I plucked this comment off the Hockey Schtick, as it ties in well with a recent post which generated a lot of comment. That post was looking at back radiation over dry areas. This one looks at the role of water vapour – claimed to be a ‘positive feedback’ by co2 driven global warming theorists.
One version of the “greenhouse effect/water vapor feedback” hypothesis that involves the mid to upper levels of the troposphere and water vapor feedback recognizes that humidity causes a slower lapse rate, which raises the altitude at which the air temperature drops to -18C—the affective radiating temperature of the atmosphere. Some people call this altitude the “top of the atmosphere” (TOA).
This version of the “greenhouse effect” hypothesis then applies the standard lapse rate of 6.8C/km to both the older lower altitude and the newer higher altitude to calculate the projected ground level temperature at the bottom of these two respective atmospheric columns.
To better visualize this version of the “greenhouse effect” hypothesis lets use some actual weather balloon soundings from above Las Vegas (specific humidity = 1.04 g/kg) on a particular day and compare it to weather balloon soundings over Little Rock (specific humidity of 13.83 g/kg) that particular day. These soundings are from http://weather.uwyo.edu/upperair/sounding.html and they were both recorded at 11:00 AM, June 1, 2011.
As expected, because of Little Rock’s extra humidity the TOA over Little Rock (6961m) was higher than the TOA over Las Vegas (6806). When I applied the standard lapse rate of 6.8 °C/km to the TOA altitudes in both locations to calculate the “expected” temperature at 750m (the altitude in Las Vegas) I came up with the following numbers:
Las Vegas = 23.3 °C @ 757m
Little Rock = 23.9 °C @ 743m
Had I stopped right here I could have asserted that the extra humidity in Little Rock is estimated to create a +0.6°C positive feedback. But I didn’t stop there. I looked at the actual temperatures at around 750m (the altitude of Las Vegas) and this is what I saw:
Las Vegas = 30.4 °C @ 757m
Little Rock = 24.4 °C @ 743m
As you can see, the extra humidity in the atmospheric column over Little Rock actually created a -6 °C negative feedback! So, even though the TOA above Little Rock was higher in altitude the ground level temperature was lower by 6 °C.
Can anyone guess why the “greenhouse effect” hypothesis predicted a positive water vapor feedback when in reality the humidity in Little Rock created a strong negative feedback?
That’s right! When I applied the standard lapse rate of 6.8 °C/1,000m to the TOA of the dry column of air over Las Vegas it greatly underestimated the ground temperature under that dry atmospheric column. This made the estimated temperature under the moist atmospheric column in Little Rock appear higher than the ground level temperature under the arid atmospheric column in Las Vegas, which is a complete reverse of realtiy.
Again, these figures . . .
Las Vegas = 30.4 °C @ 757m
Little Rock = 24.4 °C @ 743m
. . . are actual temperatures taken on the same day that shows the actual affect of the extra humidity in Little Rock on ground level temperatures, which was a -6 °C negative feedback. This echoes the observations made in the video. If you are curious the actual lapse rate to the TOA over Little Rock was 6.9 °C/km while the actual lapse rate to the TOA over Las Vegas was 8 °C/km.
One final thought, the “greenhouse effect” hypothesis is based upon Joseph Fourier’s calculations that asserts that the surface of the earth is too warm by about 33°C and that water vapor itself (depending upon the author) creates about 20°C of warming. Regardless of how sophisticated the hypothesis, how massive the computer models, how voluminous the peer-reviewed literature, if water vapor can (and has) been demonstrated to be associated with ground level cooling instead of warming then something is askew with that hypothesis.
Hockey Schtick owner Michael S responded:
Thank you Carl for these observations and I fully agree with your salient points. The field of climate science should heed the words of the late great physicist Richard Feynman:
“It doesn’t matter how beautiful your theory is, it doesn’t matter how smart you are. If it doesn’t agree with experiment, it’s wrong.”
Climate scientists, unlike any other field of science I have ever studied, insist their models are correct and it’s the DATA that is wrong!
A particularly striking illustration of the value of my personal guideline:
If AGW theory and its purveyors assert it, assume the 180° converse.
Climate scientists, unlike any other field of science I have ever studied, insist their models are correct and it’s the DATA that is wrong!
However, when the data is cherry picked, adjusted and “tricked” it becomes right!
The 33 K assumption is out by a factor of ~3.7 because ~24 K is lapse rate warming. As for the -18 °C composite emitter, here all bets are off. It’s because standard atmospheric physics which assumes the Schwarzchild Equation is plain wrong. It’s because it creates the wrong boundary radiation condition at the Earth’s surface.
James Lovelock recently bemoaned the fact that we don’t know what the climate is doing when he thought we did 20 years ago. As a result it led to alarmism, including his own book. The problem is that Houghton assumed ‘Local Thermodynamic Equilibrium’ meant the lower atmosphere acts as a black body radiator when there is no connection between statistics of molecules and quantised radiation.
This apparently led to the false claim that the Earth emits as a black body in a vacuum and receives radiation from a black body atmosphere. No engineer/experimental physicist accepts this as valid. The climate people failed to understand that the radiation they measure with a pyrgeometer is an artefact of the shield behind the detector needed to reveal the temperature signal. Thus they mix up temperature and energy to make a Perpetual Motion Machine. The vastly increased warming is supposedly offset by double real low level cloud ‘optical depth’ and a variable pollution effect with the wrong sign, ultimately the same erroneous radiation physics.
So, no climate model can predict climate. They have to change the physics and accept net CO2-AGW has been grossly exaggerated. Their most egregious sin is to have forgotten the main axiom of statistical thermodynamics, Gibbs’ principle of Indistinguishability, in reality molecules have no memory.
What’s real? Firstly, the assumption of 100% direct thermalisation assumes Tyndall and the PET bottle experiments have been interpreted correctly. They haven’t. Some temperature rise at constant volume is adiabatic delta T which you can prove by slackening the cap, delta T falls. Then you have pseudo-scattering’ followed by indirect thermalisation at the walls. You prove this [warning, tentative at the moment] by using a thin walled container – Nahle used a Mylar balloon, and noticed no measurable temperature rise with an optical pyrometer. I wish he had used a direct reading thermometer. Then there is the strongly temperature dependent absorptivity of CO2.
Pseudo-scattering is defined as the almost instantaneous emission in a random direction of a photon of the same energy as an absorbed IR photon by a molecule which has already been thermally excited [about 5% of CO2 at RT]. This restores LTE so no temperature rise.
The process occurs throughout the atmosphere with thermalisation at heterogeneous interfaces, just like the brass tube [Tyndall] or the PET bottle. The rest of the photons escape to space. As for the thermalisation, the warming, mainly at clouds, produces grey body radiation. What you see from the clear atmosphere is the purely spectral thermal emission from the GHGs convolved with optical depth.
The problem with this perfectly logical model is that whilst it is consistent with much lower present GHG warming than 33 K, it throws out the window the most cherished imaginary possession of the climate modellers, ‘back radiation’ and the assumption that the Earth emits as a black body in a vacuum. These are totally fallacious but without them the whole climate change scam industry collapses, so these people are busily preventing publication. Hard luck, the message is spreading quite well by other means.
A further issue is that because the two-stream radiation models are wrong, you only have net radiation flow, hotter to colder, you don’t have as TB has considered 200 W/m^2 to space at the TOA plus the 40 W/m^ through the thermal window, and 240 W/m^ downwards, presumably why the modellers assume bb in a vacuum for the Earth’s surface emission. Instead, the whole atmosphere acts as an emitter up and down but the latter can do no thermodynamic work.
This bit needs some more thinking. Houghton correctly points out that LTE does not apply at low pressures/temperatures. My tentative view is that there will be too few excited molecules/unit volume than are needed to make pseudo-scattering dominant. In radiation terms,Kirchhoff’s law of Radiation might not apply. I am also looking closely at Hottell’s work in this area.
Yes, water vapour actually has its greatest cooling effect during daylight hours because it absorbs incident solar radiation as shown in the graphic on this page.
At night it will not significantly slow the rate of cooling of the surface, but it will keep the ground level atmosphere a little closer to the temperature of the surface, so the temperature gap of, say 2 degrees may be reduced to one degree, for example. This affects measurements of temperatures by weather stations, but not the temperature of the ground under your feet, or, more importantly, the ocean temperature.
Radiation from the atmosphere can only reduce that component of surface cooling which is by radiation. It cannot have any effect on the other two thirds of surface cooling which is by non-radiative processes. These other processes will tend to speed up if radiative cooling slows, thus compensating and leading to no net effect on the overall rate of surface cooling. Of course the IPCC neglects looking into this.
You can see what happens to low frequency radiation (such as that from the atmosphere) by experimenting with your microwave oven. Pour two glasses of water into a microwave bowl and tape an identical one upside down above it, so that no radiation strikes the water directly. Refill the glasses and also place them in the MW oven like this.
The low frequency radiation is scattered randomly by the molecules in the plastic without any of them getting warmed. About half the radiation gets through and then warms the water just as much in fact as the water in the glasses. (The water is not warmed by the normal atomic absorption process, only by whole molecules rotating in resonance and developing frictional heating.) So too does radiation from the atmosphere get scattered by the surface without transferring any heat at all to the warmer surface.
Some of these issues discussed here:
http://climaterealists.com/index.php?id=9206
Stephen: I’m being much more radical in my thinking in considering the GHG molecules as an energy transfer medium operating at near the speed of light both to and from clouds, including over the horizon.
In contrast, the climate models use the Schwarzchilld two-stream idea [as does Sagan's aerosol physics] to look solely at what is vertically above the Earth’s surface.
In essence, I am trying to flesh out Miskolczi’s hypothesis. And in common with Cotton and Johnson I am also trying to extend Planck but in my case by establishing a radiative control system based on inputs and outputs of the quantum density of states between kinetic and radiative energy.
The understanding of the S-B equation by most present day scientists is pretty poor because they fail to appreciate how it was derived and how the emissivity and absorptivity can vary considerably when you get a significant deviation from LTE.
The key point, as highlighted in the article, is that the net effect of water (vapour, clouds etc.) must be a negative feedback to any change in forcing (CO2 or Solar). If instead we suppose net feedback is positive (as does IPCC) then the oceans would have long ago boiled away as the sun’s output slowly increased 30% over the last 3.5 billion years. The faint sun paradox can only be explained with negative feedbacks. CO2 alone cannot do it and recent geological evidence effectively rules out massive CO2 or Methane dominated atmospheres.
I have also made 2 related studies comparing averaged temperatures for arid desert regions with those from fully humid regions. In both cases the deserts warm (and cool) significantly more than the humid regions graph here. Water vapour dampens the temperature response rather than amplifies it. Oceans act to self regulate the Earth’s temperature.
What we learn from Planck is that no solid, liquid or gas can radiate spontaneously at higher intensity at any frequency. So, if you imagine the Planck curve for a typical mid-troposphere temperature, the spectral lines for CO2 will be mostly toward the sides of the distribution, not at its peak. This calculator shows that the main 15 micron radiation for CO2 would peak at very close to -80 deg.C, which is found only in the upper mesosphere.
The pseudo scattering (“resonant scattering” in my paper) mentioned by Mydog in this post uses up some of the radiating capacity of a warmer target such as the Earth’s surface. So, when we observe similar radiation coming back out of a (near) blackbody, much of it is merely pseudo scattered incident radiation. I postulate that some radiation is scattered by the cooler body and all by the warmer body. The amount of scattering in each is represented by the area under the Planck curve for the cooler body, simply because each body is capable of radiating these frequencies at the indicated intensities. Heat transfer is represented by the additional area between the Planck curves, as science has always said when it calculates the difference between the two areas in order to then quantify heat transfer. This is how nature ensures heat flow is always from hot to cold regardless of any radiation or other heat transfers in the other direction.
The importance of this is absolutely crucial to understanding atmospheric physics. The surface cannot receive any heat transfer from cooler parts of the atmosphere. But such backradiation does slow down the radiative component of surface cooling because it supplies electromagnetic energy (not thermal energy) which the surface uses immediately for some of its quota of radiation. So the surface does not need its own thermal energy, and so radiative cooling is slowed down.
But note that there is no energy transfer from the surface to the atmosphere which is caused by any of this backradiation. Hence we should not count that component of upwelling radiation at all when determining how the surface is cooling. This leaves sensible heat transfer playing a much larger percentage role in surface cooling, and it cannot be slowed by backradiation because the energy in the backradiation was not converted to thermal energy. So there is no subsequent heat transfer to other bodies on the surface which might then cool by other processes. Backradiation can play no part in any of this.
The energy in the original surface radiation (due to solar warming of the surface) is distributed through most altitudes at least to some extent. Hence the first two metres gets a very small share of energy from the surface by way of radiation. This makes sense, because it means sensible heat transfer plays by far the major role in keeping the air we breathe (and measure in weather stations) close to the surface temperature. Radiation could never do this because the vast majority of its energy is absorbed at higher levels or gets through the window to space.
Finally, carbon dioxide is of course not a blackbody, and its few spectral lines (below maximum intensity as explained above) will not radiate very much, and so carbon dioxide molecules will each have far less effect than water vapour molecules, which do have more frequency bands. In fact, if water vapour is already radiating in a band which envelopes a carbon dioxide spectral line, then that CO2 radiation can have no additional effect anyway, because total emission for any small volume of air is still limited by the Planck curve, and water vapour is already using up the quota.
So, where does all the above leave carbon dioxide? It can only play a very small role (probably less than 1% of what all the water vapour does) in slowing only the radiative cooling component of the surface. But this component is less than shown in energy diagrams because all the scattered backradiation should not be counted when it comes back out of the surface, because it is not transferring heat from the surface. Furthermore, in so far as climate is determined by measurements between 1.5 and 2m above the ground, that small amount of radiation originating from the surface nearly all passes through those 2 metres anyway. And if the surface cools more slowly by radiation, what is to stop compensating acceleration of cooling by non-radiative processes?
Doug,
most of what you have written above seems to be based upon the assumption that the ground is always warmer than the first 2m of air above it.
That may be the case in the places like the Australian Outback during the day, but over most of the globe, 24/7/365, it is not.
Therefore the atmosphere is not heated bottom up by the Earths surface, as you continue to imply with your back-radiation arguments.
There is a temperature inversion at around 4′ down to the ground over most of the Earths surface. Which is why Stevenson Screens are placed at that height.
The difference between the air temperature at 4′ and 4” above the ground can be as much as 5-7º on a sunny day in spring, here in the UK. The ground will be even colder still. This is one of the reasons for the invention of such things as shoes, socks and chairs for example.
This air temperature inversion in the first 4-5′ above the ground can mean only one thing Doug, that the air is not being heated by the ground but directly from above by the Sun.
This exposes the back-radiation argument for what it is, a red-herring.
Will says:
May 17, 2012 at 11:21 am
The difference between the air temperature at 4′ and 4” above the ground can be as much as 5-7º on a sunny day in spring, here in the UK. The ground will be even colder still. This is one of the reasons for the invention of such things as shoes, socks and chairs for example.
Yes, Will, common sense really. And because of the low thermal capacity of the atmosphere, compared to oceans and land mass, it make one wonder why the CAGW cabal think air temperature is such an important indicator of climate. The dynamic oscillating balance of thermal energy in and out is the important climate metric – average global air temperature is meaningless.
Tenuc: the temperature inversion mentioned by Will is misleading because in the morning, the ground is cold yet the air arriving from the East where the sun has been heating the ground and expanding the air above it for many hours, is warmer.
I notice this every spring when I cycle East: in a period of high pressure. the wind/breeze in my face is cold but the ground is colder. What you are measuring is the convective boundary layer.
“… which raises the altitude at which the air temperature drops to -18C—the affective radiating temperature of the atmosphere. Some people call this altitude the “top of the atmosphere” (TOA)…”
This is not how I have ever seen “top of atmosphere” defined. The TOA is not a middle layer at some middle temperature (-18 C = 255 K), but the top radiating layer (typically radiating at the coldest temperature).
* on average, the surface temperature (~ 15 C = 288 K) will be ABOVE the effective temperature (-18 C = 255 K).
*on average, the “TOA” temperature for CO2 radiating to space ( ~ -55C ~ 220K) will be BELOW the effective temperature (-18 C = 255 K).
Look at http://acmg.seas.harvard.edu/people/faculty/djj/book/bookchap7-15.gif The resolution is a little low, but the big “bite” out of the spectrum near 600 cm^-1 = 15 um is clearly down near 220 K.
(You could say that the “TOA” is different for different wavelengths. In this particular IR spectrum,
* the “H2O TOA” is about 260 K
* the “CO2 TOA” is about 220 K
* the “O3 TOA” is about 280 K)
For every other wavelength, the “TOA” is the surface, at 320 K)
“This version of the “greenhouse effect” hypothesis then applies the standard lapse rate of 6.8C/km to both the older lower altitude and the newer higher altitude to calculate the projected ground level temperature at the bottom of these two respective atmospheric columns.”
I wouldn’t say that either. The ground temperature is determined from measurements (eg surface weather stations or satellite IR spectra). The TOA temperature is similarly determined (using satellite IR measurements).
The lapse rate is a bit of a constraint on the altitudes where these TOA’s can occur, but the lapse rate is not used actually calculate the ground temperature in any model I know of.
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If that was indeed the “greenhouse effect hypothesis” you want to critique, you are critiquing a strawman. I have seen descriptions trying to make this sort of argument (eg Postma’s work), but (IMHO) they are wrong. In fact, I now think you are actually critiquing Postma’s alternate approach, not the more standard approaches taken by others in climate science.
I am working on my own explanation of the GHE. Maybe I can finish that so that you can see (at least my interpretation of) a proper explanation of the relationships between GHGs, lapse rate, and TOA.
MyDog,
Your implication that the ground heats the air is the only thing that is misleading.
The ground does not heat the air, the air heated directly by the Sun. I have spent three years collecting multiple forms of evidence for this and this evidence speaks for itself.
The assertion of bottom up atmospheric waring from the ground, the corner stone of the ‘greenhouse effect’ hypothesis, is fallacious nonsense.
The atmosphere is directly heated from above by the Sun.
Hi Will: The ‘official estimate’ is that ~16% of the Sun’s energy is directly absorbed in the atmosphere. There is evidence this is an underestimate. Clouds absorb around 30W/m^2 more than theory indicates they should.
On the other hand, there is no doubt that quite a lot of the Sun’s energy makes it through the atmosphere, and several metres of water, and warms the dark peaty beds of still lakes. The convection set up in the overlying water is easily measurable.
So what is your estimate of the relative amounts of the Sun’s energy absorbed by atmosphere and surface?
Cheers
Rog
Will says:
May 18, 2012 at 4:15 pm
“Your implication that the ground heats the air is the only thing that is misleading.
The ground does not heat the air, the air heated directly by the Sun.”
Measure the temperature of the air over a dark surface (like asphalt or a dark roof). Go to a nearby lighter surface (like a grassy field of a light roof) and measure the air temperature. The air is not different a 100 m away, but the air temperature will be. The only difference is the surface of the earth. Therefore the difference in temperature is due to the surface. Therefore the surface of the earth — at least to some extent — does warm the air.
Roger,
Extinction is actually said to be 25%. TSI at TOA is 1364 W/m2 or so and the max at sea level on a clear day is 1000 W/m2, which is close enough for me.
I have shown you previously, using the radiosonde data, exactly how to determine which parts of the Earths solid surface are actually warmer than the air above. If you bothered to look into it you would know how insignificant bottom up warming actually is.
The temperature inversion in the first 4′ above the ground is confirmation of this information I shared with you previously.
The whole TOA concept is very, very tenuous.
Exospheric hydrogen [Geocorona] has been observed 100,000 km from Earth.
No doubt this hydrogen has cooled during its 100,000 km journey from Earth.
Theoretically, the Geocorcona extends out to about 200,000 km.
So, arguably, the TOA is [roughly] at an altitude of 200,000 km.
Beyond that distance the hydrogen [and any heat] can be deemed “lost to space”.
Therefore, any “energy budget” for the Earth has to address this 400,000 km diameter atmospheric “heat diffuser” that surrounds the 12,742 km diameter terrestrial “heating element” we call planet Earth [ignoring the Earth's extended "magnetotail" of at least 200 Earth radii].
tjfolkerts,
A stretch of tarmac here, a brick wall in direct sunlight there, is not going to evenly heat the entire atmosphere throughout each day is it.
Tallbloke says: “The ‘official estimate’ is that ~16% of the Sun’s energy is directly absorbed in the atmosphere.”
Will says: “Extinction is actually said to be 25%. ”
You are both partially right, but you are also both addressing slightly different topics. Light can be either absorbed by the atmosphere OR scattered (leading to the blue color).
>> 78/341 = 23% gets absorbed (using Trenberth numbers).
>> This is noticeably higher than Tallbloke’s estimate.
>> a few more % gets scattered even by “clear” skies
Combining these two would lead to the total 1 – 1000/1364 = 27% attenuation.
Will says: “A stretch of tarmac here, a brick wall in direct sunlight there, is not going to evenly heat the entire atmosphere throughout each day is it.”
Ah, but now you are adding two extra stipulations.
1) Small patches will not lead to large heating, but the sum-total heating will be significant. The WHOLE SURFACE is absorbing energy. Even the grass can contribute to warming the atmosphere (just not as much as the dark rocks).
2) I never said it was evenly heating the entire atmosphere, just that it was a least a component of the heating. The heating would be concentrated in the lower layers.
You can debate the particular numbers that Trenberth presents, but ~ 17 W/m^2 of thermals directly heats the atmosphere from the ground. Furthermore, there is a net (396 -333) = ~ 63 W/m^2 of IR from the ground heating the atmosphere. You could also say that the 80 W/m^2 of evaporation heats the atmosphere.
I just can’t see any way to say that the ground is not heating the atmosphere.
Tim Cullen says: “Therefore, any “energy budget” for the Earth has to address this 400,000 km diameter atmospheric “heat diffuser” that surrounds the 12,742 km diameter terrestrial “heating element” we call planet Earth.”
In principle you are right, but it practice most of this is not important. The earth receives energy primarily almost exclusively in the form of sunlight. Yes, there is star light and moonlight, but these are too small to be important.
The earth emits loses energy primarily (almost exclusively) by EM radiation (either reflected sunlight or thermal IR). Yes, there is some UV from this exosphere, but I challenge you to show that it amounts to even 0.001 W/m^2 of cooling. If you can’t show that it is more than 0.1 W/m^2, then it is not big enough to even bother with for global energy budgets.
Will claims the ground level air is mostly heated by the Sun and apparently then warms the surface.
Maybe he should read about some real measurements in peer-reviewed literature, or do some backyard measurements himself both day and night, as I do in Sydney* not “outback Australia.” I didn’t find things much different when I was driving around the UK and Europe a couple of years ago.
If there is no sensible heat transfer from the surface, how come the air is not far colder at night?
* Just now in calm conditions at 8:23am Sat 19 May: Air: 12.7C Ground: 14.4C.
tjfolkerts
I am not actually concerned with what you are saying. I am only concerned with what ‘established science’ says about the so called ‘greenhouse effect’.
And for your information, grass that heats the air is actually called sand, by the way.
Doug,
you put words in my mouth, where did I say that the air heats the surface?
The Sun heats the atmosphere directly, just as it heats the ground.
I have based all my ‘claims’ on actual measurements and empirical evidence.
Most of your arguments appear to be based on the erroneous assumption that the atmosphere is heated by the surface, it is not. You continue on with your assertion that the ground is always warmer than the air above. I have made an obvious point which shows that to be incorrect.
You are entitled to believe what you like, but the atmosphere is not significantly heated by the ground as is required by the ‘greenhouse effect’ hypothesis.
The temperature inversion at the ground is a global phenomenon. Which is why as I have pointed out, Stevenson screens are placed above 4′.
Only at or near the solar zenith, both in time and location, will the ground become warm enough to heat the air above. This fact can be seen in the radiosonde data.
Back-radiation is a straw-man fallacy.
“the erroneous assumption that the atmosphere is heated by the surface, it is not. ”
Will, how does the sensible heat leaving the surface bypass the air on its way to space? I think maybe misunderstanding arises when people are too categorical with statements.
With different atmospheric conditions, at different altitudes, at different times of day, on different surfaces, the proportionate effectiveness of different energy transfer mechanisms varies.
Globally, the ocean transfers a lot of heat into the air at night, because its surface cools a lot less rapidly than the air, the temperature differential increases, and conduction becomes more effective. You can be comfortable camping on the beach for the night while frost is forming in a valley bottom a few miles inland as cold air rolls down off surrounding hills.
Roger,
“Will, how does the sensible heat leaving the surface bypass the air on its way to space?”
If the temperature of the ground is below the temperature of the air 4′ above, I think you will find that the second law prevents the ground from heating the air.
It’s called entropy Roger.
That is categorical by virtue of the fact that it is a law of thermodynamics.
Also Roger, I live on the South coast and I can tell you now that when camping on a beach at a time of year when there is frost inland, “comfortable” is not a word that will spring to mind.
I have backpacked and camped the length and breadth of Europe for 30 years Will and I know where the air temperatures are warmer, and why. Also, Will, the 4′ inversion is not a permanent feature always and everywhere, and the sun doesn’t shine at night. Also, Will, the ground isn’t the sea, which covers 7/10ths of the Earth’s surface.
The incoming Sunlight warms the ocean after partially warming the atmosphere on its way through. The ocean warms the atmosphere some more as the energy leaves again.
Roger,
the diurnal peak is between 12.00 noon and 2pm. At night because the land has a higher heat capacity than the air, the is cooled by the ground. The best that can be achieved without the Suns energy is equilibrium.
If you want to call that heating, fine. I call it semantics.
When the ocean is warmer than the air you get evaporation. Again sorry no bottom up warming.
I’m off to the beach now to freeze my arse off,
Cheers
Will
On the global average the ocean is ~3C warmer than the air above it.
“When the ocean is warmer than the air you get evaporation.”
And conduction/thermal convection.
Enjoy the walk on the beach, take a woolly and a sou’wester.
tjfolkerts says: May 18, 2012 at 9:30 pm
The earth emits loses energy primarily (almost exclusively) by EM radiation (either reflected sunlight or thermal IR).
Where the notional “top of atmosphere” line is draw is a personal value judgement.
An example is the “Karman line” drawn at 100 kilometres to indicate where the atmosphere becomes too thin for aeronautical purposes.
Regardless of where the “top of atmosphere” line is drawn the “energy budget” has to account for the intrinsic energy acquired and dissipated by particles that physically cross this arbitrary “top of atmosphere” boundary.
Observations of hydrogen at a distance of 100,000 kilometres from Earth indicate that tangible quantities of hydrogen have been liberated from the atmosphere.
The extent of the Earth’s magnetotail also indicates that tangible quantities of particles have been liberated from the atmosphere.
On the one hand: the density of particles in the geocorona is very sparse.
On the other hand: the size of the geocorona is vast compared to the atmosphere.
Quantifying the flow of these energetic atmospheric particles across a notional “top of atmosphere” line is not a simple task. But it is a necessary task to justify the claim that heat is lost almost exclusively by EM radiation and to demonstrate that the “energy budget” accounts for all known inputs and outputs.
The geocorona may well be another elephant sitting in the “energy budget” room.
http://i1222.photobucket.com/albums/dd489/MalagaView/Exosphere.jpg
I challenge you
The falsification of predictions is the final arbiter and a theory is never proved because it may be falsified tomorrow. Therefore, let’s avoid personal rhetoric and simply enjoy contributing to the debate as we watch the scientific process unfold.
“The falsification of predictions is the final arbiter and a theory is never proved because it may be falsified tomorrow. ”
That was my point. I was asking you to falsify the standard hypothesis that “the energy balance of photons between 0.1 um and 400 um arriving from the sun and leaving from the TOA is sufficient to include all important energy flows in/out from the earth.” Falsification is a critical part of science. But conversely, science must keep moving ahead with what it does know. Falsification requires actual work, not merely speculation. If you can provide a number that quantifies an energy loss or gain that is indeed important, then you have falsified the standard hypothesis.
This actually gives two avenues of attack
1) What level is “important”? I would say somewhere around 0.1 W/m^2, since this is significant fraction of the estimated net imbalance. This is also smaller than changes in insolation, so varitations from the sun itself are larger than this. If you think a smaller number like 0.01 W/m^2 is important, then justify that
2) What other energy flows exist that are important. For example, geothermal energy is estimated at ~ 0.1 W/m^2. This is on the edge of being important. If the number is actually 1 W/m^2, then I think it would be important to explicitly include this in the energy balance. If it is as small as 0.01 W/m^2, then it is not worth mentioning.
Is moonlight more than 0.01 W/m^2? No. Even a full moon only has an in’lun’ation” of ~ 0.003 W/m^2.
Is the inflow of energetic particles important? Well, they create the auroras, but those are dimmer than moonlight and concentrated in small areas
Is UV from the outer atmosphere important? I seriously doubt it. The light is primarily scattered Lyman-alpha. This light near 122 nm in the solar spectrum is weak to begin with. The line is narrow, so only a small bit of the weak radiation gets scattered. But go ahead and show that I am wrong.
And remember that when I can pick any arbitrary boundary (like 20 km up from the surface), then only energy flows in and out of that boundary are important. So for instance, the UV from the exosphere to space doesn’t matter of the TOA energy budget, because it does enter or leave this volume.
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PS I just realized I can easily rule out your hypothesis using a diferent approach. 122 nm UV from the geocorona is “UV-C” and would be absorbed above the 20 km level. By definition, this UV then does not enter the TOA and is not counted in TOA energy balance. Even if it WAS a significant light source (which I doubt) it would not matter.
tjfolkerts says: May 19, 2012 at 2:45 pm
My general point is that I believe we have insufficient quantative data upon which a meaningful hypothesis can be established.
The “energy” input and output flows associated with:
a) material that crosses the arbitrary “top of atmosphere” boundary
b) electro-magnetic energy that crosses the arbitrary “top of atmosphere” boundary
c) material that crosses the “bottom of atmosphere” boundary
d) electro-magnetic energy that crosses the “bottom of atmosphere” boundary
e) atmospheric [exothermic and endothermic] chemical reactions/processes
ALL need to be quantified from my perspective.
Unfortunately, I do not have data that quantifies these flows.
Unfortunately, I do not know how these flows can be accurately quantified.
I think all these flows are important and need quantifying.
You are at liberty to think otherwise.
“There is a temperature inversion at around 4′ down to the ground over most of the Earths surface. Which is why Stevenson Screens are placed at that height. The difference between the air temperature at 4′ and 4” above the ground can be as much as 5-7º on a sunny day in spring, here in the UK. The ground will be even colder still.”
A study that I did of near ground (below two meters) temperature inversions demonstrated that such temperature inversions are primarily a nighttime phenomenon. Rarely, if ever, was the cool air next to the ground warmer than the ground itself. That is, even though the temperature of the air at 4” might be cooler than the air at 4’ it doesn’t mean that the ground is even cooler still. The ground itself when the temperature inversion was greatest—just before sunrise—was predictably 4-6 °C warmer than the air at 4″.
If you go back and look at your data sources you will notice that they do not include actual soil temperatures; it is just assumed that the ground is cooler than the air at 4” because the air at 4’ is warmer.
Why might this be so?
1) The ground not only absorbs and converts all more sunlight into heat than does the atmosphere, it is physically connected to a massive heat sink called the earth’s crust and consequently more resistant to cooling than is the atmosphere.
2) Air is “fluid” and cool, dense air is continually sinking to the bottom of the atmosphere 24 hours a day, which creates these near the ground temperature inversions that actually enhance the ability of the ground to cool. Just because the air at 4″ is cooler than the air at 4′ doesn’t mean that the air at 4″ is cooling faster than the air above it. It more likely means that cooler air from aloft has moved to replace the warmer air below.
Carl