Much back and forth on climate blogs about this paper, Influence of the Southern Oscillation on tropospheric temperature, by AGW deniers J. D. McLean, C. R. de Freitas (who I have written about previously here), and R. M. Carter. It has been touted by Morano as yet another refutation of AGW theory and, indeed, the paper's press release makes just such claims:
Nature not man responsible for recent global warming
Bob Carter, one of four scientists who has recently questioned the justification for the proposed Australian emissions trading scheme, says that this paper has significant consequences for public climate policy.
"The close relationship between ENSO and global temperature, as described in the paper, leaves little room for any warming driven by human carbon dioxide emissions. The available data indicate that future global temperatures will continue to change primarily in response to ENSO cycling, volcanic activity and solar changes.”
“Our paper confirms what many scientists already know: which is that no scientific justification exists for emissions regulation, and that, irrespective of the severity of the cuts proposed, ETS (emission trading scheme) will exert no measurable effect on future climate.”
However, faced by a barrage of withering criticism in the blogosphere, for example
That ENSO is a major contributor to variability in global temperature, is ancient news[....]That ENSO is a major contributor to recent trends in global temperature, they have not shown — not even “perhaps.” In fact it’s downright impossible for their methodology to do so.
...co-author De Freitas has essentially disowned the remarks from his own presser. This admission occurs deep in the comments at Watts Up With That:
Chris de Freitas (16:08:44) :
The paper by McLean et al (JGR, 2009) does not analyse trends in mean global temperature (MGT); rather, it examines the extent to which ENSO accounts for variation in MGT.
Since so much of the criticism in the blogosphere to date is about the failure of the McLean et al paper to detect trends, which was not the aim of the paper
What this means is that Mr. de Freitas is admitting that his paper says nothing of significance about the existence/non-existence of AGW, contra the statements in its press release. Kudos to Joel Shore (also in the WUWT comments) for screwing this admission out of Mr. De Frietas.
And if you are wondering how the paper made it through peer review in the first place, there is an interesting trick AGW skeptics will sometimes employ (Roy Spencer does this sometimes) wherein they make their wild and crazy assertions in the press release to the paper, but leave them out of the paper itself. That is, the paper becomes an occasion for a polemic conducted via press release, blogosphere, and MSM. That seems to be what has occurred here.
PS. The same climb-down, posted by McLean and attributed to all three co-authors, also appears in the comments at Real Climate.
PPS ESNO=El Niño