instead of a rise in absolute water vapor concentration of ~35-40% across the tropical Pacific, which you would expect at constant relative humidity, the rise in absolute humidity is closer to 23-27%. This really does surprise me.
stevefitzpatrick February 18, 2015 at 5:06 am
When i was a boy in London, on a hot sticky day everyone would say ” what we need now is a nice thunderstorm to cool things down.
And they usually did.
Willis, a fine piece of work and a good learning exercise for me. Looking at any individual buoy, there is an immediate jump in RH right after the sun goes DOWN and the precipitous drop after it rises. I say to myself, well, air cools and then warms and even if moisture were unchanged, RH would go up and back down. This makes sense to me. The real surprise is when you look at the whole string of buoys and see that the warmest part of the ocean has the lower RH. Now that is a revelation in itself as well as an insight into the myopic, simplistic way climate is studied by many of its experts. They go into the office clutching their Clausius-Clapeyrons, instead of going into the field where they will find C-C is of little use in a real dynamic situation where variables not in the equation abound.
Nice one Willis, Thanks. I spent three years in Singapore in the 1960’s and remember the ‘heat and the humidity’. The interesting thing was the maximum daytime temperature never seemed to be much more than 30C all year round, and the night time temperatures never seemed to get cold. I’ve been using that as an explanation for water vapour molecules in the air have a cooling effect when the sun is shinning and a blanket effect (slow temperature drop) at night. Why people think more water vapour will make things hotter beats me. I’ve experience this ‘blanket effect’ from low cloud where I now live in south Wales.
We spent quite awhile over the years anchored in Singapore, anchored off the Police station on the Malay side at Johor. Convenient place to bring the dinghy ashore, and for security nothing beats anchoring at a police station. Absolutely necessary in the more remote areas where security can be a serious problem. When you come ashore strike up a conversation with the duty watch, asking permission, and you are good to go.
I always thought of clouds as my friends in SE Asia. During the day the sun can be brutal, especially if you have fair skin and are prone to sunburn. Clouds are most common in summer, in the rainy season, where they take the heat off the day. Winter in the tropics is the dry season, where sunburn can be a real problem. Spring and fall are by far the hottest part of the year, where winds are often light during the switch between the on-shore and off-shore monsoon.
ps: the reason you ask the duty watch permission is not to get permission, because it is always granted. it is to show respect so that they will take an interest in your boat and watch it while you are away. same reason you ask the toughs on the beach if it is OK to leave your dinghy. otherwise, it might go missing if you slink past without talking to the locals.
Water evaporates into air because the air is drier, not necessarily because it is warmer. Warm air will hold more water vapor, but it is relative humidity that drives the evaporation, not temperature.
Quite so.
It is the low RH of adiabatically warmed descending dry air that determines how much evaporation there can be.
The amount of evaporation is therefore related to the height from which the descending air column has fallen and that is dependent on the power of the earlier uplift.
A more powerful uplift results in more warming on the descent and thus a lower RH when the descending air returns to the surface.
Global evaporation is controlled by adiabatic uplift and descent via changing RH levels as much as by surface temperature.
If the surface temperature rises then more evaporation occurs but only if RH allows.
Any increase in RH from more evaporation in one location gives more convective uplift because water vapour is lighter than air. The higher extent of the uplift in that location then causes a decrease in RH on the next (longer) descent in another location and so global RH remains stable.
Willis’s thunderstorm / emergent phenomena concept is correct but needs to be scaled to the entire planetary atmosphere rather than just acting in the tropics and the active mechanism is not net radiative fluxes as Willis avers but rather atmospheric mass doing work against gravity (cooling) in uplift and with gravity (warming) in descent.
Willis said:
“But in the much larger area in between the thunderstorms, you have dry descending air. This is air from which the water has been stripped by the thunderstorm through a combination of condensation and freezing.”
For the global atmosphere as a whole there is as much descending air as there is ascending air and the descending air warms adiabatically at the dry adiabatic lapse rate (DALR) as it descends. That is not deniable.
It is that warming of descending air that keeps the surface warmer than it otherwise would be without an atmosphere.
Being dry, that warming descending air is clear of cloud and so lets solar energy in, just like a glass greenhouse roof.
That warming, descending air also reduces upward convection from the surface just as a greenhouse roof prevents convection.
The net result is a surface temperature rise above S-B for the planet as a whole.
The greenhouse effect is nothing to do with radiative fluxes. The observed radiative fluxes are a mere consequence of the vertical temperature profile created by adiabatic uplift and descent doing work against or with gravity.
Wills, let’s put some numbers against his argument of “the excess longwave energy emitted ” is the main driver.
So Sublimation of water is 2,830,000 J/kg. http://www.theweatherprediction.com/habyhints2/524/
To evaporate 1 m^3 of water with sea water specific volume @ur momisugly 15 oC at 0.001009 m^3/kg for each m^3 there is an exchange of
=> 2,830,000(J/kg)/0.001009(m^3/kg) = 2,800,000,000 J/m^3
And since most of this energy is taken from the nearby sea water – it will cool
Specific Heat Sea Water = 4,009 J/kg oC 2,830,000/4,009 = 705 or 705 kg by 1- C
60 sec * 60 min * 24 hours * 365.25 days = 31,557,600 sec/yr
Fig 6- Radiative forcing for different anthropogenic and natural perturbations from 2005 relative to 1750. Re-printed from IPCC 2007. http://www.mathaware.org/mam/09/essays/Radiative_balance.pdf
Shows Radiative forcing of CO2 = 1.66 W/m^2 CH4 = 0.48 W/m^2 N2O = 0.16 W/m^2 and Halocarbons = 0.34 W/m^2. Total Long- lived greenhouse gases = 2.64 W/m^2 for their changes from 1750 to 2005.
Joule = Watt * sec
All this leads to => 2.64 W/m^2 * 31,557,600 sec/yr = 83,312,000 J/m^2 in a year.
Compare to => 2,256,600 * 1000/ (J/KJ)/m^3 = 2,256,600,000 J/m^3 to evaporate the water
–> 83,312,000 J/m^2/2,800,000,000 J/m^3 = .03 m = or 3 cm and if open ocean/total area is 65% then 3/ .65 = 4.6 cm (2.54 to the inch) of extra ocean evaporation would eat up all the extra LW radiation from Long-lived GHG from 1750 to 2005 each year.
In comparision the total annual ocean evaporation rate = 140 CM.
from http://www.eolss.net/sample-chapters/c07/e2-02-03-02.pdf
His ideas of the drivers do not add up correctly.
Could you flesh out the logical step between your last two paragraphs a little?
I read your comment to say that the putative forcing increase over the industrial era is enough to support a 3 cm / 140 cm = 2% increase in rain. Presumably such a rain increase would on average reduce the proportion of the (increased) optical thickness that the surface’s heat energy has to traverse to escape to space: the positive-feedback effect of the optical-thickness increase would to some extent be canceled by the negative effect of that optical thickness’s being partially bypassed.
But how does that refute the proposition that “‘the excess longwave energy emitted’ is the main driver.” Driver of what? With what is that 3 cm being compared? How much of that possible rain increase has actually occurred? Quantitatively, what effect would it have if it did?
Thankfully someone else can do math as well. (I’m not being sarcastic) When CAGW makes those kinds of statements that’s the first thing I do, is the math… and that is being generous using their numbers.
GHG (if it works the way they say it does) may not be the only factor warming water. Microwaves at 2054Mhz works really well, decrease the magnetic field a little, and it’s not even affected by cloud cover, zips right through. The really great thing is that the effect at the poles is squared. It can be darn right freezing and still melt ice.
To head off future useless debate by CAGW, they will say that once that heat is released from the latent heat of water vapor, that adds to further warming. Never mind that cooler drier air that gets displaced and pushed down by thunderstorms. (Actually had that conversation that didn’t happen during a thunderstorm) Again the math is pretty easy to do.
The 1% increase in water evaporation is lower than the 3% that I give GHG. Either one, basically background noise.
“The real surprise is when you look at the whole string of buoys and see that the warmest part of the ocean has the lower RH.”
No surprise because the warmest SSTs are beneath cloud free skies where incoming sunlight is strongest. Such cloud free skies are a consequence of air descending from above in regions of higher than average surface pressure (descending air) and that descending air is dry with low RH having both warmed adiabatically and having had its moisture wrung out of it during earlier convective uplift elsewhere in regions of lower than average surface pressure (ascending air). That causes lower RH beneath descending air columns (50% of the atmosphere at any given moment).
It takes time for evaporation from the sea surface to raise RH again and during that time the air circulates towards the nearest lower pressure area where the added water vapour is allowed to cause renewed uplift again (water vapour being lighter than air).
All consistent with Willis’s findings as far as I can see.
So you expect the warmest part of the ocean to remain cloudless and with low RH? I think the point is that this causes a build up of moisture and emergent clouds and thunderstorms. I’ll grant you if you simply heat up air, the RH will go down in the short run – it does in the Sahara, but when there is no shortage of water…It might be my poor description of a dynamic situation in my earlier post, because I thoroughly agree it’s consistent with Willis’s findings.
I would expect the warmest areas to remain cloudless with low RH as long as descending air is dominant.
Any moisture that builds up flows outwards towards areas of lower surface pressure and it is there (where ascending air becomes dominant) that the emergent phenomena described by Willis occur.
The problem is that the maps above show the (high level) cloudiest areas are the warmest.
Figure 8 blows the “super greenhouse” nonsense out the window. If there was a ‘super greenhouse’ effect then RH should be greatest where the water is warmest. Instead we find the opposite is true.
“super greenhouse” = super fail.
Dr Ramanathan says “…a combination of increase in humidity in the entire column and increase in the lapse rate within the lower troposphere.”
If I recall my aviation meteorology lectures from a long time ago, surely the lapse rate decreases with increasing humidity?
I had trouble understanding that part, too. Surely he meant something other than what you and I read that passage to say, but I can’t figure out what that might have been.
For the purposes of discussing the greenhouse effect of water vapor, I do not think that relative humidity is the correct measure, although it is closer to what we feel as mugginess. Wouldn’t the partial pressure of water vapor (or an equivalent, like mass density) be the correct measure? If so, then at noon there are 22g of water vapor per cubic meter of air at 165E, and 18.7g/m3 at 95W. Thus at noon the absolute humidity is higher over the warmer ocean, even when the relative humidity is lower. At 5PM, where the curves separate the most, there is still 22.0g/m3 at 165E, and 18.6g/m3 at 95W. At midnight, it is 22.0g/m3 at 165E and 18.8g/m3 at 95W.
So it seems that the absolute amount of water in the air is essentially constant at a given location on the equator, but higher where it is warmer, making for a “steam engine” that more efficiently pumps heat to the top of the troposphere, and lowering diurnal variation in temperature.
Except that the proponent of AGW would simply point out that constant RH, in conjunction with a positive coefficient of saturation value with temperature, implies increasing mixing ratio or absolute humidity.
Hello Willis
you say:
But according to Figure 8, the relative humidity in the convective zones of the Pacific varies inversely with sea surface temperature. And this is true both for long-term average sea surface temperature, as well as for the daily average temperature variation.
I can’t say that I have any great conclusions from all of this. However, it does appear that the modelers’ claim of strong water vapor feedback rests on the idea that relative humidity stays constant in the face of warming. If these TAO data findings are correct, and if relative humidity more generally is not constant with respect to temperature, it would seem that this would greatly reduce the amount of purported water vapor feedback …
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If in the long-term average sea surface temperatures changes (varies) very little in these convective zones of Pacific how would the variation of relative humidity be significant enough to be considered as other than constant?
If the variation of the average SST very little in the long-term, like from LIA to present, how in the face of a significant warming during all this time, the variation of relative humidity in long-term could be significant enough as to be considered other than a constant?
Probably I got something wrong here and hopefully you may explain it to me if that is not much to ask for.
Please understand I am not trying to imply or claim that the “super greenhouse effect” correct and you wrong, or the other way around.
cheers