I have two graphics here comparing the “old” CRUTem2 data of Jones, with the new Hadley Centre CRUT3. Looking at 140 years of New Zealand land based data and we now see huge extra warming in the Hadley Centre CRUT3 gridded data.
Both graphics tell a very similar story, the first uses data from a square of gridcells, 35-45 South, 170-180 East, which excludes Dunedin. Trends as follows.
The second uses data from three gridcells, 35-50 South, 170-175 East, which includes all main NZ cities but not the eastern North Island. Trends as follows.
I expect the Hadley Centre will do a similar adjustment to their Australian data.Data are from the KNMI ClimateExplorer climexp.knmi.nl/ (under “Select a Field, Take “Monthly Observations”)
See my post from January www.warwickhughes.com/blog/?p=82. There are now huge variations now between the 3 main global T datasets, where I said Jones was trending out of the picture in favour of the Hadley Centre.
Added 1 June: New web page setting out a perspective of compilations of the NZ land based T history from the 1986 work of Jones et al up to the Hadley Centre’s CRUT3.