[ancient_geezer]

Hug's work is controversial and has yet to be assessed by the climate community. It essentially constitutes a lower-bound if it's correct.

So was Galileo's work.

Hug's work is a direct assessment of the actual IR absorption on which the CO₂ greenhouse sensitivity depends. One experiment is worth a million words of controversy. Hug did the experiment, the CGM modelers and IPCC have offered only theoretical speculation as to what CO₂ IR absorption ought to be under ideal (i.e. H₂O free) conditions. Hug's result in the presense of H₂0 has established reality can be substantially different from the ideal speculations by up to 2 orders of magnitude. The global warming(i.e. IPCC etc.) folks have yet to provide any experimental evidence they are correct in their speculative assumptions nor do they in anyway controvert Hug's results.

Here is a summary Hug's response to the GW community's, 100's of "scientists" in regards IR absorption and other objections.

Hug & Barret,
DECHEMA colloquium, Frankfurt on 11^th Oct, 2001

"An estimated global warming range of 2.5–10.4°F was announced earlier this year by the Intergovernmental Panel on Climate Change (IPCC)"

Problem is IPCC depends on the CGMs and the assumptions inherent in them, which are very clearly flawed and incomplete. Other estimates based in emperical and theretical concerns, not just IPCC's CGMs, range from 1.4^oC(2.5_oF) downward. With historical 100yr variability studies indicating a range of +1.4^oC(2.5^oF) upper probability(1s) boundry and -1.0^oC(1s) lower boundry.

Frankly, as I have said, there very well be be a degree of warming going on. But the state of knowledge in atmospheric science, especially as regards the full roles of water vapor in the atmosphere, does not allow anyone to make predictions for the next 30days much less 100 yrs.

The UCAR pictorial of probability, is nothing more than a reflection of IPCC model variablility and does not reflect the natural variability of the real world, only the GW apriori assumptions that anthropogenic changes in GHG concentrations must cause substantive upward temperature change.

"New estimates of sulfur dioxide and other emissions, along with updated information on carbon storage, ocean circulation, radiation, and other components of the earth system have improved computer models of the earth's climate and led the IPCC to both raise and widen its estimated range of global temperature increase. The latest range of 2.5-10.4°F is up significantly from the panel's 1995 estimates of 1.4–6.3°."

This just a repeat of the same model outputs over again in another form, no indication they have impoved there water vapor models, which they have not done.

I repeat, others using both theoretical and empirical studies come up with an entirely different set of projections ranging downward from the IPCC low.

I find it interesting that out of all the range provided, the GW folks never present or even apparently consider the possibility that global climate temperatures can fall as well as rise. This is a telling note. They appear to be totally dedicated to demonstrating rising global temperture inspite of historical evidence that climates tempertures make excursions downward even with atmospheric CO₂ concentrations much higher than even those assumed doublings of IPCCs GCM story lines.

[cogitator]

I was concerned enough about Hug's results to do a Web search. One, I wish to withdraw my objection with regard to community review. Both Barrett and Hug have published on this matter. Barrett published in Spectrochimica Acta (see below) and Hug has published in German journals. I found this summary of a reply to Barrett's published paper (which is the genesis of Hug's work). The words below the reference are not mine.

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"Comment on "The roles of carbon dioxide and water vapour in warming and cooling the Earth's troposphere" " John Houghton Spectrochimica Acta v.51A, p.1391-1392 ( 1995 )

Sir John very politely, and carefully points out the problems, and goes on to explain that as the concentration of CO2 in the atmosphere increases, so too does the average height (about 6km) from which CO2 emits radiation in space. Since atmospheric temperature in the lower atmosphere falls with altitude, if nothing changes other than the amount of CO2, the amount of radiation to space is reduced. For atmospheric CO2, this reduction is about 4Wm^-2. To restore the Earth's energy balance the temperature thoughout the lower atmosphere has to increase - hence the enhanced greenhouse effect.

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That's where the argument rests. My time is limited, but I also admit that it would be impossible for me to go into any greater detail about Hug and Barrett's results. Apparently there are lengthy "Open Reviews" on Daly's Web site, for anyone that really wants to dive in.

I find it interesting that out of all the range provided, the GW folks never present or even apparently consider the possibility that global climate temperatures can fall as well as rise. This is a telling note. They appear to be totally dedicated to demonstrating rising global temperture inspite of historical evidence that climates tempertures make excursions downward even with atmospheric CO2 concentrations much higher than even those assumed doublings of IPCCs GCM story lines.

But you need a mechanism for cooling. The only one that I can think of is volcanism (sulfur aerosols, as demonstrated by El Chichon and Mt. Pinatubo). What else could occur that would result in cooling? (It now occurs to me that there has been some question about the sign of forcing for black soot aerosols, i.e., do they shade more = cooling, or do they absorb more = warming? Hansen thinks that absorption outweighs shading.

Sorry that I can't continue for about 12 days. Not to be mysterious about it, I'm going on vacation.