NIWA's work on long-term temperature trends has been subject to various review processes.

The content of NIWA's website on long-term temperature trends is dynamic and continues to evolve, as we add more analysis and detail. For the purposes of transparency, we have posted a list of changes and links to old versions.

List of changes and links to old versions

Peer review

In February 2010, NIWA published a report describing how the long-term temperature series for Hokitika was calculated as part of the 'seven-station' temperature series.

NIWA then agreed to prepare and place on the web similar documents for the other six locations used in that series.

NIWA approached the Bureau of Meteorology in Australia to ask whether their climate scientists would undertake an independent external peer review of the methodology and documentation of the series, and they agreed. All documents have also been internally peer reviewed.

NIWA scientists have addressed the feedback from peer reviewers and have produced final versions of the reports for all the stations making up the seven stations series.

More information on the re-analysis of and documentation for these stations

NIWA welcomed this opportunity to have independent expert review of its work by suitably qualified climate scientists.

Judicial review

In July 2010, the New Zealand Climate Science Education Trust filed a Statement of Claim in the High Court which is seeking a judicial review of some of NIWA's actions relating to the analysis of long-term temperature trends in New Zealand, especially the 'seven-station' series. The reanalysis and peer review of the seven station series forms part of the judicial review action. NIWA sought the peer review, in part, to further verify that its scientific processes are sound. The court action recently concluded and found in our favour.

Read our media reliease 'Endorsement of NIWA's science welcome'