Stratopause Emissions

The discussion at WUWT about a non-radiating atmosphere got me thinking about where DOES our atmosphere radiate? I mean, we have all this talk about “CO2 backradiation” and “IR Windows” and such. Can we figure out just where the heat energy really does the “leaving”? And after that, does it point to a potential mechanism? And is that mechanism limited by the “CO2 Absorption”?

The two WUWT threads:

http://wattsupwiththat.com/2011/12/29/unified-theory-of-climate/

http://wattsupwiththat.com/2012/01/13/a-matter-of-some-gravity/

First off, what does the earth look like from deep space. Does it have a lot of complex texture and a lot of notches and windows? Or does it look like your basic ball of dirt and water?

http://iopscience.iop.org/0004-637X/700/2/915/fulltext/

We present two observations each spanning 1 day, taken at gibbous phases of 57° and 77°, respectively. As expected, the time-averaged spectrum of Earth is blue at short wavelengths due to Rayleigh scattering, and gray redward of 600 nm due to reflective clouds. The rotation of the planet leads to diurnal albedo variations of 15%-30%, with the largest relative changes occurring at the reddest wavelengths. To characterize these variations in an unbiased manner, we carry out a principal component analysis of the multi-band light curves; this analysis reveals that 98% of the diurnal color changes of Earth are due to only two dominant eigencolors. We use the time variations of these two eigencolors to construct longitudinal maps of the Earth, treating it as a non-uniform Lambert sphere. We find that the spectral and spatial distributions of the eigencolors correspond to cloud-free continents and oceans despite the fact that our observations were taken on days with typical cloud cover. We also find that the near-infrared wavebands are particularly useful in distinguishing between land and water. Based on this experiment, we conclude that it should be possible to infer the existence of water oceans on exoplanets with time-resolved broadband observations taken by a large space-based coronagraphic telescope.

So from deep space they can make out land and water. The clouds do not confound the image much, despite their large impact on albedo. Notice not much mention made of CO2 absorption bands. When we look at their data, there is some reduction in spectrum but mostly relative to the 300-400 nm area that is normally bright; and not relative to the broad swath up to 1000 nm area to speak of:

EPOXI Sat spectra observations

EPOXI Sat spectra observations

Compare that with the ‘CO2 notch’ at 15000 nm that we are told will hold in all the IR and burn the planet to a cinder:

CO2 and other gas absorption of IR

CO2 and other gas absorption of IR

That graph is from a satellite looking down at Niger at noon per:

http://acmg.seas.harvard.edu/people/faculty/djj/book/bookchap7-15.gif

Figure 7-8 Terrestrial radiation spectrum measured from a satellite over northern Africa (Niger valley) at noon. Blackbody curves for different temperatures are included for comparison. The plot shows radiances as a function of wavenumber (n = 1/l). The radiance is the radiation energy measured by the satellite through a viewing cone normalized to unit solid angle (steradian, abbreviated sr). Radiance and fn are related by a geometric factor. Major atmospheric absorbers are identified. Adapted from Hanel, R.A., et al., J. Geophys. Res., 77, 2629-2641, 1972.

There are big notches for CO2 and Ozone. I note in passing that the Global Warming Hysterics never like to talk about natural variation of ozone with solar cycle changes and how that might matter… vis our present loss of ozone as the sun has gone all sleepy in the UV bands and the stratosphere has gotten cold. Also note that at the 8000-9000 nm band and in the 10000 – 13000 nm band we can see the surface happily dumping loads of heat at 320 K ( about 47 C ) so the CO2 isn’t stopping that hot surface from radiating like crazy… Below 15000 nm, at 18000 nm, we again have increased radiation in longer IR wavelengths.

To me, this just says that at high noon the CO2 is absorbing one heck of a lot of incoming IR and transferring that excess heat via conduction to the other gases in the air. That is, it is stopping some of the IR at 15000 nm from reaching the ground more than it is ‘re-radiating’ it as ‘downwelling IR’. Basically, the solar levels of sunlight are so high that all the OTHER wavelengths look high in comparison AT NOON as they bounce off the dirt, water, and clouds. But as we see from space, the CO2 absorbs some, but does not re-radiate as hot gas.

So, seen from deep space, we look mostly like land and water with a more or less average amount of water vapor in the air, and little to no indication of any odd ‘notches’… What happened to the CO2 effect?

So I was looking at this article, that is mostly just a defense of the AGW thesis vs the “atmospheric pressure did it” thesis:

http://moyhu.blogspot.com/2010/05/greenhouse-effect-and-adiabatic-lapse.html

This post is prompted by recent posts by Steve Goddard on WUWT about the GHE and the lapse rate on Venus. They muddle the effects, in a way that is quite often seen in the blogosphere. The meme is that surface warming is due to the lapse rate and not to the GHE. Often on WUWT this comes down to even more simplified assertions that warming is due to atmospheric pressure.

UPDATE: Discussion below has convinced me that I had this wrong as I first looked at it. (Not that it matters, it mostly had just caused me to find the ‘net flux’ map below that is what I think really matters). So I’m rewriting this section a bit to look at the 15,000 nm notch as largely irrelevant rather than the original stimulus to look for the net flux graph.

Where I ran into this graph. Stare at it for a minute or two. Look particularly at the measured IR Temperature in the strongest “CO2 Notch” at 15000 nm ( 15 micrometres). (The absorption lines below 6000 are off the chart and the 9500 nm area is too little absorption to be of interest). WHY is it lower when looking down from 20 km and higher when looking upward from the ground?

Upward vs Downward IR emissions on earth

Upward vs Downward IR emissions on earth

IF the CO2 in the air both absorbs and emits at the same spectra, if it really IS keeping all the IR in, ought not we see the same IR when we look “down” at that CO2 (since it emits in all directions) as when we look up at it? ( In the 9500 nm area, we do come close, with both up and down looking to be about 240 K -/+ 10 K ).

UPDATE: At this point, where I had been all interested in asking “Where is the radiation coming from?”, I’m going to instead make the point, as comments showed, that the 15,000 nm notch is actually blocking. Frankly, it strengthens the case that CO2 is not relevant, IMHO. SO, OK, the ‘look down’ shows CO2 blocking at high altitude (colder air temps) while the look up shows it blocking at low altitude (hotter air temps). So what happens? The CO2 just radiates around the energy until such time as the CO2 whacks into some other molecule, that then radiates the heat out in one of those OTHER bands that isn’t blocked, OR, drives convection of the troposphere to move water vapor to altitude and dump heat to the stratosphere (where below we will see the ‘net flux’ is fairly smooth).

What we see is that the atmosphere is relatively cold and NOT emitting well in the CO2 15000 nm notch. Not much “downwelling” going on from a poorly emitting gas… It is shown as about 225 K ( subtract 273 so about -48 C ) and you just don’t get a lot of heat off of something at that temperature.

When we look up, we see about 267 K, or just a couple of degrees below zero C. How can this be? (Not a lot of heat sources at a polar ice sheet and not a lot of warm air rising…)

UPDATE: It can be by virtue of the fact that the graph was from summer and relative warmth of 0 C existed near ground level.

How can the “magic gas” radiate more down than it does up?

So the CO2 is blocking IR. Sufficiently that there is no effective communication between those high and low CO2 molecules (or they would approximate as they exchange energy). That implies the heat from the CO2 is leaving via conduction to other gases and surfaces that then radiate, evaporate, or convect.

Look at the height at which the ‘look down’ was done. 20 km. Golly, that is way up there… but not high enough. What we have here is a simple demonstration that the CO2 in the lower atmosphere acts to prevent IR radiation in the lower troposphere (IMHO via conduction to the rest of the air of any absorbed energy), but does nothing to stop radiation at the top of the stratosphere / bottom of the stratopause.

When we look at the temperature profile of the air, we see a cold lower level, and a nice ‘about zero’ layer a bit above 40 km (and above the ‘max ozone’). What this says to me is that we have a very simple existence proof that the CO2 in the troposphere is rather irrelevant. Convection takes the heat right past it, up to that stratosphere level, where it is then radiated at high altitude.

As the stratospheric temperatures go, so goes the earth… and convection sends the heat to the stratosphere / tropopause. The heat then gets globally circulated and mixed as it is transported to the poles and dumped.

http://apollo.lsc.vsc.edu/classes/met130/notes/chapter1/graphics/vert_temp.gif

Profile of air temperature with altitude

Profile of air temperature with altitude

If you would understand the earth’s IR emissions you simply must look at the stratosphere and how heat is transported to it, and by it. Heat accumulating at the equator, being transported via the stratosphere, and dumped to space at the poles.

http://chiefio.wordpress.com/2012/01/15/outgoing-vs-land-vs-water-vapor/

A graph embedded in that article from:

http://www.earthobservatory.nasa.gov/GlobalMaps/

Showing net energy flux. Heat GAIN at the equatorial regions, heat loss at the poles. There has to be transport in between those areas. Air travels TO the equator from the poles in the troposphere, it’s going to be relatively hot equatorial air that rises to the stratosphere and moves to the poles (where it then sinks and causes a lot of very interesting weather effects, including the polar vortex.)

Net Radiative Flux

Net Radiative Flux Oct 2011

Net Radiative Flux Oct 2011

Notice how lacking in any ‘texture’ is this graph. Little evidence for low altitude artifacts. Little impact from storms, land forms, etc. The net flux is largely leaving in a well mixed layer. What might that be? What layer is well mixed circumferentially, but more slowly mixed pole to pole?

This page:

http://www.vets.ucar.edu/vg/StratosphericWinds/index.shtml

has a nice animation of it.

Stratospheric Circulation Simulation

Almost all air enters the stratosphere over the tropics. A slow, mean vertical circulation, called the Brewer-Dobson circulation, lofts air over the tropics from the troposphere into the stratosphere. Air lofted into the stratosphere then moves either to the north or the south where it drops back down to the troposphere, completing the circulation by moving back towards the tropics.

A second, faster, horizontal circulation is active in the stratosphere. This stratospheric circulation moves from east to west around the equator and changes directions to west-to-east towards the poles. The net result is that particles transported out of the tropics may cover the globe in only two months time.

So if you want to know how the earth sends IR to space and what controls our temperatures; look to the stratosphere. At ground level we’re just in the side effect realm. It is only AFTER all the interesting processes have happened that the descended polar air gives us our weather, an artifact that the AGW Global Warming Hysterics call “climate”.

What controls the stratosphere and upper altitude ozone is what controls the heat radiation to space. AFTER that, the decent of that cooled air to ground level, where it is finally below the largely irrelevant CO2 “blanket”, does nothing much of interest to global energy balance; until it has once again returned to the tropics to be lofted back to the stratosphere.

Looking at surface temperatures in the temperate zone is looking at an artifact of stratospheric changes and the CO2 overhead in the troposphere is entirely irrelevant to the process.

Update

The question has been raised if CO2 would not entirely absorb all the infrared in short order, such that it would not be possible to actually detect (or ‘see’ it, as above) the IR of a layer of air some distance away. That CO2 makes the air effectively opaque to IR in the bands where it absorbs. There are two points that make that assertion a bit, er, irrelevant to the ‘seeing’.

First off is the very narrow actual absorption ‘bands’ of CO2. It is in VERY narrow spikes with wide areas of transmission between them. There’s plenty of opportunity for IR to be emitted in bands just a bit each way (via broadening or via other species) and for that IR to propagate to the sensors that formed the broad spectrum plotted above.

IR Spreding and absorption points of chemical species

IR Spreding and absorption points of chemical species

This graph shows the percent transmission of IR in various bands. Notice just how narrow the ‘dips’ labeled CO2 really are. Most of the dips are from water, H2O. Notice that between 2 and 5 micrometres there are plenty of peaks with about 80% or more transmission. Also, remember that we saw in the chart above that past 15 the absorption again drops ( transmission increases in the LW IR band).

The other “minor” point is the existence proof of things that use IR to see, right through that CO2 laden air. From the Wiki:

http://en.wikipedia.org/wiki/Infrared

3-8 µm In guided missile technology the 3-5 µm portion of this band is the atmospheric window in which the homing heads of passive IR ‘heat seeking’ missiles are designed to work, homing on to the Infrared signature of the target aircraft, typically the jet engine exhaust plume
[..]
8–15 µm This is the “thermal imaging” region, in which sensors can obtain a completely passive picture of the outside world based on thermal emissions only and requiring no external light or thermal source such as the sun, moon or infrared illuminator. Forward-looking infrared (FLIR) systems use this area of the spectrum. This region is also called the “thermal infrared.”

While I’m sure all sorts of folks can come up with all sorts of hypothetical, theoretical reasons, and perhaps even models to show that the IR simply MUST be absorbed and can not leave, I think I’ll go with the folks who make missiles and have their lives depending on seeing through that IR band. Well, that, and those gaping holes of 80% transmission… The Abrams Tank has a thermal imaging system and was shooting other tanks at a couple of thousand meters, so I’m pretty sure the thermal band is ‘transparent enough’ for an imager at 20,000 km looking down to see the thermal image of the air below it, and one looking up to see more than a few metres of ground source air. Another analogy: I get sunburns, despite the abysmal UV transparency over at that low nm end of the scale… The Ozone does not absorb it all, nor does the CO2 absorb all the IR.

So while the 15,000 nm notch may well be blocked, there are plenty of adjacent areas where other IR can leave and gas collisions can move the heat to other molecules for radiation, or for convection to where it can be radiated.

The heat leaves, it leaves at altitude, and that is where the stratosphere is warmest and the IR photons have the least obstructed path to space. Most of the heat is delivered to altitude via convection / condensation, and CO2 is largely unimportant.

Subscribe to feed

About these ads

About E.M.Smith

A technical managerial sort interested in things from Stonehenge to computer science. My present "hot buttons' are the mythology of Climate Change and ancient metrology; but things change...
This entry was posted in AGW Science and Background and tagged , , , . Bookmark the permalink.

38 Responses to Stratopause Emissions

  1. adolfogiurfa says:

    Who has stolen the rest of the spectrum? It seems that those who only eat trash food surely emit a lot of IR light (heat) so they believe that is all the spectrum.
    Why is it so, as M.Vukcevic has proven, that “temperatures” variations follow GMF changes.

    Perhaps someone up above put the microwave oven on and we are being defrosted :-), and to explain it we seek a lot of self calming interpretations…while we are being prepared to be eaten!!

  2. Mark Miller says:

    Interesting analysis. I can’t say I understood the data, though the radiative flux chart made more sense to me, based on what you said.

    What came to mind when you were describing heat flow at the tropics is that this matches with what we see in the formation of tropical storms and hurricanes. You can only get those kinds of storms from a massive upwelling of warm air, which occurs in the tropics, that reaches up to the stratosphere, where condensation “tops out.”

    In fact, let me just bounce this idea off you. If the AGW alarmists were correct, and CO2 is as powerful as they say it is in our situation, and only radiates downwards (this brings to mind a “heat sink” model), then we’d expect to see less severe storms, because the CO2 “cap” would “behead” them, removing their heat energy at the troposphere, reradiating it to the surface, thereby stopping the convection these storms need in its tracks. In this theoretical scenario, I imagine we’d get a lot of precipitation, since the moist air would cool dramatically in the troposphere, and condense.

  3. E.M.Smith says:

    @Adolfo:

    My working thesis is that the EMF modulates the Ozone that just happens to be right in that part of the air (stratosphere) that is in control of actual heat leakage.

    Yes, I left empty (as a void) the question of ‘what heats the stratosphere?’, but gave the information ( as a 1 ) of from where the heat leaves… ;-)

    @Mark Miller:

    No worries. It really IS all about the graphs anyway. Heat / IR leaving from the stratosphere in fairly uniform flows, high above the mass of CO2 in the troposphere.

    Per the AGW model: Well, since it’s a bit broken, you can kind of make it dance in whatever way you like… So I could argue that CO2 warming would flatten the heat differential, and take the fuel out of the convection engine… Or you could claim that the CO2 radiated to the earth making it hotter and the water evaporation stronger and MORE heat trapping and …. eventually leading to massive superstorms from all that heat and water. ( The “classical” end of the world scare AGW story…) Personally, I’d lean a bit more toward your model, where as the CO2 warms, the air differential drops and convection slows / stops. “Decapitation”.

    In reality, we find very tall thunderstorms and hurricanes dumping thousands of nuclear bombs worth of heat into the stratosphere, where it circulates over the whole planet in weeks and leaves, net, at the poles, without much of a CO2 involvement at all. Convection moving water for phase change, with plenty of IR radiation from the total mix of IR radiators at the stratopause.

    A minor “dig here” being to list the elements at that layer. IIRC, there’s a fair amount of ozone and N02 (both 3 atom molecules, so ought to have great IR abilities) along with Lord Knows what other species of complex molecules.

    But the graphs basically tell you the temperature and direction of the IR source, and place it at about 0 C and above 20 km. I make that the upper stratosphere.

  4. Serioso says:

    Oh dear! So many mistakes, so little time…

    Let me start with your observation that looking down from space the effective radiation temperature in the 650 cm-1 band is very cold while the looking upward radiation temperature is about the same as the ground temperature. The explanation is exceedingly simple: CO2 absorption is SO strong that hardly any photons in this band make it more than a few meters before they are re-absorbed (and re-emitted).

    There are other errors in you analysis but I am reluctant to point them out unless I can be reassured that you will not damn my posts to moderator hell for what I believe are excessively long periods of time.

    And the thread you cited,

    http://wattsupwiththat.com/2012/01/13/a-matter-of-some-gravity/

    is basically irrefutable. The Elevator Argument by Willis Eschenbach is brilliant.

    [ Serioso, I would strongly suggest dropping some of the sniditude. It is comments like "so many mistakes, so little time" that get folks put into the moderation queue (and that can have comments turned into "carping comments" fodder). But, to your point: I've added a little graph that "zooms in" more on just the IR portion and shows the EXACT spectral lines of CO2 and water. Notice that CO2 lines are the narrow tiny ones. Almost everything else is water. (and some ozone). Notice in particular that the 650 you call out is basically all water. CO2 is that dinky little dip at about 425 and that tiny notch at about 950. At the pole, where that graph was made, there isn't a lot of water vapor left in the air. So that up/ down graph is letting us see pretty easily. Even in places with lots of water vapor (like, oh, jungles) those missiles see through the air pretty well in that part of the spectrum. So I'm pretty sure it's not exactly opaque.

    Per Willis and his toy world argument: Toy worlds can prove nothing. As I said in my comment there: he basically creates an unphysical tautology via defining gas as the functional equal of a vacuum and then finds that gas does nothing. Doesn't prove anything, just makes an interesting word game. They end up being arguments of the form "Given these conclusions what assumptions can I draw?"; so I simply ignore them most of the time. They are the kind of endless "angels and pins" time wasters that consume far too much of peoples lives. Science is based on observations, measurements, data. Philosophy and religion are based on Toy Worlds arguments. They can be helpful in giving you ideas of what to conduct as a test, or what kind of experimental data to gather, but on their own they can prove nothing. So I don't play in Toy World. Sorry. See above for real world data...

    Per "moderator hell" and "what you believe are excessively long periods of time": Not my problem. YOU have control of what you type. Say things like "OH, SO WRONG!!!!", you go into the bit bucket. Say things like "Doesn't the CO2 absorb it all?" then it's a simple conversation point. Say "I think CO2 absorbs it all.", that's a personal assertion of belief; quite fine. It's called "manners". Not tossing rocks at other folks. Not complaints "to the person", but "to the topic". I know, silly me, enforcing such an obsolete thing. But it's who I am. Carping, (aka pissing and moaning and bitching) at me gives me little reason to take time from my coffee, my dinner, or even just watching TV, to 'deal with it'. Folks who can handle that get an open mic. Folks who can't, get scraps of my leftover time (after I've done the important things in my day, like coffee and what happens an hour after coffee). But, as some folks are 'slow learners', let me make it perfectly clear: If the clear tone or intent of the comment is to make me 'feel bad', I have NO need nor desire to facilitate it. If the clear tone or intent of the comment is to learn something, or ask if some point is relevant, well heck, anybody can miss something and that's the whole reason I put "dig here!" all over things. To point out particular bits I already know are not quite filled out. So if you can "collaborate to further understanding", well great! If you can complain and insult, well, I've got relatives for that ;-) and don't need more. -E.M.Smith ]

  5. kuhnkat says:

    EM,

    You got me confused. When you are talking about the 500-700 notch that is referring to Wavenumber on the IR Figures. Yet, you say that is 500-700 Nanometers which is on the Epoxi charts. HELP!!!!

  6. E.M.Smith says:

    @Kuhnkat:

    I’ve probably managed to get um, nm and wavenumber jumbled. I’ll go back and see if I can make it more uniform.

    UPDATE: OK, I’ve put nm markers next to things and tried to clarify which thing I’m talking about where. Hope that helps.

  7. George says:

    Any greenhouse must have a “lid” that acts as a barrier to convection. That lid on our planet is the tropopause. That is the “roof” of the greenhouse. Now, your average greenhouse works by allowing in the visible which gets turned into heat and by blocking the infrared from escaping the system.

    In our planet the CO2 in the troposphere doesn’t matter because we have a refrigeration system that bypasses it. When you have a large cloud that rises to the tropopause and spreads out (those big “anvil” shaped thunder heads) it is radiating its energy from the tropopause. The water evaporated at the surface, rose up and released its energy at altitude bypassing most of the CO2 in the atmosphere.

    The only thing that matters is how much LWIR gets trapped in the stratosphere. The majority of the heating of the stratosphere is due to solar UV radiation. That is why the temperature of that portion of the atmosphere increases as you rise in altitude. Sure, there might be some change in stratospheric temperatures due to changes in CO2, but the thing is the variation in solar UV is so great, that it will swamp any tiny change in temperature due to CO2. In fact, CO2 may act as an atmospheric coolant at that altitude. If the stratosphere cools, then the atmosphere below it will cool, too. But, as luck would have it, CO2 absorbs UV, too. So again the UV variability might be swamping any LWIR heating by quite a bit.

    http://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.167.1163&rep=rep1&type=pdf

  8. E.M.Smith says:

    @George:

    Look at the video in the link of stratospheric circulation. Yes, clouds and convection run into the tropopause, but that heat dumped doesn’t stop there. It enters a very mobile stratosphere that has some pretty fast circulation in it. ( I agree with all the rest of your comment – just making the point that the stratosphere is not a quiet static place devoid of heat flows and mass flows…)

    I think it also matters that there are other 3 atom molecules formed in the stratosphere. They all ought to pick up that tropospheric convective heat and help dump it it as IR. IMHO, that explains the ‘well distributed’ and smooth nature of the net flux graph. It’s all the mixing of the convection followed by the stratospheric mixing smoothing out the radiative surface.

    It’s all just a couple of giant heat engines working on mass flow to take the absorbed light and dump the heat to altitude and move it to the poles where it can be radiated away.

  9. Nick Stokes says:

    “When we look up, we see about 267 K, or just a couple of degrees below zero C. How can this be? (Not a lot of heat sources at a polar ice sheet and not a lot of warm air rising…)

    How can the “magic gas” radiate more down than it does up?”

    The answer is that it isn’t the same gas that you’re seeing. At 15 micron, CO2 enits and absorbs; the air is fairly opaque. When you look up from ground, you see emission from near ground level. In the Arctic plot, that was in summer, and the air temp is about 267 °K. But when you look down from 20km, you see emission from the tropopause, at about 225 °K.

    The “warm” air near ground is emitting upward, too, at 15 micron. But that doesn’t get far.

    Conversely, in the atmospheric window at about 12 micron, the air is transparent. From below, you see space – nothing at all. And from above you see the ice at about 267 °K.

  10. E.M.Smith says:

    @Nick Stokes:

    I looked all over for some seasonal indication for that graph and couldn’t find it. Where did you get the summer date?

    ( I was willing to ‘go with it’ based on ‘over ice sheet’ as likely meaning non-summer. Then again, it is Alaska ;-)

  11. Nick Stokes says:

    I have a memory that it was August, but I can’t now find the source for that. However, you can read from the graph that the AW (8-12 micron) temp looking down is about 267K, as is the air temp at 15 micron looking up.

  12. wayne says:

    Excellent EM, as usual. Didn’t mean to just vanish after Christmas but still time bound writing numberic integrations related to N&T. I’ll be back to read this in more detail.

    Two curious points. Co2 lacks a permanent magnetic dipole so it can’t hold onto it’s absorbed energy. And two, after reading in Petty’s book on radiation that 95% of surface radiation in co2’s lines is absorbed and constantly reemissions in the first meter, ~99% in the first 5 meters, then it all starts to make some sense. Seems we’ve been sold a bill of goods of co2’s high in the troposphere beaming back to the surface, doesn’t happen.

  13. Pascvaks says:

    If the world would just stop for a day or two I think I might be able to figure out what’s happening. You know, get a better picture or all the comings and goings without pulling my hair out;-)

    Anywho, came across a piece with a pic I just had to pass on. The piece –

    http://www-das.uwyo.edu/~geerts/cwx/notes/chap01/tropo.html

    The height of the tropopause
    B. Geerts and E. Linacre (11/’97)

    The Pic –

    Stratospheric / Tropospheric Mixing

    ___

    Does anyone else get the funny feeling that planets like Earth have little “Coronas” like stars? Real little;-)

  14. P.G. Sharrow says:

    @Pascvaks; not funny, real. Just different energy levels. GOD works under simple rules. Men make things way too complicated. K.I.S.S. method. pg

  15. Serioso says:

    Please note that Nick Stokes is saying the same thing I said: CO2 absorption in the 15 micron band is SO strong that, looking up, one sees radiation originating close to the ground, while looking down from space one sees radiation from high up in the atmosphere. Wayne makes a similar point from Perry’s book about the intensity of the CO2 band (although he confuses electric dipole with magnetic dipole).

    You say “CO2 is that dinky little dip at about 425 and that tiny notch at about 950″ Let me try to be polite about this: Your statement is exceedingly misleading. Note the transmission goes to zero at wavelengths above 14 microns. Zero! This is CO2.And this band is right in the middle of earthshine emission.

    And, as for characterizing Willis’ argument as describing a “Toy World,” you are right. But both the real world and the toy world have to obey the First Law of Thermodynamics, and, as Willis shows, descriptions of the real world that ignore the effects of long-wave radiation violate basic physics. His argument should not be casually dismissed just because it is a simplification.

    [ Look, it's the sniditude of things like "let me try to be polite about" that sets you apart. Nick added some useful information: That the graph may have been made in August. One of my "wait a minute" moments about the graph was that it was 'over the ice sheet' in Alaska. Now most of the time that's well below zero C. BUT, if the graph was made in August, it will be 'about C'. I looked for a date reference, but couldn't find one. Nick is reasonably polite about things and provided that information - along with the standard view that IR will be blocked. You provided snippyness and complaints.

    You have ended up in the Moderation Queue after a lot of such events, not just any one. Nick has an open mic after many clear and evidence based comments, speaking 'to the topic' not 'to the person'.

    Moving on to the "try to be polite" point. Let ME "try to be polite" about this: The statement about the little notches was about the little notches, not the 1500 nm point. Do try to read what I say and not what you would like to see. Per the 1500 nm point. Yes, I saw it go 'to zero', but look up the page and you see another chart where it does not go to zero. Which is right? Which is a scaling artifact? An interpretation issue? HOW FAR is it through air to zero? Is "almost zero" really enough to stop heat from leaving? Is a zero (or near zero) at 1500 nm enough to prevent the heat from jostling a molecule (or a momentarily formed composite of molecules) sufficiently to let the heat out just a smidge over on the range? And about that 'past 1500 nm' area where emissivity rises again... So, you see, to point out the 'little notches' is to point out the areas where IR is moving Just Fine and they ARE CO2 notches. To fixate on 1500 nm is to ignore that it curves down into that point and rises out of it (and the bottom is ill defined per the difference between the two graphs).

    Could it 'be zero' (real, absolute zero) transmissivity? I suppose so. But I suspect the reality is more of a 'reduced a lot but not absolute zero'. Further, there is the question of when IR is absorbed and re-emitted, is it not also re-emitted both up and down? Does not that IR going up, even if again absorbed, get again re-emitted? How fast does this propagation move? So even if an instrument "sees" an instantaneous state, does it say anything about propagation? So, IMHO, there are a lot more questions to be answered here than just pointing at a graph and saying "It is zero!!!!!".

    Now, just to be very clear so you can grasp this: Saying that I'm being "misleading" is a statement to ME and to MY INTENT. Two things you simply can never know. Further, it is colored with innuendo of a negative motivation. It is exactly that sort of thing that gets YOU the slow boat and Nick the open Mic. I have great patience, but it is not unlimited. Keep up that sort of snide attitude and you will just end up in the bit bucket.

    You can go back to playing with your Toy Worlds now... -E.M.Smith ]

  16. adolfogiurfa says:

    @Pascvacks: Does anyone else get the funny feeling that planets like Earth have little “Coronas” like stars?
    That´s real! and earth´s corona temperature=1500ºC. We are evolving…a little.
    Have you seen my http://www.giurfa.com/unified_field.xlsx
    There you will find the Sun´s core diameter, of course smaller than the earth because of its higher frequency/energy.

  17. P.G. Sharrow says:

    @Adolfo; interesting you quote 1,500C for earth’s high corona.
    O2,N2,O3.N3 and NOx all radicalize around 1,000C and become stable below that. As they loose energy and get cold O3,N3 and NOx break down to O2 and N2. Radicalized oxygen and nitrogen gain and loose energy as if they are catalyzing each other to form long strings of NOX as well as clouds of O3. This has been known to those of us that deal with surface pollution control for a very long time. Climate science has not learned this yet. pg

  18. kuhnkat says:

    Nick,

    glad you showed up. How do they tell what temperature the radiation is coming from. CO2 and the other GHG’s mostly emit in specific bands based on their molecular structure not on their temperature. How does this work that they can just say it comes from a particular temperature level?!?!?!

  19. Nick Stokes says:

    KK,
    you tell from the dashed BB curves. Emission is banded, but the BB curve is the upper limit at the temperature marked. You can see that large parts of the spectrum track (and do not exceed) one of those BB curves; the curve gives the temperature. In the Arctic looking down plot, you see a section tracking 267K and another tracking 225K.

  20. Curt says:

    EM — there’s a math mistake in your post that definitely affects your arguments. 15 micrometers is equivalent to 15,000 nanometers, not 1500.

  21. Serioso says:

    @kuhnkat

    To amplify Nick’s reply: A measurement is made as to the absolute intensity of the radiation at a particular wavelength. The measured result is then compared to the theoretical blackbody radiation intensity at the same wavelength. Since the calculated intensity is a function of temperature it follows that a measurement of intensity is a measurement of temperature.

  22. gallopingcamel says:

    Curt is right. The big CO2 “notch” is at 15 microns and that is close to the maximum for the radiation spectrum for a black body at 290 Kelvin.

    While radiative transfer may be the dominant heat transfer process in the stratosphere you can pretty much forget it in the lower atmosphere where convection and condensing vapors dominate.

    If I have sent you this link before, please accept my apologies:
    Rodgigo Caballero (University College, Dublin):

    http://maths.ucd.ie/met/msc/PhysMet/PhysMetLectNotes.pdf

    The part most relevant to the present discussion starts on page 133. In particular you will note that when an atmosphere is opaque to upward IR radiation the effective radiating surface is raised.

  23. Mark Miller says:

    @Wayne:

    after reading in Petty’s book on radiation that 95% of surface radiation in co2’s lines is absorbed and constantly reemissions in the first meter, ~99% in the first 5 meters, then it all starts to make some sense. Seems we’ve been sold a bill of goods of co2’s high in the troposphere beaming back to the surface, doesn’t happen.

    Your comment was intriguing to me, but I’m having trouble nailing down what this means. When you say “95% of surface radiation in CO2’s lines is absorbed and constantly re-emitted in the first meter” are you saying that LWIR is being absorbed and re-emitted one meter from the surface of the earth? That would make sense to me, since I understand that CO2 is a heavier-than-air gas. It’s just that I’ve never seen this described this way. One would think that CO2 would mainly hang around at the surface.

    I tried arguing this once, and people with the alarmist view told me that it all eventually becomes evenly mixed and distributed via. air currents. I remember once hearing the story that SR-71 jet pilots were running into some phenomenon where they’d get black blotches on their windshields at the edge of the earth’s atmosphere. They turned out to be bugs thrown high up into the atmosphere by above-ground nuclear tests. They were just circulating around the earth up there, held aloft by the high winds. So that’s plausible, but it follows for me that the bulk of CO2 would still hang around at the surface, due to its relative weight to the other atmospheric gases, with some very small amount of the total volume at higher altitude.

  24. Mark Miller says:

    Re. my last comment

    Meant to say, “are you saying that some amount of LWIR is being absorbed and re-emitted by CO2 one meter from the surface of the earth?”

  25. Serioso says:

    For the ChiefIO and Mark Miller and others:

    Radiative heat transfer is governed by the Schwartzchild equation, and there are many texts and studies that describe it in great detail. Here’s a highly simplified picture:

    In the 14 micron band, radiation from the earth’s surface is absorbed by CO2 within a few meters of the ground. You can think of this as being the mean free path of a photon in that band. But the photon is immediately re-radiated in all directions. And absorbed and re-radiated more or less ad infinitum. This has nothing to do with the relative concentration of CO2 with altitude, which is more or less constant — that is, the ratio of CO2 molecules to N2 or O2 molecules doesn’t change much with altitude, but of course the absolute concentration of CO2 (molecules per unit volume) does decrease, and the mean free path gets longer and longer. Eventually, at very high altitudes, the mean free path becomes effectively infinite, and the photon escapes to space. The effective temperature at which escape occurs is about -50C (or, for that matter, around -50F).

    It is true that transmission in the 14 micron band does not quite become zero. But in some respects that doesn’t matter. Radiative heat transfer still occurs.

    Here is my number one question, and I’d love to know the answer: From what altitude in the atmosphere does the final emission occur?

  26. Serioso says:

    Another comment, assuming I am released from Moderator Hell in a timely fashion:

    I have read the link cited by gallopingcamel

    http://maths.ucd.ie/met/msc/PhysMet/PhysMetLectNotes.pdf

    which I find to be intelligent and comprehensive and thoughtful. However, It does not answer my main question (“from what altitude in the atmosphere does the final emission occur”). I realize my question was not adequately specific: I meant the altitude at which the final emission in the 14 micron band occurs. I am hoping that galopingcamel will be able to supply actual altitudes, not just formulae. Thank you.

    [/b>You might want to consider that phrases like "Moderator Hell" are direct insults "to the person" of the moderator and do not help your cause. When I see something like that in my 'early quick scan' of comments in moderation (when most are 'released from moderator hell' ;-) I just skip that comment. Clearly it will 'take some time' so I'll come back to it later. AFTER first cup of coffee (sometimes after two or three) when the energy level is higher and I'm more willing to engage with 'contentious folks'. AFTER I've read the comments from folks who have an open mic and respond to the more interesting ones. AFTER I've done a quick quake check (or market check if during trading hours). AFTER I've created any new posting that needs creating. Why? Some Evil Intent to keep poor "innocents" in Moderation Hell? Nope, not at all. Simple time management. ALL those things are of higher value than squandering time dealing with negative attitude folks tossing insults around and carping. IFF there is any time left, I come back to those comments. Later. IF the comment simply requires a long exposition to deal with it, that can be a LONG time later. If it just takes a 'snip' (which folks will notice I use VERY sparingly) or if it just takes a "please tone it down", it gets done fairly fast, usually the same day.

    So, I looked in the queue a few hours ago. Saw an insult "to the moderator" and had a couple of cups of coffee... checked on quakes (and interesting one in Africa, BTW), read about a fascinating food interval in the Louisianan / Mississippi area (during roughly the Iron Age Cold Period) and got recruited to wash the dishes by the spouse. Yes, she has priority over your comments. All of those things more valuable to me (well, except maybe washing the dishes) than dealing with the sniditude, gritching, and general negativity of things that get various folks comments put into the moderation queue.

    Now, if I had a staff of dozens of moderators running 24 x 7, I could indulge your demands for promptness on your schedule and meeting your demands. As I don't, I don't. Get over it.

    But don't worry, it only resets your 'days without insults and attack postures' counter to zero. Given a few hundred days comments with good behaviour you could still reach 'open mic' status...

    To your question:

    IMHO, the major radiation is likely from the hottest zone, the Stratopause. The air gets very thin above that (more gaps between molecules for IR photons to zip on out) and less water vapor and ozone to interfere with it too. Yes, it would be lovely to have a depth sounding satellite. (A nice example of a 'dig here!' to find such if it exists) But generally speaking, heat leaves from where it is hot and high. That's the 0 C point on the sky temperature graph in the Stratosphere, IMHO. The actual altitude will vary with the latitude (high in the topics, low in the arctic). There are plenty of IR photographs showing the high heat transfer at the stratospheric layer when clouds start to top out. That heat then gets mixed into the stratospheric flow and distributed poleward, where it then radiates away (net) per the image above. BTW, simple inspection of that image shows that the IR is NOT showing the terrain and weather features. Ergo it is stratospheric air patterns. -E.M.Smith ]

  27. kuhnkat says:

    Nick,

    you did not understand my question. How is emissions correlated with temperature. I somewhat understand BB radiation and that it is a composite of the wavelengths from material at a particular temperature. Gasses do NOT have enough differing material to fill in all those wavelengths to give a graph that would tell us the temp. How do they determine what temperature the gas is that is emitting the radiation especially regarding downward emissions.

    Again, molecules with a dipole apparently have fixed bands that they emit on due to this molecular configuration. Doesn’t matter what temp they are. How do we know what altitude the emissions are coming from?? Some will be temp based and some will be fixed due to being GHG’s. In a collision the emission can be triggered irregardless of the temp of the surrounding parcel.

    How do they know what temperature the emissions are coming from which is also asking how do they know what what altitude the emission is coming from.

  28. Serioso says:

    Wikipedia shows that there are three different altitudes consistent with a 220-230K emission temperature:

    These are 10-30 km, 70 km and 100 km. I was hoping gallopingcamel could, on the basis of what is on p.126 of his reference, help determine which is the appropriate emission level in the 15 micron CO2 band. I note that there is quite a difference in the slope dT/dheight in these three cases, and this has implications for any effects of increasing CO2 concentrations.

  29. Ian W says:

    If you want to see outgoing long wave radiation without it being averaged look here http://www.ssd.noaa.gov/goes/east/natl/flash-rb.html.

    You will find a good match with the water being convected up in weather as shown here http://www.ssd.noaa.gov/goes/east/natl/flash-wv.html

    Note that this is heat radiation – NOT atmospheric temperature. Latent heat release does not follow Stefan Boltzmann in any way.

  30. Ian W says:

    To add to my post above – note that the Geostationary satellites can ‘see’ the radiation from the water changing state – it is NOT being stopped by GHG or all being radiated seamlessly from a specific altitude. Instead you can track the activity of storms and fronts by watching the latent heat radiation.

    These concepts of a BB world with a GHG altitude for radiation would appear to be an artifact of mathematics based on assumptions and averages rather than observation based science.

  31. david says:

    How is emissions correlated with temperature.?

    Appears to be a good question as I understand non GHGs are not radiating, but they are conducting heat.

  32. adolfogiurfa says:

    @david (13:12:31) Just forgetting about words and more words as “temperature”. We are confused, mystified by words and “holy names”, Watts does not converse with Joules and both argue endlessly with those “horses of power” and so on….

  33. Ian W says:

    @david
    The first thing to remember is that in a gas ‘Temperature’ is not ‘heat’. Temperature is a measure of the sum of the kinetic energies of the molecules in the volume of gas. If the number of molecules in the volume is increased by raising the pressure, the sum of their kinetic energy increases (Charles Law). If it is agreed that non-GHG cannot radiate their kinetic energy away, then adding CO2 to a mix of N2 O2 will allow heat to escape the volume by radiation from CO2 molecules that gain heat by collision (conduction) with high energy N2 and O2 molecules. So adding CO2 will actually allow the volume of N2 and O2 to cool. Of course some radiation will be downward but more than half will be upward and transits downward through the denser atmosphere are more likely to hit another CO2 molecule than tranits up through the thinner atmosphere.

    Water molecules are more complicated as they can receive heat from collision with N2 or O2 and change state rather than gain kinetic energy. Therefore, the effect of adding water molecules is to lower the temperature of a volume of atmosphere while the volume still has the same energy content. The enthalpy of the volume is increased and is the reason for the ‘wet adiabatic lapse rate’.

    I have a nagging feeling that the lack of understanding of enthalpy by GCM modelers may be the reason for the lack of a mid-tropospheric hotspot.

  34. R. de Haan says:

    Nice observation from Hans Schreuder about “back radiation”

    http://climaterealists.com/?id=9004

  35. adolfogiurfa says:

    @Ian W I have a nagging feeling that the lack of understanding of enthalpy by GCM modelers may be the reason for the lack of a mid-tropospheric hotspot.
    shshsh…don´t say it aloud :-)

  36. E.M.Smith says:

    @Curt:

    Damn non-Imperial Units ;-)

    That’s what I get for going back to ‘tag’ everything with nm… Why can’t those European folks keep with one scale? Everything from wave numbers to micrometers to nanometers to …. OK, I’ll got back and clean it up….

    FWIW, all this focus on the particular scrap of data of 15,000 nm is missing the POINT. Look at the net radiative flux map. It is NOT coming from the ground, nor even from the top of the tropospheric events like thunderstorms. I is quite clearly coming from the well mixed stratospheric layers. Ground based radiative processes are just Not Relevant.

    Similarly, the whole bit with noticing that the stratospheric 0 C looks to be radiating was just the stimulus to go looking that got me to look at that net flux map. Frankly, if CO2 is blocking, that is even more evidence that IR radiation is just not relevant at the surface. ( I.e. it makes my case stronger that surface IR is just not relevant and IR is leaving from the Stratosphere or above.).

    @Ian W:

    It is just that difference between those IR images of cloud tops and the ‘net flux’ map that make it clear that CO2 and surface radiation are not pertinent to the process. Thanks for the links!

    @Adolfo:

    Oh, go ahead and say it ;-)

    @All:

    Sorry for the delay in responding. I’ve been a bit busy…

    @Adolfo and P.G. Sharrow:

    I think you’ll like the recent posting about Earth Plasmas…

  37. Mark Miller says:

    I’m remembering now how the alarmists have presented the theory of global warming, since we’d talked about earlier that they say that CO2 only reflects down. What they’d present sounded just like the simple model of the greenhouse effect. Light is allowed in, which generates heat. When the energy reflects off the surface, it changes to LWIR, which the “greenhouse” material (in this case, they argue CO2) reflects back to the surface. What they’d say is that the heat energy coming to the earth’s surface from the Sun passes through the “greenhouse” barrier because of its shorter wavelength. Now, with an actual greenhouse, some of the energy is reflected back, because glass is not a perfect conductor of light. Perhaps they’d concede that as well with CO2, though I haven’t heard them talk about it this way. What they’d say is that the longwave IR from the surface would get reflected back by the GHG, and as the concentration increases, so does the reflective capacity. They use Venus’s 98% CO2 atmosphere as their example of this…which to me does not make sense. In terms of CO2 in the atmosphere, the Earth and Venus are polar opposites.

    From what others have said on here, it’s sounding like GHGs reflect energy in all directions from a variety of bandwidths. It’s a matter of the gases’ concentrations at what altitude that determines how much is reflected.

  38. E.M.Smith says:

    @Mark MIller:

    It’s also the case that right next to any ‘closed’ window there is a wide open window…

    As the CO2 whacks into the other molecules in the air and spreads the energy around, there are lots of other species that can send energy to space (as evidenced the IR pictures of heat being dumped at the tops of clouds via water vapor… and IR images of the surface showing tanks and soldiers at night…)

    It’s like arguing that because the window is closed, the heat will not be going out the open door right next to it…

Comments are closed.