I'm looking at Research Paper No. 10-08 by Jason Johnston of the Institute for Law and Economics at the University of Pennsylvania (not to be confused with Pennsylvania State University where Michael Mann has his office). The idea of the report is to mimic a courtroom cross-examination of expert witnesses by non-scientist lawyers on the tenets of anthropogenic global warming. At first, we hoped that the report was a transcript of actual cross-examinations, but instead the cross-examination is performed by extracting quotations from peer-reviewed papers from climatology journals, and using these as answers to the questions posed by the author.
Here's one conclusion the author comes to. "Many of the ongoing disputes in climate science boil down to disputes over the relative validity and reliability of different observational datasets, suggesting that the very new field of climate science does not yet have standardized observational datasets that would allow for definitive testing of theories and models against observations."
In the section called "Questions about the Measurement of Land Surface Temperature Trends" the author discusses the global surface temperature provided by CRU, which we have examined in detail ourselves. But we never picked up on this point, which is the first one the lawyer-author makes.
"A daily average is computed as the midpoint between the nighttime minimum and daytime maximum temperature. From the mid 1950’s to the mid 1990’s, nighttime minimum daily surface temperatures in this dataset have risen about twice as fast as
daytime maximum daily surface temperatures.26 What is important to see is that most of the increase in global daily average surface temperature that is reported by the IPCC is due to an increase in nighttime minimum temperatures27 -- that is, daytime maximums have not increased by much over the period reported on by the IPCC."
The author assembles an explanation for why the nighttime minimums have risen, using quotations from existing papers. Every other sentence has a reference to a paper. According to the peer-reviewed literature, pavement replacing trees is one thing that raises nighttime minimums.
"There seems to be more and more evidence that there has indeed been a systematic trend upward since 1950 in the kind of variables that would have caused nighttime minimum temperatures to overstate actual surface warming."
This report will be a valuable resource to any lawyer challenging, for example, the EPA's ruling that CO2 is a pollutant. We ourselves have great faith in the courts as places where pseudo-science can be debunked. So we look forward to seeing lawyers taking on the climatologists.