On 1 July 2025, NIWA merged with GNS Science to become Earth Sciences New Zealand.

30-day SST anomalies and marine heatwave conditions (stippled), calculated with respect to the 1991-2020 climatological period..png

NIWA

30-day SST anomalies and marine heatwave conditions (stippled), calculated with respect to the 1991-2020 climatological period.