Please enable JavaScript to view the comments powered by Disqus. blog comments powered by Disqus

Official Reanalysis demonstrates consistent Cooling of New Zealand since 1909

Official Reanalysis Demonstrates Consistent Cooling of New Zealand Since 1909

Nostalgic readers might fondly remember last November’s NIWAgate, little New Zealand’s very own miniature Climategate, in which our good Friends the New Zealand Climate Science Coalition, eager to get in on the action, accused the agency responsible for the country’s climate analysis of fudging the numbers. NZCSC ‘uncovered’ adjustments to the freely-available temperature data used to make up the country’s semi-official climate record and were outraged to discover that these adjustments made a warming trend out of what appeared to be no trend at all. That they chose to ignore station moves and equipment changes -- corresponding with the times of these adjustments and clearly documented in the accompanying metadata -- as “unremarkable” could perhaps have been seen as a flaw in their analysis, but it was nonetheless pounced upon by devious heroic politicians as evidence of a conspiracy in support of the contentious national emissions trading scheme.

In response to the brouhaha and in addition to releasing a compilation from 11 temperature stations where adjustments had not been necessary, NIWA quietly embarked upon a reanalysis of their original ‘seven-station’ adjusted series. Their review of this reanalysis has recently been released, and predictably it shows no significant change from the original. Predictably, too, it hasn’t satisfied the brilliant and creative scientists at the NZCSC, who, while continuing to provide interpretations that would not occur to less imaginative minds, have not yet presented their full statistical analysis and critique of the new record. While not wanting to scoop our kiwi colleagues, we feel that such important work deserves to be out in the public arena as quickly as possible. Hence, FoGT’s statistics department has prepared the graph below.


The data series, directly from NIWA (spreadsheet link on this page), incorporates their new adjustments and can therefore be expected to be as ‘warm’ as they reckon they can get away with. Using techniques from Canada’s Friends of Science and leading blog climatologist the Baron von Monckhofen, we fit to this seven-station compilation seven trends which together cover the entire period 1909-2009. Despite the data adjustments each of these trends is negative, demonstrating convincingly that New Zealand has been consistently cooling throughout the 1909-2009 period. Furthermore, careful inspection of the graph reveals another important fact: the gradients of the three regression lines on the right of the figure show that cooling has accelerated since 1970. These two key observations from the New Zealand data agree with what scientists who are not members of the conspiracy have long been saying about trends globally.

We’re pleased to be able to present these important results in a timely fashion. We trust they’ll add to the reputation we have established as climate statisticians with, for example, our findings that marmots can predict climate and our invention of the weather model. We remain, as ever, available to assist our friends in organizations like the Friends of Science and the NZCSC in such areas where their own statistical expertise may be lacking.