2021 officially New Zealand's hottest year on record, Niwa says
2021 was the warmest year on record, Niwa has confirmed.
The country saw an average temperature of 13.56 degrees Celsius, almost an entire degree above the 1981-2010 average. It’s the warmest since records began back in 1908, with the previous hottest year being 2016.
Niwa released its annual report of weather and climate activity across the country on Tuesday. The report shows all six main centres recorded above-average temperatures.
Auckland was the warmest of the main centres, recording an average temperature of 16.5 degrees across the 12 months.
Dunedin was the coolest and driest, Wellington was the wettest and Tauranga was the sunniest. Hamilton saw the least sun of the six centres, but still recorded an above-average temperature of 14.7 degrees.
The highest temperature of 2021 was recorded in Ashburton almost a year ago on January 26, a scorching 39.4 degrees – the second-highest January temperature on record and tenth-equal highest of all time.
Niwa forecaster Nava Fedaeff said it’s likely the warm weather will continue into 2022.
“Niwa does project an outlook for the next couple of months, the warmth is set to continue,” said Fedaeff.
“We’ve had a warm start to January – we haven’t had any extreme temperatures so far, but consistently warm temps in the 30s, which is to be expected. I’d expect it to continue for the next three months.”
The nationwide temperature was measured by Niwa’s seven-station temperature series, which began in 1909.
Seven of the past nine years have been among New Zealand’s warmest on record, and Niwa says this trend is consistent with the overall pattern of global warming.
Daily data based on Niwa’s Virtual Climate Station Network shows for the country as a whole, 55 per cent of the year featured above or well-above temperatures.
Frequent high pressure over the North Island and east of the country, which resulted in more northerly quarter winds than normal, was a contributor to New Zealand’s warmest year on record.
The highest ever recorded temperature in New Zealand was 42.4 degrees in Rangiora, Christchurch, on February 7, 1973.
Fedaeff said records for the hottest temperatures were often set on the east coast of the South Island due to the southern alps.
“It’s often when a northwesterly wind flow comes down the alps and through the other side. Generally we need that westerly to come from Australia,” she said.
The summer of 2021 brought the hottest spell of the year, between January 25 and 28. Several locations reached their record or near-record high daily maximum temperatures.
As the year transitioned into autumn, long dry spells were observed across the country with bursts of heavy rainfall. Winter, however was New Zealand’s warmest on record – surpassing the previous record set during the winter of 2020.
Redeveloping oceanic conditions lead to a spring with near-average temperatures, before increasing to bring the country’s fifth-warmest October, the warmest November and fourth-warmest December on record.