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

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'

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    This is a record of changes made to the section of NIWA's website relating to our analysis of New Zealand temperature trends.
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    Technical notes on seven-station temperature series data

    Technical changes relating to data in the seven-station temperature series
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    'Seven-station' series temperature data (archive)

    NZ ‘seven-station’ temperature series data for download
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    Technical note on Hokitika station agent numbers

    Hokitika temperature data used in the NIWA seven-station temperature series have now been split into two stations
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    Technical note on addition of data for Kelburn, December 1927

    Temperature data for December 1927 at Kelburn have been added to the NIWA Climate Database
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    Technical note on addition of early Nelson climate records

    Temperature measurements for the Nile St Vicarage in Nelson have now been digitised.
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    Technical note on correction of value for Waingawa, April 1910

    An incorrect value of monthly mean temperature for Waingawa for April 1910
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    Technical note on in-filling of missing data for ‘Masterton’ in 2016

    In April and May 2016, the Martinborough EWS (agent 21938)1 experienced some technical difficulties, and a number of 9 am observations were missing
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    Technical note on revised January 1945 Hokitika Adjustment

    Two alternatives offered for the adjustment at January 1945 between the records for Hokitika Town and Hokitika Southside