From his web page: Why I think that Michael Mann, Phil Jones and Stefan Rahmstorf should be barred from the IPCC process
Short answer: because the scientific assessments in which they may take part are not credible anymore.
A longer answer: My voice is not very important. I belong to the climate-research infantry, publishing a few papers per year, reviewing a few manuscript per year and participating in a few research projects. I do not form part of important committees, nor I pursue a public awareness of my activities. My very minor task in the public arena was to participate as a contributing author in the Fourth Assessment Report of the IPCC.
By writing these lines I will just probably achieve that a few of my future studies will, again, not see the light of publication. My area of research happens to be the climate of the past millennia, where I think I am appreciated by other climate-research ‘soldiers’. And it happens that some of my mail exchange with Keith Briffa and Timothy Osborn can be found in the CRU-files made public recently on the internet.
To the question of legality or ethicalness of reading those files I will write a couple of words later.
I may confirm what has been written in other places: research in some areas of climate science has been and is full of machination, conspiracies, and collusion, as any reader can interpret from the CRU-files. They depict a realistic, I would say even harmless, picture of what the real research in the area of the climate of the past millennium has been in the last years. The scientific debate has been in many instances hijacked to advance other agendas.
These words do not mean that I think anthropogenic climate change is a hoax. On the contrary, it is a question which we have to be very well aware of. But I am also aware that in this thick atmosphere -and I am not speaking of greenhouse gases now- editors, reviewers and authors of alternative studies, analysis, interpretations,even based on the same data we have at our disposal, have been bullied and subtly blackmailed. In this atmosphere, Ph D students are often tempted to tweak their data so as to fit the ‘politically correct picture’. Some, or many issues, about climate change are still not well known. Policy makers should be aware of the attempts to hide these uncertainties under a unified picture. I had the ‘pleasure’ to experience all this in my area of research.
I thank explicitely Keith Briffa and Tim Osborn for their work in the formulation of one Chapter of the IPCC report. As it destills from these emails, they withstood the evident pressure of other IPCC authors, not experts in this area of research, to convey a distorted picture of our knowledge of the hockey-stick graph.
Is legal or ethical to read the CRU files? I am not a lawyer. It seems that if the files had been hacked this would constitute an illegal act. If they have been leaked it could be a whistle blower action protected by law. I think it is not unethical to read them. Once published, I feel myself entitled to read how some researchers tried to influence reviewers to scupper the publication of our work on the ‘hockey stick graph’ or to read how some IPCC authors tried to exclude this work from the IPCC Report on very dubious reasons. Also, these mails do not contain any personal information at all. They are an account of many dull daily activities of typical climatologists, together with a realistic account of very troubling professional behavior.