Sorry, my link for the liberal meltdown should have been:
It seems that it isn't the New Zealand data alone that is questioned but we now have indications that the Oz temp data has not been quite upright either.
Again, it is WUWT that has the story.
I note that there are a lot of aerodromes seemingly included as weather stations.
In the US the responsibility for many weather stations, to ensure 24/7 manning, were posted on water treatment plans where temperatures are elevated anyway.
It seems from some of the comments that NZ and OZ stations may suffer similar problems.
The NZ defense of their temperature graph is shaky.
The NZCSC may have made a couple of mistakes, but the justification given for the example station in this blog post is a beautiful example of the art of junk science (once you get passed the overly long condemnation of the NZCSC's effort).
A thermometer was moved in the 1920s to a point higher above sea level. The CSC may have neglected to mention this. However, instead of using the small discontinuity at this point in the graph as the adjustment, Jim Salinger instead used the difference between this station's readings and one at the lower altitude Wellington Airport (to anyone unfamiliar with the issue, airports are notorious heat islands), whose record began in the 1960s, as his adjustment.
The difference, where before it was only slightly smaller during the move of the weather station, is now enormous. They then translate the graph of readings from the 1920s and earlier downward by this large difference. Lo and behold, you get a pronounced trend in temperature readings upward over the last century.