The pseudoscience wing has been in full tilt these days, probably trying to steal publicity from the unequivocal new sea ice minimum coming in the next couple of days (stay tuned) and the Mann defamation lawsuit that finally is going forward (he’s got a strong case this time), and the plethora of DKos articles.
I am probably the guy on the hook to refute the latest garbage from the tedious Pat Frank, which is right on my turf and as always with his climate related stuff, deeply misleading. But Frank seems to have endless time and will fillibuster. And there was another Wall Street Journal fiasco, too. This will take work. But I’ve caught a habitual denier in a flat out misrepresentation and I thought it best to report it quickly lest yet another dishonest meme propagate beyond Morano, who of course is already running with it.
In an article you just know from the title is going to be wrong called “Global Warming Theory Fails Again” by Jonathan Duhamel, we see
A new paper, Trends in U.S. surface humidity, 1930 – 2010, Journal of Applied Meteorology and Climatology, finds just the opposite: “Average long-term trends (1930 – 2010) indicate that temperature has warmed, but little change has occurred in dewpoint and specific humidity.”
But reading the abstract we see:
Average long-term trends (1930 – 2010) indicate that temperature has warmed, but little change has occurred in dewpoint and specific humidity. … There is evidence of inhomogeneity in the relative humidity record that primarily affects data prior to 1950. … Trends since 1947 indicate that the warming of temperatures has coincided with increases in dewpoints and a moistening of specific humidity. … Nationally, trends in relative humidity show little change for the period 1947 – 2010 during which these data are more homogeneous.
Now, leaving aside all sorts of questions about how land should respond to heating and how noisy American data is as an estimate of the world, consider the claim that “little change has occurred in dewpoint and specific humidity“. Leave aside that dewpoint and specific humidity are the same thing measured with different units. Just note that the abstract says “little change in relative humidity”, “moistening of specific humidity”. These differ with temperature.
Which matters for radiative feedback? Why, it’s the specific humidity. The one that’s actually going up. The one Duhamel says is not changing.
There are all sorts of additional caveats here, as you’ll see if you look up the abstract. More to the point this is a very noisy test of the hypothesis – it can’t prove anything either way. American deniers often take advantage of American backwoods parochialism and confuse American and global records. (After all the national and world records are the same in baseball and football, right?)
But the abstract is specific about “specific humidity” – it moistened and about “relative humidity” – no clear trend. If you look through the literature you will see that this is very mainstream and unsurprising. As a back of the envelope calculation it is usual to treat relative humidity as constant, which means more water in the atmosphere column. This is supported heuristically and in models. So if this paper is evidence of anything, it supports mainstream science. The only “Fail” is Mr. Duhamel’s
Did Mr. Duhamel make this convenient mistake accidentally?
The bottom line is that the sea ice may vanish and the land ice may crumble before we will be rid of people who select evidence to fit their opinions rather than modifying their opinions to fit the evidence.