News souces indicate that all "other" sources are basing they data on the work done by Manchester.
As for the thermometer issue I must disagree somewhat. All of thos individual data sets produce an average on their own. Hence no need to tweek. Similar issue is Ozone days. Why are all the sensors placed in places known to have naturally higher levels of ozone. The result is higher reports of ozone over the entire area.
If it really were for "clarification" why then hide the "fudge factor"?

Quote Originally Posted by Thorne View Post
If Manchester has behaved in this manner then they won't maintain their preeminence for long. This is the very antithesis of good science. However, that does not negate the good science being done elsewhere.


Any properly designed experiment relies on properly calibrated instruments for the detection of data. These instruments should be calibrated on a specific schedule. If, for some reason, a stations instruments are not properly calibrated then their data is suspect and should be discarded. This does not say that the data is necessarily wrong, just that you cannot be sure it is right.
Tweaking of results is done to correlate data from differing environments. For example, if you are measuring the air temperature near your home and you use one thermometer which is in shade all of the time, another thermometer which is in sunlight most of the time, a third thermometer which is near the black top of the street and a fourth which is closer to a pond, you will get greatly differing results, solely due to local variations in the environment. You need to eliminate those variations to gain any meaningful results, which is done through tweaking. Contrary to what it may sound like, this is not done to force results, but to clarify them.