Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Earthward Upper Stratospheric IR Radiation Cancels Most Greenhouse Gas Effect

  1. Oct 5, 2008 #1
    Atmospheric gases play a role in planetary temperature regulation Carbon dioxide levels have been rising rapidly in the Earth’s atmosphere and are linked by the IPCC to “global” warming. Recent failure of measured temperatures to advance with increasing carbon dioxide has called this assertion into question. Part of the problem has come from the term absorption. The coupling of a photon with an atmospheric gas molecule is better described as a liaison, a brief union that ends with the directionally random (Lambertian) dissociation of the photon. No atmospheric energy is added. The dry, dust-free troposphere remains adiabatic. The photon is simply redirected. Effects on temperature depend on the change in direction of the liaison photon. The model used by climatologists commonly assumes that all photons involved in the radiation balance originate from the Earth’s surface and are deflected back to the Earth, causing warming. But people from the same general discipline who are focused on stratospheric gases and their concentrations recognize that radiation from the stratosphere itself is also based on the same fourth power of temperature.
    http://www.atmos-chem-phys-discuss.net/7/11561/2007/acpd-7-11561-2007-print.pdf They use GENSPECT to analyze the stratospheric chemical levels assuming black body emissivity. Other models like MODTRAN fail to incorporate stratospheric downward thermal radiation. Downward photons arising from the warm upper stratosphere are affected oppositely by the liaison process and sent into space by scattering, counteracting the effect of the same gas on upward radiation. Overall loss is much less influenced by greenhouse gas concentration than IPCC models indicate. This is why Earth’s temperature is not rising as predicted.

    An important modeling need is knowledge of emissivity. Black body means an emissivity of 1.0. Stefan used this value in calculating the temperature of the Sun not long after his 1879 paper. Stratospheric chemical analysts using infrared also make this assumption to at least 35 km altitude. Many experimentalists have generated tables of values for a broad array of materials http://www.omega.com/literature/transactions/volume1/emissivity.html http://www.engineeringtoolbox.com/emissivity-coefficients-d_447.html Most values are below 1.0, some fairly strikingly. Some Earth surface outward radiation models use experimental numbers rather than 1.0 http://www.gisdevelopment.net/technology/rs/ma03196.htm .

    Emissivity is not always near 1.0. In the solar system, the Sun’s corona has an emissivity on the order of 10-10. Its very low density limits its radiation intensity. Beyond this example, we know little about the effect of density on emissivity. But if the emissivity of the Earth’s thermosphere is more than 10-4 all current Earth radiation balance models are seriously erroneous. By the way, the 50 km top of the stratosphere has a mass density the same as the Sun’s photosphere. http://en.wikipedia.org/wiki/Earth's_atmosphere http://www.madsci.org/posts/archives/2001-05/988762969.As.r.html

    The need to link emissivity to density is clear. Emissivity must fall somewhere above the top of the stratosphere. There is an unusual reward for this new understanding. Density may be expressed as mass or atoms/molecules per unit volume. Planck-Stefan-Boltzmann radiation is a basic property of matter. All matter above absolute zero radiates photons to the universe if they can find their way. Is this a consequence of mass or existence?
  2. jcsd
  3. Oct 24, 2008 #2
    No-one has replied to this posting. I understand that this reflects strong burnout on the AGW issue. This is seen by going back several years through AGW-linked threads. More heat than light. But there are two points I would like to add before this thread finds its way into the PF time-mediated dustbin.

    Andre http://met.hu/doc/idojaras/vol111001_01.pdf called to my attention the Miskolczi 2007 greenhouse gas heating-opposing paper https://www.physicsforums.com/showthread.php?t=232818 He also cited this Miskolczi co-authored 2002 paper. http://smsc.cnes.fr/documentation/IASI/Publications/LBL_EX.pdf It focuses on modeling using available downward IR radiation (ARM) to compare two major line by line models (GENSL2 from Boulder and HARTCODE from Trieste) being used in radiation balance analysis. Like MODTRAN but not GENSPECT they use balancing gray body emissivity combined with optical depth to obtain radiation balance. Miskolczi’s 2007 paper contains an elaborate defense of this approach in the text and appendix B and still indicates that a doubling of atmospheric CO2 will raise Earth’s temperature only 0.24 oK. These models are unacceptably flawed and should be abandoned. The gray-depth combination underestimates optical depth and abrogates atmospheric radiation. Liaisons that send photons back to Earth are called absorption and equated with downward emissivity. Other liaisons are ignored. The CO2 conclusion is reached without any true downward air thermal emission by using rotating water vapor stabilization.

    The model I presented was rather barren and deserves a little fleshing out. The upper stratosphere is warmed by solar UV-driven chemical reactions. This makes upper stratospheric temperature sensitive to season, latitude and ozone level. Ozone reduction has been more prominent in the Northern hemisphere and is well measured. Seasonal variation is also well recorded (see 1,2 hPa) http://www.cpc.noaa.gov/products/stratosphere/temperature/ Temperature and pressure information is generated in the four above named programs in order to use HITRAN with Lorentzian and Voit adjustments but not for emissivity in three. A careful review of the criticisms of the Curtis-Godson method that is used and the seasonal patterns shown by NOAA should demonstrate that no current model satisfies radiation balance needs. Upper stratospheric temperatures can exceed ground temperatures above 60 degrees latitude, especially in the South. This means that greenhouse gases can cool rather than warm many areas during some times of the year. Calculated atmospheric temperatures must be compared with observed values in validating models. Appropriate altitude/density choices should allow an effective atmospheric emissivity model to be developed. Clouds have deliberately been avoided in the above treatments but will become susceptible in an emissivity model.

    I hope that someone will at least indicate that they read and understood what is being said here.
  4. Oct 24, 2008 #3


    User Avatar
    Gold Member

    It means nothing, but i do read all your posts with interest and can understand a lot of what you wright, i sure hope you keep us in touch.
  5. Oct 24, 2008 #4
    Perhaps it's also because of the objective of the post is somewhat obscured as some steps may be too large to follow. For instance:

    I guess this is a bridge too far.

    However after Chilingar et al in the other thread the insight in greenhouse effect, especially the IR emission at higher altitudes should also contribute to the doubt about the original suppositions. Furthermore there is this submitted article of Roy Spencer reflecting on the general pictures, including clouds.
  6. Oct 24, 2008 #5


    User Avatar
    Gold Member

    Why was AGW bought up in the first place? It seems to me that this is another gravy train,
    no one will ever prove it one way or the other in this century, it seems all one can say is global warming has happened in the past with or with out human intervention.
    Ice cores or what ever pre human evidence is absent of human activity, so it is null and void,
    all it proves is that temperatures (can) rise without humans present.
    In other words prove that carbon emitting humans are changing the atmosphere in (our) history.
  7. Oct 25, 2008 #6
    I thank Wolram and Andre for their attention. I used AGW as shorthand for the IPCC position used to introduce the thread. I am optimistic after recently discerning gray-shift model problems that their replacement by atmospheric radiation models will allow us to match MSU data much more closely. It is ironic that clear sky models were tested on data collected to quantify cloud behavior (ARM). A simple addition of black body upper stratosphere radiation in both directions clears up a lot of old problems. Warming is regionalized and its recent reversal explained. Clouds experience nocturnal warming from above and below. Greenhouse gas effects become thrall to solar 242 nm UV levels. Human and solar contributions may be scaled and adjusted for. The polar bear and narwhal are saved by CFC control.

    I was trying to contrast the two approaches to handling of atmospheric radiation. I had not yet come to appreciate fully the ablation performed by the gray body maneuver in the climate models. Use of black body emissivity is supported by the chemical analysis application. Its avoidance is not supportable. Your phrase is a little painful to someone my age. I associate that movie with the Dutch famine near the end of WWII.

    Your mention of Chilingar et al took me a little time. Here I will only say that convection and radiation have the same complex relationship that they have near the surface of the Sun. In the end, only radiation finds its way into space. Its balance is necessary and sufficient to warm and cool the Earth. I had thought seriously of posting a comment focused on atmospheric convective processes before and will post it on the cooling thread you started in a few days.

    Andre, you read widely and have called many interesting documents to my attention. You may have already seen the two I cite now. http://books.google.com/books?id=8n...a=X&oi=book_result&resnum=4&ct=result#PPA1,M1 develops the solar convection-radiation photosphere model effectively. I found it while looking for useful approaches to Earth’s problems. http://www.atm.ox.ac.uk/user/irwin/radlectures/Radiation.pdf supported the gray-depth flaw but argued effectively for sensitivity of the Earth’s temperature to radiation balance.
  8. Oct 26, 2008 #7
    I believe that this may also be of importance, the vertical diurnal (daily) temperature variations



    It can be observed that the daily variation at higher altitude is around 2-4K whilst at the surface it's around 20K. We knew that already but failed to see the significance. During the night the Earth surface cools the strongest (by out radiation) and this interact with the lowest levels of the atmosphere, less than 2000 ft, causing an inversion. Why would only this lowest layer cool? Why aren't the temperature plots just shifting to the left, cooling uniformly? Obviously it needs the Earth surface to cool, but by what mechanism? Conduction or/and radiation? Obviously not convection. How would this relate to the GHG hypothesis?

    Incidently I notice that the radiation study also does not mention convection as heat exchange mechanism.

    Also the green plot shows that the warming of the atmosphere at day break starts at the surface.
  9. Oct 29, 2008 #8
    Andre, you regularly manage to distract me from my planned direction. Your points about the Houston atmosphere are subtle and well targeted. Many years ago, a satellite picture showed an Eastern comma of white opacity when Houston was photographed. This meaty graph shows that even at low height (0.5-0.6 km) an inversion can change the rules. The haze/fog generates heat with condensation and then assimilates radiant heat during Mie mostly IR scattering from above and below. The layer at the top with the highest temperature radiates Planck-Stefan-Boltzmann IR in all directions. By radiating nearly half downward into the greenhouse gases below it causes some radiation to be lost into space when scattered. All atmospheric downward radiation reverses the modeled greenhouse gas effect. Surface heat is lost by local evaporation. The surface temperature underestimates FU by 5-8% and greenhouse effect is overestimated by a few more percent. Such inversions probably cover some of the ocean at night. We will have to await more flights. I will add another model critique shortly.
  10. Oct 31, 2008 #9
    I pointed out the deficiencies of GENLN2 and HARTCODE in handling atmospheric emissivity. The most influential model over time has been the GISS model. I set out to look at it in the same way. It is older, more complex, and multi-tasked than the first two. Its design is targeted at climate tracking with an eye to prediction. It was used in 1988 to predict future temperature rise in 3 possible paths in US Congressional testimony http://www.columbia.edu/~jeh1/2005/Crichton_20050927.pdf . It is woven into IPCC thinking and actions. By 2005 it was in stage III, version 5. The overall model uses latitude and longitude in progressively smaller intervals and earlier 9 and now 20 vertical layers. Actual information about temperature and other variables are put in, including at the surface. These are used in outgoing IR calculations. Diurnal changes in surface temperature are used in calculations. Additionally, the emissivity of water bodies is affected by wind speed and land emissivity altered by snow and ice. Both short and long wave absorption and scattering are handled by a κ -distribution technique that recognizes pressure effects on photon interactions. Cloud and haze effects are treated using particle size-handling techniques.

    page 620 http://pubs.giss.nasa.gov/docs/1983/1983_Hansen_etal.pdf

    The major question is linked to gray body and optical depth use. In this case, each layer receives a gray body Planck function adjustment based on optical depth to that layer. No numbers are supplied. This means that there is a general similarity in all 3 approaches in which the atmosphere is treated as non-radiative except for cloud radiation in this case. The other two approaches excluded clouds from their analysis. Clouds raise optical depth and have some effect by this means. This approach, like most others, avoids the downward distribution effect of atmospheric Stefan-Boltzmann radiation.

    One of the tests commonly used to scale the greenhouse problem is the effect of a doubling of CO2 on global temperature. In 1988, the GISS value was 4.8 oK and 3 oK in early 2005 http://www.columbia.edu/~jeh1/2005/Crichton_20050927.pdf . The GISS model fell to 1.96+0.02 oK in late 2005. http://pubs.giss.nasa.gov/docs/2005/2005_Hansen_etal_2.pdf Determinations were made by the model in motion with real data. Andre used MODTRAN and CO2 doubling to calculate a 3.2 W m-2 suppression that I believe corresponds to 1.39 oK rise. HARTCODE has generated two numbers that are much lower, 0.48 oK http://hps.elte.hu/zagoni/idojaras2004_Vol108_No4.pdf and 0.24 oK http://met.hu/doc/idojaras/vol111001_01.pdf 2006/7 . The reason for this shift is not given, but a satisfactory explanation for the substantial overall difference is needed. In the meanwhile a simple two layer average temperature model using 14 oC for surface temperature and -11 oC for the upper stratosphere temperature http://www.cpc.noaa.gov/products/stratosphere/temperature/ argues that downward radiation should be 69% of upward radiation reducing all of these numbers by over threefold. If CO2 doubling’s effect is reduced to 0.65 oK or less by downward stratospheric IR radiation, it is clear that 1979-2008 14% CO2 increase http://en.wikipedia.org/wiki/Keeling_Curve is not responsible for much of the MSU LT rise of 0.393 oK seen over the last 29.5 years. Stratospheric cooling due to ozone loss is probably more important and explains the Northern regional prominence of the rise.

    Hansen has worked hard over many years to develop a model to predict future weather. It has not been successful. He has been led astray by preoccupation with the Revelle-Seuss 1957 CO2 proposal. The radiative modeling design failure has led him to overestimate greenhouse effects. Weather-climate modeling will not be taken seriously until it can predict ENSO events before the beginning of December. Revision of the radiative model and incorporation of solar magnetic events into it could lead to ENSO prediction and scientific status for climatology. Until then it should act like a developing science, not a mal-targeted political movement.
    Last edited: Oct 31, 2008
  11. Oct 31, 2008 #10
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Have something to add?

Similar Discussions: Earthward Upper Stratospheric IR Radiation Cancels Most Greenhouse Gas Effect