After I wrote and scheduled this post, I see that John Christy and Roy Spencer have a directly related weblog post titled
which appeared yesterday.
As many of you may know, Gavin Schmidt was critical of our paper
Klotzbach, P.J., R.A. Pielke Sr., R.A. Pielke Jr., J.R. Christy, and R.T. McNider, 2009: An alternative explanation for differential temperature trends at the surface and in the lower troposphere. J. Geophys. Res., 114, D21102, doi:10.1029/2009JD011841
where we concluded that
“This paper investigates surface and satellite temperature trends over the period from 1979 to 2008. Surface temperature data sets from the National Climate Data Center and the Hadley Center show larger trends over the 30-year period than the lower-tropospheric data from the University of Alabama in Huntsville and Remote Sensing Systems data sets. The differences between trends observed in the surface and lower-tropospheric satellite data sets are statistically significant in most comparisons, with much greater differences over land areas than over ocean areas. These findings strongly suggest that there remain important inconsistencies between surface and satellite records.”
We looked at the issues he raised and clarified our analysis further in
Klotzbach, P.J., R.A. Pielke Sr., R.A. Pielke Jr., J.R. Christy, and R.T. McNider, 2010: Correction to: “An alternative explanation for differential temperature trends at the surface and in the lower troposphere. J. Geophys. Res., 114, D21102, doi:10.1029/2009JD011841″, J. Geophys. Res., 115, D1, doi:10.1029/2009JD013655
where we concluded that the findings in our 2009 paper are robust. In our 2010 paper, we concluded that, with respect to our 2009 paper,
“….no changes are needed in our paper’s conclusions.”
There is now an independent confirmation of our results as reported by Steve McIntyre in his weblog post
on November 7 2011. I expected a further response from Gavin Schmidt on this issue, but have finally decided to post on Steve’s post and comments as there has been no additional interaction’s on this subject that I am aware of.
In Steve’s post, he concluded that
“….the discrepancy between the revised downscaling of Klotzbach et al 2010 and Schmidt’s Nov 2009 realclimate post – is now totally reconciled. The amended numbers of Klotzbach et al 2010 appear reasonable.
Gavin Schmidt’s criticism of the downscaling over land in Klotzbach et al 2009 and of my original graphic in Closing BEST Comments post was justified, but his own figures for downscaling were incorrect. The diagnosis of the discrepancy was complicated by the fact that his actual method did not correspond to the most reasonable interpretation of his realclimate article. Thanks to Gavin’s clarifications, we now have what seems to be a definitive diagnosis of the discrepancy and where Gavin got wrongfooted. It seems to me that it would be constructive to note the resolution of the discrepancy in the original RC post.”
The significance of the discussion between Steve and Gavin is that the large discrepancy between the global annual average lower tropospheric and surface temperature anomalies remains. The Muller BEST analysis does not in any way alter this conclusion.
The current discrepancy can be see in the three figures below. The BEST analysis is only for the land, but the ocean anomalies would have to be significantly negative to result in an anomaly plot close to the RSS analysis of lower tropospheric temperatures. The GISS analysis presented in the third figure shows that the positive temperature anomalies, which are much higher than the RSS (and, the UAH) lower tropospheric anomalies, persist in the global average.
Fig 1. Lower tropospheric global average temperature anomaly from RSS with the bottom axis 1979 to 2012 in yearly tick marks [from http://www.ssmi.com/msu/msu_data_description.html]
Fig 2. BEST global-land average surface temperature anomalies [from http://berkeleyearth.org/faq/]
Fig 3. Global surface temperature anomalies from NASA GISS [ http://data.giss.nasa.gov/gistemp/graphs/]