Patrick Michaels describes some of the long history of the Hadley Center and specifically Phil Jones’ resistance to third party verification of their global temperature data. First he simply refused to share the data
We have 25 years or so invested in the work. Why should I make the data available to you, when your aim is to try and find something wrong with it?
(that’s some scientist, huh) and then he said he couldn’t share the data and now he says he’s lost the data.
Michaels gives pretty good context to the issues of station siting, but there are many other issues that are perfectly valid reasons for third parties to review the Hadley Center’s methodology. A lot of choices have to be made in patching data holes and in giving weights to different stations and attempting to correct for station biases. Transparency is needed for all of these methodologies and decisions. What Jones is worried about is whenever the broader community (and particularly McIntyre and his community on his web site) have a go at such methodologies, they have always found gaping holes and biases. Since the Hadley data is the bedrock on which rests almost everything done by the IPCC, the costs of it being found wrong are very high.