New Zealand has had its warmest winter since records began more than 100 years ago, according to official climate data.

The National Institute of Water and Atmospheric Research’s (Niwa) Seven Station Temperature Series, which began in 1909, shows the 2020 winter was 1.14C above average.

Niwa forecaster Ben Noll said that seven of the 10 warmest winters on record in New Zealand have now occurred since 2000. “It just showcases the trajectory that we are on,” he said.

Noll said that, decades into the future, these present-day records might be more like average winters for the country and that would have impacts across many sectors of society.

Seventeen locations around the country had record breaking-mean winter temperatures, and 53 other locations ranked within their top four warmest winters.

The highest recorded winter 2020 temperature was 25.1C on 30 August in Timaru. It was the highest temperature recorded there during winter since records began in 1885. It was also the equal-fourth warmest winter temperature on record for the whole of New Zealand.

The lowest temperature was -12.3°C, observed at Middlemarch, in the South Island’s Otago region, on 14 June.

“It might feel nice to have a warm winter,” Noll said. “But you have to appreciate the full reasons behind it.”

He said the winter warmth can be attributed to several “natural” factors including more warmer, sub-tropical winds, and higher air pressure than usual.

“This contributed to a sunnier-than-normal winter in much of the South Island and lower North Island.”

There were also above average sea-surface temperatures and, as an island nation, New Zealand’s air temperatures are strongly influenced by the waters surrounding it.

In November, New Zealand passed landmark climate change legislation, with historic cross-party support, committing the nation to reduce its carbon emissions to zero by 2050 and to meeting its commitments under the Paris climate accords.

At the time, the climate change minister, James Shaw, said the bill, which committed New Zealand to keeping global warming below 1.5C, provided a framework for the country to adapt too, and prepare for the climate emergency.

Noll said the above average temperatures recorded was consistent with the country’s long-term climate-change trend, caused by greenhouse gas emissions.

“You have to look under the hood, and you have climate change and are living in a warming world.”

Noll said the higher temperatures contributed to a difficult ski seasonas the tourism industry struggled to get enough snow to lure customers.

Of the six main centres, Auckland was the warmest during this past winter. Christchurch was the coldest, Tauranga had the most rain as well as being the sunniest. Dunedin was the driest, and Hamilton had the least sun.

There were only a few locations around the country which had near average temperatures, including Tararua, Kaikoura, and parts of Southland and Otago.