The recently released Copenhagen Diagnosis assessment has been accomplished by 26 scientist, down from 4000 or so that contributed to the Fourth IPCC Report. These 26 have been described to be 'leading scientists', raising the question ‘what are they leading us to’?.
The assessment is theoretically based on peer-reviewed literature, and thus was not intended to include new research. It aims to just up-date the findings of Working Group I (The physical basis) of the IPCC summarized in the Fourth IPCC Report. The Copenhagen Diagnosis may be indeed be based on peer-reviewed studies, but it soon becomes clear that it is not based on all peer-reviewed literature, and not even on the most relevant peer-reviewed literature. The selection of published papers that the authors had considered worthy of assessment is indeed quite worrying.
Let us consider the projections for sea-level rise for year 2100. The Copenhagen Diagnosis indicates that global sea-level could rise up to 'at least twice as large as that presented by IPCC AR4 with an upper limit of 2 m' . There are, indeed, published studies that estimate a sea-level rise of that magnitude. For example the one by Rahmstorf (Science 07), solidly founded on a statistically robust regression analysis based on 4 to 6 degrees of freedom. Rahmstorf's results are quite prominently displayed in the Diagnosis chapter devoted to global sea-level rise. It is, however, disturbing that results of just one team are prominently display in a figure in a climate assessment written by that very same team. We are now suffering the consequences of this hockey-stick-strategy implemented several years ago. As a rehearsal of a deja-vu, two recent papers about global sea-level projections published in Nature Geosciences are simply not discussed and not even cited. Why?
The first reason we must consider, of course, is that the excluded research is of poor quality. The inclusion of the work in Nature Geosciences presumably makes that reason highly unlikely (although I do note the rather high percentage of papers published in Nature and Science seem to later be disproven). It is also of note that the authors of the excluded papers have long publication records on global sea-level, and one is the coordinating author of the next IPCC report.
Having ruled out the quality of both papers and authors as being overly problematic there is no option but to turn to the actual contents of the two papers. Both abstracts state clearly that global sea-level rise in year 2100 will likely remain under 1m, and thus contradict Rahmstorf 07. Two critical comments to Rahmstorf 07, along with Rahmstorf's responses, were also published in Science in 2007. These critical comments have been ignored in the Copenhagen Assessment as well.
Polls indicate that public conviction about the existence of anthropogenic global warming is wobbling. I think that this strategy of 'hide-and-scare' was and is becoming the most serious threat for the IPCC and for a rationally agreed solution. It is the time for surgery that we are running out of.