Of Course The Greenhouse Effect Is Real

Anyone who lives in a cold climate knows that a cloudy night will feel much warmer than a clear night at the same temperature. This is because of downwelling longwave radiation from the clouds – i.e. the Greenhouse Effect. H2O and CO2 do the same thing, to a lesser extent.

About Tony Heller

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89 Responses to Of Course The Greenhouse Effect Is Real

  1. Anyone who lives in a cold climate knows …

    Not everyone. A Boulder woman—bless her heart—told me on a cloudy early spring night that it was warmer because of climate change.

  2. mjc says:

    And yet, it isn’t.

    Basically, it’s not that simple. There are several mechanisms involved, one of which is DLWIR. You can’t really separate them out and say just one is ‘The Cause’. Major cause, primary cause…maybe; sole cause, not even close.

    • Gail Combs says:

      mjc says:
      “And yet, it isn’t.

      Basically, it’s not that simple….”
      >>>>>>>>>>>>>>>>>>>>>>>

      Correct. Steve’s comment is mixing the several different effects of water with CO2’s grabbing a photon and passing it on to other atoms/molecules in the air..

      For example for water there is the latent heat of evaporation.

      Energy is absorbed by water and it moves from the liquid phase to the vapor phase WITHOUT changing temperature. When dew forms during the night the latent heat energy is released. High humidity, without clouds lowers the day time high temperature and raises the night time low temperature.

      Sleepalot did a quick and dirty look at this effect of the addition of water vapor (~ 4%) in Barcelos, Brazil (Lat: 1 South, Average humidity 90%) vs the dry atmosphere in Adrar, Algeria (Lat: 27 North, Average humidity around 0%) and I expanded on it here and here.

      Long story short, the effect of the addition of water vapor is not to raise the temperature but to even the temperature out. The monthly high is 10C lower and the monthly low is ~ 10C higher when the GHG H2O is added to the atmosphere in the example comparisons above.

      The average temperature is about 4C lower in Brazil despite the fact that Algeria is further north above the tropic of Cancer. Some of the difference is from the effect of clouds/albedo but the dramatic effect on the temperature extremes is also from the humidity. That 4C lower would probably be the energy bound up in the water vapor as latent heat energy.
      …………

      Then there have been two recent comments by physicists that have shed a glaring light on the subject of CO2 back-radiation. To me it was a real EUREKA moment.

      Here on Steve’s blog gallopingcamel (Peter Morcombe) wrote a comment on the subject on stevengoddard(DOT)wordpress.com/2014/05/24/whats-up-with-that/#comment-357834

      …. a molecule cannot emit a photon unless it has first been raised to an “excited state”. The lifetime of these excited states is typically measured in micro-seconds or milli-seconds.

      If left undisturbed, excited atoms or molecules will eventually give up their excess energy via radiative transitions to lower energy states or via collisions with other molecules. When total pressure is low, radiative transfer dominates so the outgoing radiation is absorbed by CO2 (or water vapor) is re-radiated isotropically. This means that half of the outgoing radiation is returned to the surface exactly as claimed by Trenberth & Co.

      In the troposphere the mean time between collisions is quite short (~200 pico-seconds) so most of the outgoing IR radiation absorbed by complex molecules will be lost in collisions before a photon can be radiated. This means that in the lower atmosphere it makes no difference whether the energy is transfered by radiation or by convection. In either case the energy is retained in the troposphere.….

      Dr. Robert Brown of Duke wrote, this comment over at WUWT on May 28, 2014 at 10:21 am verifying Gallopingcamel’s understanding of the physics.

      ….That’s the effective surface area intercepted by each CO_2 molecule. It is large enough that the mean free path of LWIR photons in the pressure-broadened absorption bands of CO_2 in the lower atmosphere is order of a meter. That means that LWIR photons — whatever their “size” — with frequencies in the band go no more than a meter or few before they are absorbed by a CO_2 molecule.

      The lifetime of the excited state(s) is much longer than the mean free time between molecular collisions between the CO_2 molecule and the (usually nitrogen or oxygen or argon) other molecules in the surrounding gas. That means that the radiative energy absorbed by the molecule is almost never resonantly re-emitted, it is transferred to the surrounding gas, warming not just the CO_2 but the oxygen, nitrogen, water vapor, argon as well as the other CO_2 molecules around. Periodically CO_2 is thermally excited in-band by just such a collision and radiates energy away, but it is not like an elastic scattering process such as occurs in specular reflection within clouds. In band/thermal radiative energy gradually diffuses upwards, with the mean free path of the photons increasing the higher one goes, until it starts to equal the remaining depth of the atmosphere and photons emitted “up” have a good chance of escaping, cooling the molecules (on average) that emit them. It takes order of 100s of absorptions and emissions for radiation to diffuse upward to escape, and there is an almost equal probability that radiation will diffuse downward (especially from the lower levels) where we observe it as back-radiation/greenhouse radiative forcing of the surface.

      Even this is oversimplified. Because of pressure broadening, molecules close to the ground emit photons “in the wings” at frequencies that less broadened molecules at higher altitudes/lower pressures are nearly transparent to. That means that there is a steady CO_2-mediated “leakage” even from lower altitudes directly to space from the edges of the monotonically decreasing-with-height absorptive bandwidth. It also means that there is a MAJOR change in atmospheric absorptivity/emissivity with simple high and low pressure centers as they move around, as well as a modulation of the size of the emission-wing “hole”.

      Grant Petty’s book can walk you through much of the physics.

      If I read these comments correctly, CO2 WILL absorb the outgoing IR photons in the correct wavebands but the overwhelming pathway is for the energy to be transfered to the rest of the atmospheric molecules warming them. At that point, since hot air rises the energy is carried up. Of the small number of CO2 molecules that do emit a photon instead of transferring energy via a collision, a second ‘reaction’ is for the excited CO2 to emit at frequencies “in the wings” half of that energy escapes through the emission-wing “hole”. Therefore the “Downwelling radiation” from CO2 is a tiny fraction of the amount the Climastrologists are claiming. AND since “LWIR photons — whatever their “size” — with frequencies in the band go no more than a meter or few before they are absorbed by a CO_2 molecule,” Therefore additional CO2 in the atmosphere means diddly squat.

  3. bretshroyer says:

    H2O and CO2 do the same thing, to a lesser extent.

    Do you mean that H2O and CO2 do the same thing as clouds, or that H2O and CO2 do the same thing as each other? (though to lesser extent)

  4. mkelly says:

    On this one we will have to disagree.

    • Gail Combs says:

      I think Steve likes to toss a cat among the pigeons just to watch the fun.

      I am no physicist but the effects of the latent heat of vaporization can be seen if you look as Sleepalot and I did.

      Willis Eschenbach’s Thermostat Hypothesis (where there is water) also can be verified by looking at the thunderstorm formation in the summer up the east coast of the USA. If I remember correctly, the number of thunder storms decreases going from ~2/3 of the days in Florida to ~1/3 of the days in NC and becomes sporadic north of Fayetteville NC where temps get cooler than 90-95F in the afternoon.

      Unfortunately the effects of water CAN be seen by the lay person and then can be conflated with CO2 by the propagandists.

      • mkelly says:

        I have no problem with the latent heat, but CO2 has no latent heat capability. Any radiation from CO2 or H2O reaching the surface has no effect. Insulation by the clouds is not the same as DWLWIR warming the surface of the earth.

        Of course as you point out Steve maybe just throwing a pigeon out to see what happens.

        • CO2 absorbs LW radiation of certain frequencies. Instead of immediately disappearing into space, that energy remains in the earth’s atmosphere a little longer and keeps the temperature up.

      • there is no substitute for victory says:

        Try this little experiment. This fall when the overnight temps dip into the 40-30 degree range watch at Sundown or bedtime whether or not there is any cloud cover. Then at Sunrise check for clouds and whether there is any frost on your lawn or car windows.

        The same thing works when predicting whether there will or will not be fog the next morning. Clear windless nights result in morning fog because the relative humidity rises (as in becomes greater not higher) with cooling conditions associated with clear skies. Morning fog becomes frost when there are calm and clear conditions on chilly nights. This is because the ice crystals you see on frosty mornings are the result of fog or dew freezing to every cold thing that it touches. Cloudless nights promote cooling, cloudy nights retain heat, this is the result of water vapor in the clouds acting like the green house gas thing that water vapor is. If on the other hand the temperature is too low, then all or almost all of the humidity has already been wrung out of the air and that is why you see little or no frost or fog on really cold as opposed to just chilly mornings.

        Wow! You thunk I could quantify myself fur me sum of ‘them there’ government graints?
        I shore hop soo caus my cow done died an I shore nead to by I anotherone.
        I included the two sentences above to illustrate how vastly smarter a complete illiterate is when compared to most Climate Science PhDs or sadly today, even the average citizen.

  5. mellyrn says:

    And a cloudy DAY will feel cooler. Where’s the “downwelling IR” there?

    The glass of a greenhouse absorbs IR — and then the glass does something that no “greenhouse gas” can do: it stays right there, being all warmed up, exchanging energy with whatever else is also right there. Gas, otoh, disperses, carrying its energy away and away — up, usually; you know, closer to space.

    • Obviously cloudy days often feel cooler because there is less SW radiation, which is blocked by the clouds.

      • tom0mason says:

        So downwelling LWIR happens 24/7? So why the fudge are we building solar collectors in California’s Mojave Desert Solar project, Should it not collect and concentrate all the LW IR energy that’s available 24/7?

        This will also reduce the fried bird problem currently encountered, as the so called LW ‘back radiating’ IR is so mysterious it will not even burn matter, but can heat it – immeasurably.
        Remarkable because of CO2 with untapped powers to confuse nature.

        • Curt says:

          Tom: You ask: “why the fudge are we building solar collectors in California’s Mojave Desert Solar project, Should it not collect and concentrate all the LW IR energy that’s available 24/7?”

          Because if the radiation is coming from a colder source (and LWIR from the atmosphere is almost from a lower temperature level than the surface), your “collector” will ALWAYS radiate more energy to it than it does to the collector.

          So what difference does it make? Well, it certainly provides more energy to the surface than if there were no atmosphere or if the atmosphere had no gases that could radiate in these bands. My undergraduate engineering heat transfer textbook, written in the 1960s, gave the rule of thumb that a clear night sky should be treated as having an “effective blackbody temperature” for the purposes of radiative heat transfer analysis of about -20C (253K). That’s still a lot greater than the 3K of deep space.

          Before they are launched, virtually all man-made satellites go through thermal testing in a special vacuum chamber where the walls are cooled with liquid nitrogen. The vacuum is to eliminate conductive/convective heat transfer; the liquid nitrogen cooling is to virtually eliminate the LWIR from the walls, which would not be present in space.

          If you are sitting indoors in a climate-controlled room, you are bathed in an ambient LWIR of about 400 W/m2. You are so used to this that you generally don’t realize that it is there.

        • Gail Combs says:

          YES!
          DWLWIR should be a source of energy capable of performing work!

          Trainbreath shows us the value for DWLWIR is 324 w/m2 and even shows it with a downward pointing vector arrow. That is 324 w/m2 of incoming energy 24/7/365 while the incoming solar that heats the earth is only a very fickle 161 w/m2.

          After all my microwave oven can boil water so why shouldn’t Trainbreath’sr DWLWIR?

          Why aren’t UN, IPCC and USA scientists working on this vast unharvested energy source!

          This is HUGE folks we need to get Al Gore and McKibben on board and start a campaign. Write to our Senators and Congressmen. Write to Obama!

        • tom0mason says:

          🙂
          Hurray free energy again!

  6. Tony B says:

    Couple of observations and questions for those more knowledgeable than me.
    The low level atmosphere on a given day/night has a temperature lapse rate with elevation. On a clear night, a temperature inversion sets up quickly after sunset near ground level and gradually moves higher as the night goes on before resuming the lapse rate that existed during the day at some point.
    On a cloudy night, the inversion is not as likely, with the temperature lapse rate from daytime hours roughly maintained throughout the evening hours.
    I have a tough time assigning this to Greenhouse Effect. The downwelling LWR from the Greenhouse Effect supposedly inhibits heat loss from the ground? Are you sure of this?
    As an example: the ground in direct sun heats up to a temperature greater than the ground in shade under clouds. You would expect a rapid loss of heat from ground previously in sun, but now in the dark as compared to ground that has been in cloud shadow going into darkness.
    I suspect if you look at the atmospheric lapse rates and ground temps, the only difference between sunny and cloudy days is the temperature of the ground and the atmosphere very close to it. Lapse rates from elevations from a few hundred feet up show very little difference until getting into the cloud level where latent heat changes the slope. Can anyone enlighten me as to where I’m wrong?

    • Curt says:

      Tony:

      Let’s take night time first. On a clear night, the surface, with its very high emissivity, can radiate energy to high in the atmosphere, or in some wavelengths, directly to space. (If there were no greenhouse gases, it would radiate directly to space at all wavelengths.)

      This allows it to get colder than the low atmosphere. (This is why you can get frost on the surface on nights where the air temperature at the surface never gets down to freezing.)

      In response, the atmosphere starts transferring energy to the surface through conductive/convective means, and – voila – you get a negative vertical temperature gradient, aka a temperature inversion. The poles, where night lasts for many months during winter, can have an inversion that lasts for months.

      Last winter, I drove high into the California Sierra mountains on a clear winter night. At sea level, the temperature was 0C. The temperature steadily increased as I went up in elevation, all the way to +8C at 2000-meter elevation. That’s quite an inversion!

      Now when the sun comes up, it transfers energy to the surface more than it does to the atmosphere, and so gets to a higher temperature than the air immediately above it, allowing it to transfer energy to it through conductive/convective, evaporative, and radiative means. Now you get a positive temperature gradient, up to what we refer to as the lapse rate (which really should be thought of as a limit).

      You ask, “The downwelling LWR from the Greenhouse Effect supposedly inhibits heat loss from the ground?” You can think of this in a couple of different ways. Most physics and engineering textbooks explain radiative heat transfer in terms of “radiative exchange”, where each body radiates power as a function of its temperature and emissivity only, and the resultant heat transfer is the difference between these (through a common geometry of transmission). Others prefer to consider the different temperatures and emissivities as giving a “potential” difference (like voltage or pressure) resulting in a one-way transfer. Either way you get the same result.

      Enough for now…

      • I didn’t ask any such thing. People who try to put words in my mouth completely piss me off.

        • Tony B says:

          I didn’t quote you Steve/Tony. Just trying to put a question out to the general readership and I apologize if my grammar was obtuse. Wasn’t intended that way and was probably a reflection on my limited knowledge of the subject matter.

        • Curt says:

          Steven/Tony H:

          I was replying to Tony B’s question in the comment above. (I still think of you as “Steven”, so I forgot to make it clear.)

      • Tony B says:

        Thank you greatly for your comments. Reading all the comments here have been enlightening.

  7. geran says:

    A REAL greenhouse works like this: When it is necessary to “trap” heat, the greenhouse windows are closed. Visible wavelengths penetrate the glass. The visible wavelengths are absorbed and used up (by photosynthesis), or re-radiated in longer wavelengths. The longer wavelengths are trapped, because they cannot penetrate glass. In the heat of the day (bright sunlight), the windows must be opened or the plants will die due to the extreme heat. At night, the windows are closed to keep the IR wavelengths contained.

    The Earth has no such mechanism. There is no “glass” in the atmosphere that can “trap” heat. The atmosphere is largely a cooling mechanism that radiates excess heat to space.

    (Yes, clouds are different, but they are water vapor, not CO2.)

    • Gail Combs says:

      geran says:
      ….(Yes, clouds are different, but they are water vapor, not CO2.)
      >>>>>>>>>>>>>>>
      Actually clouds are water and ice droplets (visible liquids and solids) so they are different than water vapor (invisible gas)

      If you have never read this it is an incredible story of the forces of water in the atmosphere: Rider on the Storm

      • geran says:

        Darn, Gail “corrects” me again, but only provides one link from her library. I must be slipping….

      • mkelly says:

        Rider(s) on the Storm. Great song by “The Doors”.
        https://www.youtube.com/watch?v=k9o78-f2mIM

      • geran says:

        Surely Gail is going to supply us with 5-6 links describing how ice crystals are formed without water vapor.

        We are so eager to learn.

        • Gail Combs says:

          geran, the data I put together looking at Barcelos, Brazil was for high humidity days with no rain or clouds. So yes I do differentiate between them.

          Clouds mean the latent heat has been transfered back to the atmosphere as well as other complications like reflecting incoming sunlight.

        • geran says:

          Please provide links for cloud formation without water vapor.

        • PeterB in Indianapolis says:

          Gail didn’t say that clouds formed without water vapor. Gail said that clouds are COMPOSED OF liquid and solid water, which obviously has to come from somewhere – and that somewhere would be… WATER VAPOR. However, if you are SEEING a cloud, you are NOT seeing water vapor, you are seeing liquid and solid water. You cannot see water vapor, it is a clear, colorless gas. When you boil a pot of water and see the steam above it, you are not seeing water vapor, you are seeing liquid water RECONDENSING from water vapor.

          In transitioning from vapor to liquid and solid forms (by forming clouds) water gives off heat…

  8. Rosco says:

    A glass greenhouse does NOT trap radiation – full stop !!!

    Glass is fairly transparent to all wave lengths below about 4 micrometres – so all that IR simply escapes no problem.

    Above 4 micrometres glass is practically opaque to IR and thus absorbs it BUT glass has a high emissivity – it is practically 1 well 0,94 which is practically 1 !

    This means glass practically meets the definition of a blackbody – a glass greenhouse does not trap radiation it suppresses conduction/convection.

    The radiation from clouds is not the reason why it feels warmer on a cloudy night. Again the suppression of conduction/convection is the prime reason. The same effect can happen on a completely cloud free night if a temperature inversion develops.

    The radiation from a cold object has probably no thermal effect on a warmer object. This was practically demonstrated a couple of hundred years ago where it was shown by experiment.

    And Einstein and Max Planck provided the mathematical explanation for why this is so.

    A photon has energy which is dependant on the frequency or wavelength of the emission – intensity has nothing to do with it – this was the result of Planck’s and Einstein’s Nobel Prizes !!!

    E = hf.

    If a photon does not have the “right” wavelength – hence right energy – it has no effect on atoms or molecules either sub atomically or gross vibration modes.

    Einstein proved this by his analysis of the photoelectric effect where a photon is either absorbed totally ejecting an electron from the metal or it does nothing at all. It formed the basis for the Bohr model of the atom and is still used to theoretically determine vibration modes of molecules.

    It is also interesting to note the theory predicts a vibrational mode for CO2 which does not show up in experiment so perhaps some of the theory needs further work !

    The process is an all or nothing process – all the physics text books teach this AND it is especially so for gases which have few absorption lines.

    CO2 absorbs less than a few percent of infra-red photons and none of the visible or higher wavelengths. It is almost transparent as well – narrow bands at 2.7, 4.3 and 15 microns.

    And to talk about pressure broadening when the partial pressure of CO2 is 0.04 kPa is ludicrous.

    Brown is a alarmist in disguise – Einstein and Planck disagree with his brand of pseudo-science.

    CO2 absorbs only certain LWIR photons and the vast majority simply pass through – this is a scientific fact that has been known since spectroscopy was discovered – gases do not display a continuous spectrum – only solids and liquids do !

    Gases are always practically transparent to most electromagnetic radiation.

    Who really cares about CO2 and the 2.7 and 4.3 micron bands ? These coincide with the peak emission of objects at 800 and 400 degrees C – not too many of those lying around.

    Who really cares about CO2 and the 15 micron band ? This coincides with the peak emission of objects at minus 80 degrees C – not too many of those lying around except in Antarctica.

    This is why the “thermodynamics” alarmists use to convince you they know what they say is total BS – Einstein and Planck proved then wrong decades ago,

  9. Dave1billion says:

    This thread is why I like reading this blog.

    Unlike the incestuous, back-slapping hallelujah choristers in the AGW crowd, this group has a lot of people that are quick to question just about everything.

    And not only question it, provide alternative hypotheses/explanations.

    Keep it up, skeptics.

  10. Gail Combs says:

    Rosco,

    I thought it was NaCl that was transparent to IR and that is why we use slabs of salt in IR spectrophotometers instead of glass microscope slides and cover slips.

    Do gases have spectral lines? yes
    Does water vapor cover the CO2 spectal lines? Yes

    and that is why the amount of Trainbreath’s downwelling radiation — 333 WM2 (vs 184 WM2 for solar @ surface) is so idiotic. Exactly how much of that is actually latent heat from water phase changes? You never hear a warmist say.

    The key points of Dr. Brown and Peter Malcombe is CO2 is saturated in the first meter from the surface and the IR energy is handed off to other molecules via collision.

    That shoots down CAGW. The rest is quibbles about how much CO2 there is in Unicorn farts.

    Two good essays on Trainbreath’s cartoon:
    http://theinconvenientskeptic.com/2010/11/the-difference-between-forcing-and-heat-transfer/
    http://theinconvenientskeptic.com/2010/11/the-earths-energy-balance-simple-overview/

  11. Rosco says:

    If nitrogen and oxygen cannot radiate at ambient temperatures and do not absorb IR then they acquire energy and thus increase their temperature by conduction/convection.

    Rising in the atmosphere may result in a lower temperature because kinetic energy is transformed into gravitational potential energy but this is not a loss of energy – it is a transformation.

    The only loss of energy by the Earth’s atmosphere is to radiate.

    If N2 and O2 – 99% of the atmosphere – cannot radiate the only mechanism whereby the energy they gain when they “heat” up is by a relatively rare collision with radiative active gases which never constitute more than a couple of percent of the atmosphere !

    OR most of the surface radiation simply goes straight from the surface to space through the IR “window” from about 8 – 14 microns wavelength.

    In this range only Ozone significantly absorbs IR. As this occurs some 20 – 30 km above the surface in the stratosphere there is almost zero chance of this radiation returning to keep you toasty warm.

    All of the arguments I see about GHGs acting like a blanket are con jobs.

    If you stand naked in a cold large room the chance that your body heat will warm that room are miniscule. Hop into bed covered by a blanket which traps the air close to your body and you stand a fighting chance of retaining the “heat” you otherwise simply lose and this keeps you warm.

    It has nothing to do with back-radiation making you hotter than you were before as alarmists like Brown claim. It is simply a matter of effectively using a heat source to warm a small area rather than pissing the “heat” away.

    Put you radiator in the front year and you’re wasting electricity, put it in your confined lounge room and it has a benefit, put it in a cardboard box and it bursts into flames and burns your house down.

    But the element is always at the same temperature – it is not getting hotter!

    Even Neanderthals understood this when they decided to move the fire inside the cave but “modern physicists” cannot seem to grasp this !

    • Sleepalot says:

      “If nitrogen and oxygen cannot radiate at ambient temperatures”
      Aurora Borealis. That’s N2 and O2 well below Tambient, emitting visible light.

    • Sleepalot says:

      I don’t know, but suspect, that two fast moving molecules colliding can result in two slow moving molecules plus an emitted photon of IR – and that that’s how O2 and N2 cool.

  12. Edmonton Al says:

    It is my understanding that Arrhenius believed in Aether.
    He postulated that the aether simulated the glass in a greenhouse and would “trap” heat.
    CO2 would be “trapped” and green the earth.
    Mickelson-Morley debunked the aether belief, and hence, the GHG Theory is invalid.
    http://greenhouse.geologist-1011.net/
    and:
    http://arxiv.org/PS_cache/arxiv/pdf/0707/0707.1161v4.pdf

  13. Gail Combs says:

    Rosco says:
    September 4, 2014 at 9:52 pm

    If nitrogen and oxygen cannot radiate at ambient temperatures and do not absorb IR then they acquire energy and thus increase their temperature by conduction/convection…..
    >>>>>>>>>>>>>>>>>>>>>
    AND via collision with IR absorbing gases like H2O and CO2.

    All Dr. Brown was saying was because the chance of energy transfer via collision was much greater than the chance of emitting a photon, ESPECIALLY near the surface, CO2 (and I assume water vapor) acts like conduction/convection. It helps heat up the other molecules of the air. What it does NOT do is toss a photon back towards the surface except in very rare cases.

    When the air pressure is less and thus the mean distance between molecules is a lot greater, THEN emitting a photon becomes more likely than transfer of energy via collision.

    Think about what that means.

    At height CO2 becomes a radiator and where is it most likely to NET radiate towards? SPACE! Any radiation towards earth is going to get intercepted at lower altitudes by water or CO2 and passed of via collision to the other gases in the atmosphere.

    The net result is ‘Back radiation’ from CO2 to the earth is scarcer than hen’s teeth.

  14. Gail Combs says:

    So “down welling radiation” is a fallacy.

    What about “The blanket effect”

    Thermo was not my favorite course in College so I am going to let John Kehr, a chem Engineer explain:

    Part 1: Radiative Heat Transfer – Overview

    Part 2: Radiative Heat Transfer: Medium Overview, Part 1 of 2.

    Part 3: Radiative Heat Transfer: Medium Overview, Part 2 of 2.

    The upshot is
    Photon from Sun ===> Ground
    Photon from Ground ====> CO2
    Energized CO2 ====> other molecules in atmosphere (net warmer)
    Warmer atmosphere reduces the amount of energy transfered from the earth to the atmosphere.

    This is pretty darn obvious when you think about it. Dump Ice cubes in boiling water (like I do with my tea every morning) and soon the whole cup of water is the same temperature (equilibrium) but it does take a few minutes. Since the atmosphere is miles thick it takes a lot longer (thank goodness) and by the time things start to really cool off the sun is back up and more energy gets dumped into the entire system.

    Where things get complicated is water. As in oceans acting as a giant hot water bottle, clouds blocking energy transfer up or down, water vapor/thunderstroms acting to short circuit the orderly transfer of heat and transfer large amounts straight to the tropopause…..

    • geran says:

      What is “pretty darn obvious” is that you don’t understand the physics. Dumping ice cubes in your tea is NOT a model of the atmosphere.

      (Maybe more links will help your argument?)

      • Gail Combs says:

        I was using my tea to illustrate the idea of equilibrium. (sorry for the confusion)

        If the earth’s surface and the atmosphere above it are the same temperature you are not going to get any net transfer of energy. Only when the atmosphere is cooler than the surface do you get a NET transfer of energy.

        The idea of a net transfer of energy vs energy potential is where Trainbreath is scamming people.
        Trainbreath’s cartoon

        …is reasonably accurate, but it is also entirely misleading. The two large energy flows named Surface Radiation and Back Radiation are different from all the others. They are not measures of energy transfers, but of radiative flux (also called forcing). As I have described before, there is a difference between energy transfers and radiative flux. Two objects at the same temperature have zero net energy transfer and as a result, will not change temperature. As the surface of the Earth and the atmosphere above have a small temperature difference (to be shown in a later article), there is little energy transfer between the two….
        http://theinconvenientskeptic.com/2010/11/the-earths-energy-balance-simple-overview/

        I hate the term ‘Forcing’ because I consider it very misleading especially when it does not mean anything is being “forced” but only means there is potential energy stored. But what else is new in a post modern PC world where words swap meaning at a whim?
        The Difference between “Forcing” and Heat Transfer

        The temperature is 10 °C (50 °F). Based on the previous article that temperature means that the air has a “forcing,” or radiative flux of 364 W/m2. As a normal human your surface temperature is 35 °C and your “forcing” level is 511 W/m2….

        For a cool autumn day the sun is likely providing 100 W/m2 of energy. The difference is the sun is transferring energy to the objects that it reaches.

        That is the difference between energy transfer and “forcing.” One is simple and direct. Energy is flowing and the temperature of something is changing. The other is the potential for heat transfer. If a person were placed in space, that potential heat transfer would become an actual heat transfer of 511 W/m2. That would cool a person down very quickly.

        That is why the 364 W/m2 of potential heat transfer from air that is 10 °C will not warm you up, but the actual heat transfer of 100 W/m2 from the sun will. The effect from the forcing is that without it you would lose heat even faster. It does not warm you, but it limits the amount of energy that you lose….

        • geran says:

          Cool, 3 more links. Boy, someday I will be smart, if I keep all these links….

        • PeterB in Indianapolis says:

          Mebee if you read what the papers said that she was linking to, but if not, then no.

        • Sleepalot says:

          Gail, Geran is trolling you: getting you to write well researched essays without cause:
          he even got you to appologise!

          Geran wrote: What is “pretty darn obvious” is that you don’t understand the physics.
          Reply: Empty rhetoric.
          Geran wrote: Dumping ice cubes in your tea is NOT a model of the atmosphere.
          Reply: Correct.

          That’s all you needed to write.

    • PeterB in Indianapolis says:

      Of course “downwelling” radiation is a fallacy. Radiation is emitted in all directions simultaneously, not in a single direction. Radiation doesn’t know up from down (or sideways for that matter).

  15. Gail Combs says:

    This graph gives a really good idea of how fast the earth loses energy (temp) when there is no water vapor in the air. It is the temperature readings of the air and sand during an eclipse in the Libya desert.

    http://www.shadowchaser.demon.co.uk/eclipse/2006/thermochron.gif

  16. nielszoo says:

    The “greenhouse” thing drives me nuts. I don’t see a glass roof over our planet therefore… NO greenhouse! Are there minor differences in the ability to capture different wavelengths of radiation in different gasses… yes. Looking at atmospheres in the rest of out solar system you will notice that the denser atmospheres are warmer than the lighter ones. The denser the atmosphere the more energy it can hold in heat. The denser the atmosphere the more energy can be transferred by convection. The denser the atmosphere the more heat can be transferred from the surface of the ground (heated by solar radiation) via plain old mechanical heat transfer and not esoteric “back radiation” (another term that drives me nuts.) I’m sure the regulars here know these but for those who like numbers take a look at this nice flyover by Nasif Nahle that walks through all the thermodynamics of why the insignificant amount of CO2 ain’t doin’ diddly:
    http://www.biocab.org/Heat_Storage.html

    …and one on CO2’s gozeinzas and gozeoutas radiation wise:
    http://www.biocab.org/Emissivity_CO2.html

  17. DakotaKid says:

    The real check of the CO2 and water vapor affect on surface temperature:
    If the change in temperature between day and night in a given area decreases there is a greenhouse affect that was not there before.
    If the overall temperature decreases and the average difference between day and night decreases it is due to water vapor as cloud cover reflects the majority of radiation back into space and there is net cooling, with greenhouse affect the day to night temperature difference decreases.
    If the overall temperature increases and the day to night temperature difference decreases the overall effect shows greenhouse affect from non condensing gasses (CO2, methane, etc.).
    If the overall temperature rises and the difference between day and night increases, it shows the dominant cause for increase in temperature is radiative forcing(most probably increase in solar flux at the wave lengths absorbed by the land and ocean) as the radiative energy loss increase is proportional to the fourth power of the temperature for any gray body.
    If the day to night temperature difference stays the same and the and the temperature increases, either there is a balance between increase in greenhouse gasses and increase in radiation (very improbable) or the data are being cooked.

    • DakotaKid says:

      Check the temperature data in desert areas that have 100 years of data, and the truth will show consistency with the noncondensing greenhouse gasses or it will contradict them actually proving the model true or false.

      • Gail Combs says:

        You would also have to include differential heating by the sun.

        NASA has found that although TSI is relatively constant the percentage of EUV, UV Vis and IR changes. Since the atmosphere acts as a ….. Dang, all I can think of is a gas chromatograph and differential absorption….

        Any way the atmosphere does not transmit all wavelengths to the earth’s surface so if the % energy in different wavelengths changes then the net amount of energy the sand/soil absorbs will change and that will cause the air temperature to change.

        Nasif Nahle was making that point in those two articles nielszoo linked to

        http://www.biocab.org/Heat_Storage.html
        and
        http://www.biocab.org/Emissivity_CO2.html

    • Gail Combs says:

      OK,
      Now that I am awake and can see better, I read that more closely.

      You are completely leaving out the latent heat of evaporation or calling it the ‘Greenhouse Effect’ in your scenarios, at least in this one:

      If the overall temperature decreases and the average difference between day and night decreases it is due to water vapor as cloud cover reflects the majority of radiation back into space and there is net cooling, with greenhouse affect the day to night temperature difference decreases.

      I covered that scenario in this comment linking bact to some observations done by Sleepalot with additions by me.

      Sleepalot pointed out the actual effects of the GHG water vapor on the temperature by comparing high vs low humidity.
      For May 2012, Barcelos, Brazil (Lat: 1 South)
      Temp: monthly min 20C, monthly max 33C, monthly average 26C
      Average humidity 90%

      For May 2012, Adrar, Algeria (Lat: 27 North)
      Temp: monthly min 9C monthly max 44C, monthly average 30C
      Average humidity around 0%

      He picks May which is midway between the vernal equinox and the summer solstice and therefore the sun would be midway between the equator and the Tropic of Cancer (the latitude line at 23.5° North) so the solar insolation at both locations would be roughly equal with a bit more expected in Barcelos, Brazil.

      One would expect a drop in temperature of ~ 4C due to altitude for Adrar, Algeria so the difference between locations, taking into account altitude is ~ 8C higher in Adrar which is further north but with much lower humidity.

      I took a rough look at the data from Brazil.
      Twelve days were sunny. I had to toss the data for two days because it was bogus. The average humidity was 80% for those ten days. The high was 32 with a range of 1.7C and the low was 22.7C with a range of 2.8C. Given the small range in values over the month the data is probably a pretty good estimate for the effects of humidity only. You still get the day-night variation of ~ 10C with a high humidity vs a day-night variation of 35C without and the average temp is STILL going to be lower when the humidity is high.

      This data would indicate the ‘GHG’ water have two effects. One is to even out the temperature (he average difference between day and night decreases)and the second is to act as a “coolant” (overall temperature decreases) at least if the GHG is H2O no doubt due to latent heat of evaporation. This is all with only water vapor’s latent heat of evaporation and WITHOUT CLOUDS or CO2!

      As I said. CO2 is a flea compared to water.

  18. geran says:

    DakotaKid says:

    The real check of the CO2 and water vapor affect on surface temperature:
    If the change in temperature between day and night in a given area decreases there is a greenhouse affect that was not there before.
    >>>>>
    Unbelievable (The Sun has not effect!)

    If the overall temperature decreases and the average difference between day and night decreases it is due to water vapor as cloud cover reflects the majority of radiation back into space and there is net cooling, with greenhouse affect the day to night temperature difference decreases.
    >>>>>
    I think he is trying to make sense, but the drugs are some how interfering. (Translation for the Kid, toe dgurs art interring.)

    If the overall temperature increases and the day to night temperature difference decreases the overall effect shows greenhouse affect from non condensing gasses (CO2, methane, etc.).
    >>>>
    If you owe money on your cable bill, you now owe triple that amount. (No translation necessary for the Kid.)

    If the overall temperature rises and the difference between day and night increases, it shows the dominant cause for increase in temperature is radiative forcing(most probably increase in solar flux at the wave lengths absorbed by the land and ocean) as the radiative energy loss increase is proportional to the fourth power of the temperature for any gray body.
    >>>>>
    You can’t trust someone that flunked physics.

    If the day to night temperature difference stays the same and the and the temperature increases, either there is a balance between increase in greenhouse gasses and increase in radiation (very improbable) or the data are being cooked.
    >>>>>>
    Flunked physics and drugs are not a good mix.

    • DakotaKid says:

      I make my living as a physicist.

      • geran says:

        I kinda thot so….

      • Edmonton Al says:

        DK… Does a gas in an open system expand when it is heated?
        A greenhouse is a closed system. The atmosphere is an open system.
        A gas in a closed system [greenhouse] heats up because the volume stays the same.
        In an open system[atmosphere] the gas expands when heated and rises .
        It is a coolant

        • Sleepalot says:

          Ed. Al said “The atmosphere is an open system.”
          (btw, Iana scientist.)
          That’s a tricky one. A greenhouse has a base, sides and a roof. The atmosphere has a base – the land/sea surface: it needs no sides, because it’s spherical – the air is constrained, laterally, by itself: the atmosphere has no roof, but is constrained by gravity.
          It may not be as confined as a greenhouse, but I don’t think the atmosphere is entirely “free”. (Now I’m well out of my depth.)
          I’d guess someone knowledgeable could work out the relative changes in volume and pressure for a given temperature change. What I’ve observed in weather data is that
          pressure and temperature seem independent of each other – bymmv.

  19. Rosco says:

    Yes – collisions between gas molecules will increase the temperature of O2 and N2 BUT they outnumber the radiative active gases by a factor of 50 for water vapour and 2500 for CO2.

    There is little doubt in my mind that the vast majority of the air temperature is the result of conduction/convection from the heated surfaces to 99% of the atmosphere.

    How does 99% of the atmosphere lose the energy gained during daylight hours if rising to altitude is merely a transformation of kinetic energy to gravitational potential energy ? Apparently they do not radiate IR – actually they do but the bandwidth is very narrow.

    Nothing changes the fact that the energy of a photon is directly proportional to its frequency or inversely proportional to its wavelemgth – with Planck’s constant as the constant of proportionality.

    Consider what climate scientists teach as the greenhouse effect. They claim that the atmospheric “layer” of GHGs radiates back to Earth and they treat this as a continuous spectrum when they present their absurd versions of the Stefan-Boltzmann equation.

    But no gas emits a contiunuos spectrum and CO2 has three narrow bands – CO2 is at least 95% transparent to the complete range of infra-red radiation.

    Examine a Planck curve for 254 K versus 300 K – the temperatures of the radiation values taught in a typical University lecture on radiative balance for the Earth-atmosphere GHG effect.

    By simple inspection you can easily determine the number of high energy photons emitted by the surface far outnumber the number from the gases – both in photon energy and intensity of the “stream”.

    And the emissions from CO2 are in discrete wavelengths – a typical line spectrum.

    The surface may well absorb most of these photons but whether they have thermal effect varies greatly by chemical composition – but even assuming they do they are far less in both energy and intensity than what the surface is radiating over a continuous spectrum.

    I look at a Planck curve and wonder how it is possible to claim a simple sum of radiative fluxes is a legitimate application of thermodynamics – the number of high energy photons is significantly less as temperature decreases and the intensity is similarly less – if you supply less than you lose the temperature decreases and this result is what physics texts teach using the SB equation.

    Robert Brown was the main proponent of the Steel Greenhouse thermodynamics where it is claimed that inserting a radiation shield causes the object thus shielded to double its radiation output.

    I think Einstein showed this claim is BS when he explained the photoelectric effect.

    I claim all photons are not created equal and the emission of a photon does not necessarily mean the absorbing object will gain any energy from it – it may have zero effect. Einstein showed that to generate the photoeffect requires a very high energy photon and the absorption of photons by metals is an all or nothing proposition.

    The experts tell me that CO2 should have a significant absorption band at 1537 cm-1 or ~6.51 microns but it does not occur in experiment.

    The satellites record that there is actually a relatively transparent atmospheric window betwee 8 and 14 microns and that GHGs do not interfere with this radiation. This covers the peak emission for objects from 89 degrees C (6 micron) to about minus 66 degrees C – this kinda covers almost all the ambient temperatures found on Earth.

    If this is not true how did Landsat 7 record the 70.7 degree C record temperature of the Lut desert sand – this was the hottest place recorded on Earth for many years and 70.7 is the current record!

    I regularly see NASA claim something like “CO2 traps heat in the lower troposphere – less heat radiates to space and Earth is warmer”. Then they produce graphs of the radiation anomaly recorded by Nimbus over the period 1979 to 2005 and the anomaly is positive which completely disproves their claim about LESS heat radiating to space – the damn satellite detected MORE !

    I prefer Einstein, Planck and Bohr to Robert Brown anyday.

    • geran says:

      “I prefer Einstein, Planck and Bohr to Robert Brown anyday.’

      Yes, of course we all do. Einstein, Planck and Bohr were 100% real scientists. Brown is limited by his connection with academia. I suspect if he were not tethered, he would be about 95%. He does know his science, but he will not cross the line, yet.

  20. Jl says:

    “A cloudy night will feel much warmer than a clear night at the same temperature.” Confusing to me, but maybe you’re talking about something else, so bear with me. Wouldn’t it be “a cloudy night will feel warmer than a clear night because, well, it is warmer because of the clouds?” A clear, cold winter night with no clouds-the temperature drops to “x” degrees. Now, in the middle of the night a cloud cover comes in. The temperature doesn’t, or would not, drop the same number of degrees. It feels warmer, because all things being equal, it is warmer (or, it didn’t get as cold)

    • NancyG22 says:

      “Wouldn’t it be “a cloudy night will feel warmer than a clear night because, well, it is warmer because of the clouds?””

      No, at the same temperature the moister climate feels warmer. I live in a humid area. The weather forecaster will often say it’s 80 degrees but feels like 90 because of the humidity. I think it has to do with our body not being able to lose heat easily in the humid climate but I don’t know for sure. Someone here can explain that better I’m sure.

      Another example, in the winter when I set my thermostat to 70 degrees the house can feel chilly if it’s very cold out, and the humidity level is low inside and outside. My thermostat kicks on frequently to keep the house at 70. However, when I run my cold water humidifier and raise the humidity inside the house feels warmer even though it’s still set at 70 and the thermostat kicks on less frequently.

      • It has nothing to do with humidity. High clouds do exactly the same thing on a night at -15C

      • TGT says:

        In humid air net evaporation from a surface is less than in dry air. The human body does a lot of temperature regulation through evaporative cooling. Humid air reduces the efficiency.

        When sweat evaporates instantly, it carries the heat from you into the air. When it runs down inside your collar, it moves that heat to a different portion of your surface.

  21. higley7 says:

    A greenhouse prevents convectional movement of heat. That has nothing in common with a cloudy night. On a clear night the temperature differential between the land and space is 300 K versus 3 K, respectively. Clearly, the air and land shed IR (LW) rapidly to space and cool down. Greenhouse gases contribute to converting heat energy in the air to IR to be lost to space.

    On a cloudy night, the temperature differential is 300 K versus 258 K. The land radiates at its temperature at the clouds, losing energy and heating the clouds, but the clouds emit IR at their temperature downward, to be outright reflected or refilling just vacated IR energy levels of the ground. The result is that the land simply cools more slowly, as the temperature differential is two orders of magnitude less than on a clear night.

    This is thermodynamics, clouds simply slow down the cooling rate. It has nothing to do with greenhouses or convection or non-existent greenhouse gases. Period.

  22. rishrac says:

    The key here is how it feels. Yesterday ( for real ) it was 92 F, today it 51 F all day, when it was minus 18 F , and it warmed up to 40 F it felt warm. Today, it feels cold, and it is cloudy. So sunny clear days feel warmer at the same temperature.

    Excellent discussion on co2… mostly splitting hairs on whether co2 is contributing to global warming. ( or the lack of it) . I am surprised that nobody from the AGW community hasn’t come over to tell us how wrong we are. I remember a discussion on thunderstorms, that within a matter of minutes temperatures could drop by 20 or 30 F. Of course they didn’t seem to understand convection and down drafts. (colder air replacing the warm air as it rose. This all had to do with the release of latent heat from the water vapor. They say it is retained i.e. co2. I have to look at that and think down dwelling radiation from 25k to 50k ft. ? Really? Then they used the net energy inflow and outflow that supposedly proved their point. Since the ‘pause’ has happened, I haven’t seen it anywhere or any new information on it. I see heat release it in 2 actions, one is mechanical the heat is literally lifted up and released , and the second is the release of heat from water vapor. I can’t see that heat getting reflected or absorbed by co2 at temperatures that freeze water into hailstones. So since we have been putting a great deal of co2 in the atmosphere and the net amount of heat was suppose to keep increasing, I wonder why I haven’t seen any numbers on the net amount of heat. So what do you think happened? Either the incoming has decreased, which would be in direct opposition to TSI being constant, the outgoing increased, how could that happen? or nothing changed in the face of higher levels of co2. It is a mystery. I can see a nightmare for the IPCC, the incoming decreased and outgoing increased. There goes your warming world. No wonder they are being very quite about it.

  23. Tel says:

    Cloud will block (and reflect) upwelling LW radiation and thus slow the rate at which the surface cools at night. In dry desert conditions with clear sky you can have scorching hot sand during the day, but rapidly drop below zero as soon as the sun goes away. This rapid cooling does not happen with night time clouds.

    However, daytime couds ALSO BLOCK the sun that would warm the surface during the day. Thus, with a cold wet morning, and clouds during the day you won’t hit much of a maximum temperature that day.

    There’s also one more effect, which is to note that if you live in a cold climate, the clouds you see mostly did not come from local evaporation (i.e. there isn’t much evaporation in cold places). Those clouds carry energy as latent heat of water, and the energy has been transported away from warmer regions, toward colder regions. Thus, some of that downwelling LW radiation is heat that started out in Florida or the Bahamas (at the same time the cloud radiates upward to throw some of the heat away into outer space). This sideways transport of heat is good for the warmer regions (it keeps them cool) and also good for the cooler regions, and it provides rain as well. This is the effect that actually makes the world a comfortable place to live.

    • Gail Combs says:

      Water has multiple effects:
      1. Latent heat of vaporization/sublimation moves energy from the surface to high in the atmosphere.

      2. Clouds/albedo reflect energy

      3. Water vapor “closes” part of the IR window. This does not happen when humidity is zero or close to it. So deserts can radiate over a wider spectrum and therefore cool a heck of a lot faster. This is also seen on cold dry nights outside the desert.

      ….Most remote sensing is conducted above the Earth either within or above the atmosphere. The gases in the atmosphere interact with solar irradiation and with radiation from the Earth’s surface. The atmosphere itself is excited by EMR so as to become another source of released photons. Here is a generalized diagram showing relative atmospheric radiation transmission of different wavelengths. Blue zones mark minimal passage of incoming and/or outgoing radiation, whereas, white areas denote atmospheric windows, in which the radiation doesn’t interact much with air molecules and hence, isn’t absorbed.
      Technical and Historical Perspectives of Remote Sensing

      http://fas.org/irp/imint/docs/rst/Intro/AtmosWindows.JPG

  24. Sleepalot says:

    “Anyone who lives in a cold climate knows that a cloudy night will feel much warmer than a clear night at the same temperature.”

    _At the same temperature_? No.

    I live in a cold climate (an av 9.5C). I have never basked in the warmth of the clouds. Cloudy nights are cold. Clear nights are colder. They _feel_ colder because they _are_ colder. The temperature falls faster and farther on clear nights.

    (If I sound bitter and twisted, it’s because I am: I lived in Cumbria for 14 years! I swear it was overcast for 18 months straight!)

  25. Gail Combs says:

    Sleepalot says:

    Edmonton Al says:
    DK… Does a gas in an open system expand when it is heated?
    A greenhouse is a closed system. The atmosphere is an open system.
    A gas in a closed system [greenhouse] heats up because the volume stays the same.
    In an open system[atmosphere] the gas expands when heated and rises .
    It is a coolant

    That’s a tricky one. A greenhouse has a base, sides and a roof. The atmosphere has a base – the land/sea surface: it needs no sides, because it’s spherical – the air is constrained, laterally, by itself: the atmosphere has no roof, but is constrained by gravity.…..

    >>>>>>>>>>>>>>>>>>>>
    Edmonton Al is correct. The atmosphere is an open system.

    Back to my library of links {:>D

    NASA Quiet Sun Means Cooling of Earth’s Upper Atmosphere
    December 17, 2009
    New measurements from a NASA satellite show a dramatic cooling in the upper atmosphere that correlates with the declining phase of the current solar cycle. For the first time, researchers can show a timely link between the Sun and the climate of Earth’s thermosphere….

    “The Sun is in a very unusual period,” said Marty Mlynczak, SABER associate principal investigator and senior research scientist at NASA Langley. “The Earth’s thermosphere is responding remarkably – up to an order of magnitude decrease in infrared emission/radiative cooling by some molecules.”

    The TIMED measurements show a decrease in the amount of ultraviolet radiation emitted by the Sun. In addition, the amount of infrared radiation emitted from the upper atmosphere by nitric oxide molecules has decreased by nearly a factor of 10 since early 2002. These observations imply that the upper atmosphere has cooled substantially since then.

    ….a fundamental prediction of climate change theory is that the upper atmosphere will cool in response to increasing carbon dioxide. As the atmosphere cools the density will decrease, which ultimately may impact satellite operations through decreased drag over time…..

    So NASA lets slip the fact that CO2 in the upper atmosphereacts as a coolant. The same place DR Brown’s comment suggest that radiation dominates collision as the energy transfer mechanism.

    NASA Deep Solar Minimum
    April 1, 2009
    The sunspot cycle is behaving a little like the stock market. Just when you think it has hit bottom, it goes even lower….
    “This is the quietest sun we’ve seen in almost a century,” agrees sunspot expert David Hathaway….

    Careful measurements by several NASA spacecraft show that the sun’s brightness has dropped by 0.02% at visible wavelengths and 6% at extreme UV wavelengths since the solar minimum of 1996. The changes so far are not enough to reverse the course of global warming, but there are some other significant side-effects: Earth’s upper atmosphere is heated less by the sun and it is therefore less “puffed up.” ….
    science(DOT)nasa.gov/science-news/science-at-nasa/2009/01apr_deepsolarminimum/

    “Earth’s upper atmosphere is heated less by the sun and it is therefore less “puffed up.” …. So direct observation shows the earths atmosphere is free to expand in response to the amount of energy.

    If you want a ‘pee-reviewed’ version instead of NASA pop science version:

    Behaviour of the low-latitude ionosphere-plasmasphere system at long deep solar minimum

    A number of interesting observations has been reported covering the unusual solar minimum. The thermosphere contracted to record low levels.…
    …The ionosphere also contracted to extremely low levels. Using the C/NOFS data Heelis et al. showed that the ionosphere contracted to a thin shell, with the O / H transition height and ion temperature reaching record low values..
    ..satellites also showed the ionosphere contracting by 50% in 2008 and by more than 60% in 2009 as compared to IRI2007 (International Reference Ionosphere) predictions….

    ..Tides and waves found their way to the thermosphere and ionosphere more easily in the 23/24 solar minimum than in previous mimima. The diurnal pattern of the vertical ExB drift velocity observed by the C/NOFS satellite shows downward drifts in the afternoon and upward drifts near midnight at some equatorial locations instead of the usual upward drifts during daytime and downward drifts at night…..

    This Uppsala Dissertation shows the molecules are even free to completely leave earth’s gravity well.

    Low-Energy Ion Escape from the Terrestrial Polar Regions
    ABSTRACT
    The contemporary terrestrial atmosphere loses mater at a rate of 100,000tons per year. A majorfraction of the net loss is constituted by ions mainly H+ and O+ which escape from the Earth’s ionosphere in the polar regions….

    …The foot points of the magnetic field lines create a convection pattern (red) in the high-latitude ionosphere. As a result, an electric field (blue) is built up. The convection pattern follows equipotential contours of the polar cap electric field

    Figure 2.6 of polar electric fields that look like double polar vortex..

    ? is referred to as the cross-polar cap potential. Equipotential contours of this potential are perpendicular to both the electric and magnetic fields, which means that the convection flow will be along these contours. In the polar cap proper the electric field is directed towards dusk, while it is directed towards dawn in the auroral region (see Figure 2.6(a))…..

    The polar wind is mainly varying with solar UV flux, since it controls the ionization rate and photoelectron production in the ionosphere. Therefore the polar wind is sometimes referred to as photothermal outflow (Moore and Horwitz, 2007). The auroral outflows, on the other hand, are enhanced during active times, when the solar wind-ionospheric coupling is strong. Since the
    solar wind energy input shows larger variability than the solar radiation, the auroral wind is much more variable than the polar wind. Nsumei et al. (2008) have shown that solar illumination controls the plasma density over the polar caps mainly at low altitudes (below 2.5 RE), whereas it is controlled by the geomagnetic activity at higher altitudes (above 4 RE)….

    • Sleepalot says:

      Hello Gail, 🙂
      “Edmonton Al is correct. The atmosphere is an open system.”
      Then whence cometh variations in sea-level air pressure?

      NASA said: “As the atmosphere cools the density will decrease,(…)”
      That’s not right, is it?

      (Sorry, I haven’t read right through – it may take me some time. 🙁

    • Sleepalot says:

      ““Earth’s upper atmosphere is heated less by the sun and it is therefore less “puffed up.” …. So direct observation shows the earths atmosphere is free to expand in response to the amount of energy.”

      I expand (I breathe in) – but not *freely* – my lungs are constrained by ribs and skin and stuff.

      Yes, I accept the atmosphere expands: aiui, more at the equator than the poles, but I doubt that it’s free, (gave my thoughts previously) and suspect that sea-level air-pressure differences result from that constraint.

      “This Uppsala Dissertation shows the molecules are even free to completely leave earth’s gravity well.”

      Aiui, only H and He can achieve escape velocity. O is too heavy: but I can’t argue that.

      • Gail Combs says:

        “…A major fraction of the net loss is constituted by ions mainly H+ and O+ which escape from the Earth’s ionosphere in the polar regions….”

        Seems Oxygen can also escape earth’s gravity well.

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