In short he passed off to the IPCC view of water vapor as feedback by selective redefinition so it can be shunted aside as the overwhelmingly dominant greenhouse gas. To admit to H20 being a GHG that would be to admit to the inconsequentiality of anthropogenic CO2 as a problem.
Remember the Earth Observatory article about clouds I offered a couple of days ago? Well, the next one in the series is out. It provides a very clear description of the interaction of CO2 and water vapor. At least for this group, it's pretty obvious that water vapor is a greenhouse gas.
Does the Earth have an Iris Analog?
In particular, note the paragraphs beginning "Although carbon dioxide gets most of the bad publicity..." and "This is a terrifically important feedback," Lindzen concludes..."
So at least for Lindzen, one of the more important skeptical scientists, there's no doubting the importance of the water vapor feedback we've been discussing.
I'm not sure I understand this. Are you saying that no atmospheric molecules in the stratosphere can absorb longwave radiation?
No, I am saying the stratosphere's composition is such that water vapor is not the dominant factor of longwave absorption that it plays in the troposphere. The IR transmission window is much broader in the stratosphere, with O3 @ 10 & 15u playing the dominant role of any "longwave absorption" on very narrow absorption lines.
That is MUCH clearer now. Obviously ozone is significant in the stratosphere because ozone depletion is affecting stratospheric temperatures to an extent.
CO2 absorption above 11km is virtually nonexistant. H2O absorption is very attenuated. There is virtually no IR absorption by N2 and O2, they absorb UV radiant energy only and aquire heat from kinetic collision with IR active gasses.
OK. (I want to do a bit of research on this, but not while posting this reply.)
But until somebody reputable in the climate change community stands up and says "Ohmigod, we screwed up -- look at this paper by Hug and Barrett!", I am going to harbor my suspicion
The UN's IPCC and their modellers perhaps? I wouldn't hold my breath.
Not everybody is in the IPCC. What they need is a respected maverick: somebody who is known well enough to be influential, but someone who considers alternatives to the mainstream consensus. Not to drop names, but someone I am aware of who fits this "profile" is Raymond Pierrehumbert.
I'll continue to go along with these folks, until there is a clear and convincing demonstration of the validity the UN sponsored IPCC Global Warming bandwagon. That clear and convincing demonstration answering the counterpoints has yet to surface, and mere academic creditials bolstering yet more words in not going to do it.
Well, in that vein, I emailed Henry Pollack about some outstanding borehole temperature questions that I would like to resolve. Haven't heard back from him yet, but it has only been a day.
there's no doubting the importance of the water vapor feedback we've been discussing.
LOL, the point I am trying to make, is not that water vapor cannot "act as a feedback", obviously it does in response to solar input through oceans, geological, biomass and anthropogenic mechanisms.
CO2 is added to and subtracted from the atomsphere from oceans, geological, biomass and anthropogenic mechanisms acting as a feedback to solar input in the same manner, though at an attenuated degree in comparison to H20.
The Position of IPCC is that the dominant driver is CO2 and everything else is considered as a source of minimal change(i.e. solar flux) or is a feedback in relation to CO2 forcings. The nonsense of IPCC and the UN agenda is to place CO2 into a politically dominant role and does so by identifying water vapor as a "feedback" redefining it into a secondary role and placing other minority IR active gases as "GHG" to encourage regulation anthropogenic CO2 sources as a political goal.
That IPCC characterisation, which Hansen repeats, is one of many things that I and others take objection to, for that characterisation obscures reality to support a political agenda.