Hadcrut temperatures are fraudulent, for the Climategate files reveals that no one knows how they were constructed.
The Air vent attempts an honest reconstruction:
Of course, this reconstruction can only be as good as the data it rests on, which we now know from the Climategate documents directory to be poor. I argue we should throw out all dubious data – which likely means we should rely on proxy indications of temperature for the early part of the century.
The fact manufacturing found in the Climategate documents, especially the HarryReadMe files, gives a whole new meaning to the phrase “man-made global warming”.