On 1 July 2025, NIWA merged with GNS Science to become Earth Sciences New Zealand.
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Surface temperature anomalies (ºC) for March 2015, data is from the NOAA OISST Version 2 dataset, available at the NOAA’s Climate Data Center (ftp://ftp.cdc.noaa.gov/Datasets/noaa.oisst.v2.highres/).