I was surprised to see reports this morning on Seemorerocks that New Zealand had experienced its warmest winter since records began, according to the National Institute of Water and Atmospheric Research (NIWA).
NIWA offers a figure of 1.14°C above average for the winter just ended.
The Institute’s chart indicates record taking began in 1909 at seven stations. Wellington is one of the seven but I don’t know how close it is geographically to Wellington International Airport (“my station”).
Last year, my Wellington failed to report almost four weeks of winter data to Weather Underground, so I had to use proxies for the missing days. My “normal” is calculated for ten years (2008-2017); the Institute’s from 1981 to 2010.
Wellington isn’t quite half the way down the two main islands but can be considered roughly average for temperature at the seven stations.
My 10 Year winter average: 10.1°, 2019: 11.5°, 2020: 11.0°C.
Putting my Wellington’s winters in their yearly context gives the following chart.
The weekly means are running averages from the beginning of the meteorological year. They confirm that Wellington has been much cooler this year than last. I’m not disputing NIWA’s figures. The other six NIWA stations have perhaps more than compensated to make this year’s NZ winter the warmest since 1909.
Even though Wellington International is much cooler this year than last, its IPCC Unit score shows it is well ahead of schedule to “reach Paris” by 2040. Adding 12 units of 0.0217°C (the per annum rise) to the IPCC’s projected 1.065°C at the end of this meteorological year gives the 1.33 degrees above Pre-Industrial in Week 39 shown above.
Read more about the Seven Station Temperature Series here.