On the battle between Arrhenius and Ångström.
Story submitted by John Kehr, The Inconvenient Skeptic
Any serious discussion about the Theory of Global Warming will eventually include the absorption band argument that started more than 100 years ago between Arrhenius and Ångström. One of the arguments presented by Ångström was that the main CO2 absorption band is between 14-16 micron and that band is also absorbed by water vapor (which is correct). The counter to this by Arrhenius was that it didn’t matter in the upper atmosphere where there was no water vapor. Of course none of this matters because radiative heat transfer is only 20% of the energy transferred to the atmosphere, but that is generally ignored by both sides of the argument.
At the time there was no way to measure the temperature in the upper atmosphere so there was no way to determine what was going on there, but of course now there are many ways to measure the temperature there. When I started looking at the annual temperature behavior of the stratosphere and the top of the troposphere I found something very interesting that is as usual, bad for the warmists.
Here is the average daily temperature of the troposphere (at ~4.2 km) and the stratosphere (41 km).
What makes this so interesting is that they are completely out of phase with each other.
The tropospheric temperature is matched to the natural global temperature cycle. This is highly dependent on the geography of the Earth’s surface. The stratospheric temperature is not in phase at all with the surface temperature. It is however in phase with the Earth’s orbit around the Sun. The distance the Earth is from the Sun determines how much energy the Earth gets from the Sun. Here is the stratospheric temperature and the solar constant over the course of the year.
While I would not say that the upper atmospheric temperature is completely independent, it is mostly independent of the of the lower atmosphere. The cooling in the stratosphere each spring is exactly what would be expected based on the changing solar constant. The warming that takes place in July is likely caused by the peak atmospheric temperatures in the NH that take place during the summer months. That warming stops in October, but by that point the increasing solar iconstant warms the stratosphere.
What determines the stratospheric temperature is absolutely critical to understanding why it has been cooling over the past 60 years (which is about how long it’s temperature has been measured). If the stratosphere’s temperature is primarily dictated by the incoming solar energy then the argument made by Arrhenius is meaningless. That is because the increase in CO2 would never have an impact on the temperature there, simply because so little of the energy needed to warm the stratosphere comes from the Earth’s surface.
Based on the scientific data, the stratosphere is mostly influenced by the solar constant (basically the distance from the Sun for this discussion). There appears to be some influence from the lower atmosphere, but it is clearly marginal. This is not really a surprise since the energy transfer mechanisms are very limited above 12km. The low atmospheric density results in low vertical mixing rates which only leaves radiative transfer which is a poor method for heat transfer when low absolute temperatures are involved.
When the temperature of the stratosphere and the troposphere are compared for the period from 2003-2011 it is also interesting to note that the peak stratospheric temperature was lowest of the whole period in early 2009. This also matches the period of minimal solar activity over the entire period of time. All of these pieces together clearly demonstrate the importance of the solar constant on the stratospheric temperature. This also means that any impact by atmospheric CO2 levels on the stratospheric temperatures is very limited.
Total Solar Insolation
The argument is made time and time again that CO2 warms the planet by reducing outgoing radiation, requiring an increase in surface temperatures to restore the radiative balance. This ignores the effect to conduction and convection.
As the surface warms at the equator in daytime, energy is conducted to the N2/O2 molecules at the surface. This is energy that in the absence of N2/O2 would have been radiated back to space. The N2/O2 are non radiating, so the net effect must be a reduction in the radiation to space.
This reduction in outgoing radiation by N2/O2 is no different than the reduction in outgoing radiation by CO2 that is predicted to cause global warming. If CO2 warms the planet by reducing outgoing radiation, then so must O2/N2.
The energy in the N2/O2 will either be radiated to space by conduction to CO2, reducing the net temperature of the planet, or be returned by convection/conduction to the nighttime and polar regions of the surface, warming the surface. This return of energy to the surface by N2/O2 is no different than the return of CO2 via back radiation.
Thus we see that N2/O2 via the process of conduction and convection provides the same mechanism to move energy and increase the surface temperatures as predicted for CO2.
Phil says:
April 30, 2012 at 7:28 pm
It all starts with magnetism.
Exactly what Leif’s diagrams were showing the other day. The warming in the arctic correlates with the movement of the north magnetic pole TOWARDS the north geographic pole. While at the same time the cooling in the antarctic correlates with the movement of the south magnetic pole AWAY from the south geographic pole.
We know that the solar wind enters the atmosphere at the magnetic poles. This is a massive amount of energy entering the atmosphere in the form of charged particles. It will of necessity affect atmospheric chemistry such as ozone production, cloud seeding (particle clumping) rates, etc. Completely ignored by climate science and the climate models in their obsession with CO2.
http://www.sciencedirect.com/science/article/pii/0273117783902065
Abstract
The dissipation of solar wind energy makes an important contribution to the energy budget of the earth’s upper atmosphere. Heating and momentum transfer by this energy source generate a permanent disturbance zone in the polar region which is characterized by an increase in the temperature and pressure, strong vertical and horizontal winds, and significant changes in the density structure.
Highly interesting. The divergence between tropospheric and stratospheric temperature has great significance for interpreting volcanic cooling. I have demonstrated that volcanic cooling does not exist even though the stratosphere cools measurably about two years after an eruption. As far as I can tell, that cooling never reaches ground level despite all the temperature graphs coming out of IPCC. Seeing that the two temperatures are almost completely decoupled explains why. But how about that Pinatubo cooling that Roy Spencer shows on his web site? Very simple. He does not understand his own data. That cooling is just a La Nina cooling mislabeled as Pinatubo cooling. All so-called volcanic cooling incidents within the last century are La Nina cooling incidents that have been wrongly appropriated as volcanic cooling. It depends on the relative timing of the eruption with respect to a La Nina. If a La Nina follows an eruption it is appropriated for that volcano. On the other hand, if an El Nino follows an eruption we get a warm peak, no cooling, and a conundrum the vulcanologists cannot understand. This is what happened to El Chichon who got gipped out of its cooling because it picked a bad time to erupt.
I don’t have a lot of confidence here but the cooling of the stratosphere happens when the sun is over the equator heading south. This will induce maximum convective activity over the ITCZ. According to Lindzen (google Lindzen iris effect) this causes a reduction of high altitude cirrus which removes the warming effect.
Warming of the troposphere is understood to be due to land masses being concentrated in the northern hemisphere.
@KR
You are still playing the “long term trend” game, as is the paper you linked to in Figure 9. Figure 3 clearly supports what I said even after the authors threw in questionable data sources such as STAR. The stratosphere has NOT been cooling since 1995, period.
The stratosphere is greatly affected by volcanic activity, not CO2 which doesn’t even have the heat capacity to hold that much heat.
http://notrickszone.com/2010/12/19/study-shows-half-of-warming-since-1980-due-to-clean-skies/
The tropical troposphere is NOT warming as advertised in all of the 30 years of available data, so instead of acknowledging this inconvenient truth, the prognosticators of AGW prefer to look for some other source of data supporting the “theory”, such as winds or other obscure unproven measurement system.
ferd berple says:
May 1, 2012 at 6:52 am
ferd,
Who is saying “CO2 warms the planet by reducing outgoing radiation, requiring an increase in surface temperatures to restore the radiative balance.”? There is a reduction in radiation heat transfer from the surface to space due to CO2 (and clouds and water vapor, etc.), and conduction and convection and evaporation followed by condensation at latitude, but in the end, the final radiation to space is equal to the input (assuming steady state with no storage). All the CO2 and others do is raise the location of outgoing radiation, and the lapse rate does the rest.
The N2/O2 argument is real, the IPCC must treat these gases as having no overall ‘warming’ effect on the surface, which is so laughably wrong. We live in a collision dominated atmosphere. This is an issue of air pressure, atmospheric circulation, and the oceans thermal capacity/inertia. Our atmosphere’s altitude based thermal profile determined by air pressure and chemical composition to an extent.
Stratospheric temperature, in the long run, is solely determined by OZONE, ozone absorbs a considerable portion of intense solar shortwave radiation within it’s spectral bounds, heating up considerably, and conducting this heat to surrounding molecules. The more upper atmospheric ozone, the warmer the stratosphere.
So only two things can modulate the stratospheric temperature over time. Variations in the solar wind, and variations in the mechanism that repels the solar wind..the Earth’s geomagnetic field.
If you deplete ozone in the upper atmosphere, not only does more shortwave radiation enter the troposphere, but the biggie involves alterations to atmospheric circulatory mechanisms..the big guns. Ozone is a big player in the mechanism dominating kinetic flow variations such as the AO/NAO/AAO and the Hadley Cells. So with these circulation changes comes a change in global winds/terrestrial angular momentum, ENSO, cloud cover/ice cover, hence oceanic heat content, convection, etc.
So it should NOT be a surprise to ANYONE that there is a strong climactic correlation between climate and the solar wind+geomagnetism. Neither should it come as a surprise that what we know as the ‘AMO’, or ‘PDO’ tend to follow cycles incident to the solar magnetic Hale Cycle. Nor should it come as a surprise that ENSO is a lagged response product to variations in the solar wind, with the lag resulting from the internal system’s vast thermal inertia. The AO/NAO/AAO, ENSO, and solar wind show decadal scale correlations for a reason. Many people forget about the Earth’s own magnetic field when correlating climate to the solar wind..big error. Repairing this error, and allowing for the Solar Magnetic Rope (Hale) Cycle, the correlation is perfect.
Phil says:
May 1, 2012 at 12:25 pm
Stratospheric temperature, in the long run, is solely determined by OZONE, ozone absorbs a considerable portion of intense solar shortwave radiation within it’s spectral bounds, heating up considerably, and conducting this heat to surrounding molecules. The more upper atmospheric ozone, the warmer the stratosphere.
No it’s determined by Oxygen which absorbs UV and at sufficiently short wavelengths dissociates to form O atoms which can then form O3. That O3 can then absorb longer wavelength UV, however that ozone photodissociates so it doesn’t ‘heat up considerably’. O3, like CO2 in the stratosphere does cool the stratosphere by radiating to outer space (see e.g. Clough & Iacono, JGR, vol 100), it only warms the lower stratosphere (~100mbar).
Huh? First of all we’re talking about long term variation in stratospheric molecular temperature, not what sets the ‘average’, if you’d like to call it that.
In no way whatsoever does O3 cool the stratospheric molecular temperature, that is physically impossible unless collision does not exist.
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O3 contains spectral absorption potential greater than that of O2 however both are weak stellar IR emitters.
Variation occurs via the solar wind modulation of the O3 count/formation process.
It is important to understand the basic physics behind the niche and operation of stratospheric O3. In no way can it cool the stratospheric molecular temperature.
http://www.atmos.washington.edu/~houze/301/Miscellaneous/ozone.pdf
These sort of errors reside within the thinking of those who overweight the role that molecular re-radiation plays in determining molecular temperature.
To clarify, we’re discussing what determines temperature variation in the stratosphere, not the ‘average’ temperature, if there ever were such a thing.
What IR value O2 can absorb from sister molecules is meager compared to the process of diffusion.
“What determines the stratospheric temperature is absolutely critical to understanding why it has been cooling over the past 60 years ”
The lower stratosphere, at least, has not been cooling since 1994
ftp://ftp.ssmi.com/msu/graphics/tls/plots/rss_ts_channel_tls_global_land_and_sea_v03_3.png
Hopefully my multiple posts above have not wreaked havoc, apologies for the unusual image file. I’ve followed up with the ‘O3 basics’ PDF.
steve s,
Only when employing the “long term trend” meme can warmists cling to the stratosphere cooling fairytale with respect to CO2, which is what they claim after the fact is the AGW fingerprint when the truth is from the beginning of the greenhouse scare (Hansen 1988) it is the troposphere that should warm significantly faster than the surface. Without that, any reference to stratospheric “cooling”, is just psychobabble.
I certainly bought into the whole greenhouse scare story back then and kept watching for greenhouse to take effect. After nearly 1/4 century after Hansen’s Congressional testimony, none of it has come to pass.
The SH has more ocean surface than the NH. When the Solar Constant is highest the SH is receiving most of the solar radiation. The ocean surface is aborbing more of this radiation so that the troposhere is not getting as much heat. This causes the divergence between the stratosphere temp and the troposphere temp.
What I just said makes no sense. Sory about that. When the Solar Constant is highest the NH receives the most solar radiation.
What I should of said is “when the Solar Constant is highest the NH receives the most radiation, But since the NH has more land mass than the SH and this land mass is covered in snow at that time, more of this radiation is reflected into space and doesn’t warm the troposphere. This causes the divergence in temperatures between the troposphere and the stratosphere.
The solar constant is highest during the NH winter, but the differing emission properties of land/water result in a higher surface temperature during the NH summer in the face of 100W/m^2 less solar radiation. The stratospheric temperature feels relatively little effect from surface IR emission because the temperature of the molecular atmosphere has very little to due with longwave radiation, and more to do with pressure/conduction, and the resulting thermalization. Since it is conduction yet again on both levels the Ozone in the stratosphere is vital.
So again we get back into the whole solar wind+magnetism modulation of Ozone thing that I mentioned earlier..and that the other Phil misinterpreted.
I shall regurgitate..Ozone warms the stratosphere.
“Ozone warms the stratosphere.”
Which is exactly why it is so significant that recent data shows a reverse in the ozone quantity trends above and below 45Km in response to solar variability.
If the temperature of the stratosphere below 45km actually follows the ozone trend above 45km then we can get the right sign of stratospheric response to solar changes to produce the observed air circulation changes in the troposphere.
Otherwise our observations make no sense in real world physics as I have explained several times previously.
DR – “You are still playing the “long term trend” game…
We are talking about climate, are we not? Which involves long time periods? Just checking…
Gases are (whatever gas) very, very, very poor absorbers and emitters. In practice they can emit heat radiation only when temperature is well over 600C.
correct me if I’m mistaken (I have not looked lately) but I believe the north polar O3 count and trend has diverged from that of the south pole. The ‘ozone hole’ being attributed to man is another example of ignorance of solar variability.
Phil says:
May 1, 2012 at 6:04 pm
Huh? First of all we’re talking about long term variation in stratospheric molecular temperature, not what sets the ‘average’, if you’d like to call it that.
In no way whatsoever does O3 cool the stratospheric molecular temperature, that is physically impossible unless collision does not exist.
Really, perhaps you should have read the paper I cited.
O3 warms the lower stratosphere at altitudes below ~26km and cools the stratosphere above that. According to Clough it’s responsible for ~18% of upper stratospheric cooling.
As I pointed out above O3 cannot be heated by UV since it will photodissociate, the resulting O atoms and excited O2 could transfer heat to other molecules though.
The reason the sun heats the stratrosphere is that O2 absorbs UVC. O2 is ionized, creating O3 which also absorbs UVB. As UVB is narrow compared to UVC, I expect O3 plays a smaller role.
Since solar UV varies more than total solar output, does that mean UV variation affects only the stratrosphere or also surface temperatures?