The Dog Ate my Data

"In December, NZCSC issued a formal request for the schedule of adjustments under the Official Information Act 1982, specifically seeking copies of “the original worksheets and/or computer records used for the calculations”. On 29 January, NIWA responded that they no longer held any internal records, and merely referred to the scientific literature."

“The only inference that can be drawn from this is that NIWA has casually altered its temperature series from time to time, without ever taking the trouble to maintain a continuous record. The result is that the official temperature record has been adjusted on unknown dates for unknown reasons, so that its probative value is little above that of guesswork. In such a case, the only appropriate action would be reversion to the raw data record, perhaps accompanied by a statement of any known issues,” said Terry Dunleavy, secretary of NZCSC.

“NIWA’s website carries the raw data collected from representative temperature stations, which disclose no measurable change in average temperature over a period of 150 years. But elsewhere on the same website, NIWA displays a graph of the same 150-year period showing a sharp warming trend. The difference between these two official records is a series of undisclosed NIWA-created ‘adjustments’.

...

“Well qualified climate scientist members of our coalition believe that NIWA has forfeited confidence in the credibility of its temperature recording procedures, and that it cannot be trusted to try to cover up its own ineptitude by in-house adjustments. What is needed is open access in the public domain to all of the known reasons for post-reading adjustments to enable independent climate analysts to make their own comparative assessments of temperature variations throughout New Zealand since the middle of the 19th century,” said Mr Dunleavy.