2011-04-07 04:00:17Watts and Whitehouse on Stratospheric Water Vapor - are Whitehouse's "estimates" defensible?
Alex C

coultera@umich...
67.149.101.148

Posted today, "Stratospheric water vapor may have contributed about a third of the warming 1980-2000 but now is in decline"

Disregarding the fact that he misstated the temperature increase between 1980-2000 as 0.5˚C (it's more like <0.4˚C with a 5-year moving average, as I've been keeping track of myself), I found Whitehouse's docking of recent temperature increase to be very sketchy and without much support.  Can I have some second opinions?  His claims of 0.1˚C/dec for solar forcing and a long term forcing from the NAO and PDO of 0.1˚C each ("conservatively") strike me especially as not being what I have grown to understand from the literature.  And he cites "the literature."

2011-04-07 04:07:09
Alex C

coultera@umich...
67.149.101.148

It seems like he is arguing for a low climate sensitivity by implying that there will be a long term decrease in SWV which will have a cooling effect.  This feedback idea however doesn't, I think, jive with the idea that it was responsible FOR a major portion of the warming during the 1980-2000 period, as one would expect decreasing SWV in such a scenario, not increasing SWV as happened.

2011-04-07 04:17:13
Daniel Bailey
Daniel Bailey
yooper49855@hotmail...
97.83.150.37

Tamino has debunked Whitehouse several times.

If Whitehouse says the sky is blue, I'd double-check it to be safe.

Whitehouse=paid disinformationist.

2011-04-07 05:25:08horrid
dana1981
Dana Nuccitelli
dana1981@yahoo...
64.129.227.4

Pretty horrid post by Whitehouse, although par for the WUWT course.

First problem, Whitehouse ignores the fact that the same paper says that stratospheric water vapor has had a 25% cooling effect in the '00s, which basically offsets the 30% warming effect in the '90s.  That's a pretty egregious error.  I mean shit, it's right there in the abstract that he linksThe '00s cooling is even mentioned before the '90s warming!  Moving on, emphasis added:

"The sun has a a decadal influence of about 0.1 deg C (some solar physicists say slightly larger)...0.1 deg C seems to be a good ballpark figure that is often quoted as the major climate driver before 1950.  Clearly, whenever AGW became dominant (1960- 80 according to the IPCC), the sun’s influence did not suddenly go away, especially at a time of historically high solar activity....So perhaps we can conservatively account for another 0.1 deg C per decade since 1980 which, in our hypothetical game of accounting for the recent changes on Earths temperature might account for up to 0.2 deg C, leaving about 0.2 deg C unattributed since 1980."

Gah, so bad!  I think it's reasonable to say that solar activity can have a 0.1°C influence on temps on decadal scales, but notice that Whitehouse has given us no reason whatsoever to believe that solar activity did cause a 0.1°C warming since 1980.  All he did was wave his hands around and then call it 0.1°C for no apparent reason.  If anything, TSI has a negative trend over that period.

"The North Atlantic Oscillation went strongly positive around 1980, and so did a few years later the Pacific Decadal Oscillation. The scientific literature contains a range of estimates of the influences of these factors but, again being conservative, 0.1 deg C for both of them doesn’t seem too outrageous."

Again, no reason whatsoever to actually believe that either NAO or PDO had a 0.1°C warming effect since '80.  He just posits that it's a hypothetical possibility.  He concludes that his wholly unsubstantiated hypotheses "make him wonder".

"Have we just lived through a period where a handful of natural decadal and longer variations have conspired to act in the same direction pushing temperatures up? When I read a peer-reviewed paper in a major journal (Solomon’s paper was published in Science) that plucks from the air an explanation for a third of the warming seen since 1980 via a previously little regarded mechanism [which of course, it didn't], I begin to wonder."

So, so stupid.  I'm almost tempted to do a blog post response to this.  Maybe do a rebuttal to "it's stratospheric water vapor".

PS - tamino calls Whitehouse "inaccurate, unfair, and dishonest"

2011-04-07 06:06:55
Alex C

coultera@umich...
67.149.101.148

I think more to his point, the *decrease* in stratospheric water vapor during the past decade had a cooling effect (well, that was Soloman's point).  Again though, the trend in prior decades does not fit the idea of a negative feedback, and if SWV was a forcing driving temperature changes, then what triggered the changes in SWV in the first place?  Magic?  Whitehouse gives no mechanism.  It seems like there needs to be more research into this topic.  If, say, the trigger/driver of decadal variance in SWV is solar-based, then that is quite independent of any climate sensitivity response due to CO2 and would instead affect the efficacy of sensitivity due to solar output.

I too though wonder why he didn't just form an analogy of throwing darts.  He was right on track to do so.

2011-04-07 06:17:36
Alex C

coultera@umich...
67.149.101.148

Or were you talking about his attempt to modify temperatures?  Sorry, misinterpreted what you meant.

Gotta give him credit for knowing which facts support which idea of his, at least.  Perhaps he'll choose one eventually?

2011-04-07 07:54:55temps
dana1981
Dana Nuccitelli
dana1981@yahoo...
64.129.227.4

I was talking about Whitehouse's attempt to attribute warming since 1980 to any non-anthropogenic effect he could come up with.  Like for example, ignoring the decrease in stratospheric water vapor over the past decade.