This Climategate email from Michael Mann that is relevant:
Recently rejected two papers (one for JGR and for GRL) from people saying CRU has it wrong over Siberia. Went to town in both reviews, hopefully successfully. If either appears I will be very surprised, but you never know with GRL.
Demonstrating another classic case of climate bullying by "the team."
So what was it that Dr. Mann was so keen to protect?
In this article by Jeff ID of the Air Vent Blog, entitled: Russia Accuses CRU of Tampering he states:
It’s true, and it’s huge. Today another example of CRU having their foot on the scale, Russian papers are reporting that the Russian surface station data was sorted by CRU to use the highest warming stations only.
Russia affected by Climategate
A discussion of the November 2009 Climatic Research Unit e-mail hacking incident, referred to by some sources as “Climategate,” continues against the backdrop of the abortive UN Climate Conference in Copenhagen (COP15) discussing alternative agreements to replace the 1997 Kyoto Protocol that aimed to combat global warming.
The incident involved an e-mail server used by the Climatic Research Unit (CRU) at the University of East Anglia (UEA) in Norwich, East England. Unknown persons stole and anonymously disseminated thousands of e-mails and other documents dealing with the global-warming issue made over the course of 13 years.
Controversy arose after various allegations were made including that climate scientists colluded to withhold scientific evidence and manipulated data to make the case for global warming appear stronger than it is.
Climategate has already affected Russia. On Tuesday, the Moscow-based Institute of Economic Analysis (IEA) issued a report claiming that the Hadley Center for Climate Change based at the headquarters of the British Meteorological Office in Exeter (Devon, England) had probably tampered with Russian-climate data.
The IEA believes that Russian meteorological-station data did not substantiate the anthropogenic global-warming theory.
Analysts say Russian meteorological stations cover most of the country’s territory, and that the Hadley Center had used data submitted by only 25% of such stations in its reports.
Over 40% of Russian territory was not included in global-temperature calculations for some other reasons, rather than the lack of meteorological stations and observations.
The data of stations located in areas not listed in the Hadley Climate Research Unit Temperature UK (HadCRUT) survey often does not show any substantial warming in the late 20th century and the early 21st century.
The HadCRUT database includes specific stations providing incomplete data and highlighting the global-warming process, rather than stations facilitating uninterrupted observations.
On the whole, climatologists use the incomplete findings of meteorological stations far more often than those providing complete observations.
IEA analysts say climatologists use the data of stations located in large populated centers that are influenced by the urban-warming effect more frequently than the correct data of remote stations.
The scale of global warming was exaggerated due to temperature distortions for Russia accounting for 12.5% of the world’s land mass. The IEA said it was necessary to recalculate all global-temperature data in order to assess the scale of such exaggeration.
Global-temperature data will have to be modified if similar climate-date procedures have been used from other national data because the calculations used by COP15 analysts, including financial calculations, are based on HadCRUT research.
They specifically state that lack of measurement is not the cause. If they claim the full set of Russian data does NOT support global warming, imagine how different the bright red dot over Russia would look. Again the accusation is completely believable, yet is completely unverifiable because CRU has refused to release the data. This data and code release is the subject of illegal blocking of FOIA’s is one of the keys in the Climategate emails. We need to know the list of stations used and we must have copies of the raw data.
This is a very powerful accusation, which if true could change much about the climate science debate. Many papers are based on this dataset which has the highest trend of the major ground datasets.