Last year was New Zealand's warmest-ever on record, NIWA announced today, the second year in a row the record's been broken.
The top four warmest years on record have all occurred since 2016.
2022 surpassed the record set in 2021 by a "significant" 0.2C, and not a single month of last year was below average, NIWA said, with 10 above average and just two registering at average temperatures.
And it was also the eighth most unusually wet year on record, the agency announced at its Annual Climate Summary.
"Of the six main centres in 2022, Tauranga was the wettest, Dunedin was the driest and coolest, Auckland was the warmest, Hamilton was the sunniest, and Wellington was the least sunny," a statement announcing the results said.
"La Niña was one of the primary drivers of last year's weather patterns.
"Sea surface temperatures near New Zealand also had a big impact, being above or well above average every month and resulting in a marine heatwave for most of the year."
New temperature record set by 'a significant margin'
NIWA Principal Scientist Chris Brandolino said Aotearoa's annual national mean temperature last year was 13.76C.
"This is 1.15C above the long-term average," he said. "And it surpasses last year's value by a significant margin, by 0.2C."
It comes after data released overnight by Copernicus, the EU's climate monitoring service, showed 2022 was the fifth warmest year on-record globally - with the last eight years now the warmest eight yet recorded.
Roughly 83% of the planet experienced above-average temperatures last year, Brandolino said.
In New Zealand, the year included the third-warmest May on record, the fourth-warmest July on record, the second-warmest August on record, and the warmest November on record.
It was also the warmest winter on record and the joint-second warmest autumn on record.
"This happened in spite of not one but two significant cold snaps," Brandolino said, one in September and one in October.
For rain, August was 'a doozy'
Last year, New Zealand began with a very dry start in January - but ended up having its most unusually wet year since 2018, with a nationwide rainfall anomaly (the percentage of rain relative to the 1981-2010 baseline) of 110%.
It was also the wettest winter New Zealand's seen on record.
The atmospheric river that brought flooding to the top of the South Island in August was a big factor.
"Boy, did we have a doozy in August," Brandolino said. "An analysis by NIWA indicated that this was the strongest August atmospheric river in the New Zealand region since records began back in 1950.
"These numbers are incredible...this landfalling [atmospheric river] resulted in a one-in-120 year rain event in Nelson."
February was also unusually wet, with ex-tropical Cyclone Dovi impacting our shores.
The role of climate change
Brandolino stressed that he is a forecasting expert, not a climate change expert - but "of course, we have to consider and acknowledge climate change," he said. "Climate change continues to influence New Zealand's long-term temperature track.
"Climate change makes extreme weather events more likely, it makes them more frequent, and it makes them more intense."
Looking ahead to 2023, Brandolino said "it's hard to see us breaking from the trend that we're on" in terms of extreme weather.
It comes as Cyclone Hale has battered much of the North Island's east coast this week.
SHARE ME