So is it?
Let’s start to crack this open. Since the judge hasn’t delivered his decision we’ll be careful, but I’m advised we can discuss it freely as long as we don’t insult the judge (or NIWA’s scientists, for that matter). [ADDENDUM: Or attempt to influence the judge's decision.]
There are several incongruous aspects of NIWA’s 7SS adjustments that have always mystified Coalition* members:
- The whole warming trend of about 1.0°C/century is brought about by pre-1945 downward adjustments, which are curiously linear (see graphs).
- Although the site changes causing them are random, over 90% of the adjustments move in the same direction; they do not balance out as the literature suggests they should.
- The 7SS adjusted warming trend is inconsistent with the official temperature series published in 1867 and 1920; these showed that the nationally-averaged temperatures recorded back then were just as high as they are now.
- The largest New Zealand warming occurred during the half-century 1909-59, with the second highest being 1859-1909. The period 1959-2009 – which coincides with IPCC-reported global warming – shows the smallest trend (only 0.4°C/century).