2021 blows past 2020 to take warmest winter record
This winter has entered the record books at the warmest, with temperatures across the country 1.3 degrees Celsius warmer than average. Its the second time the record has fallen in two years, according to Niwa measurements. Last year was 1.1C above normal. The spell is likely to continue into spring, with above average temperatures very likely right across the country. READ MORE: * It may feel chilly, but this winter is on track to be the warmest ever * Rain falls at the summit of Greenland Ice Sheet for first time on record * New Zealand weather: Expect the new normal for temperatures to get warmer This winters record warmth was a confluence of climate change and shorter-term conditions in the Pacific Ocean, according to forecasters. The ocean experiences cycles of El Nino and La Nina, which affect weather patterns from Aotearoa and Australia right across the Pacific to South America . La Nina has been the driving force over the last two years, bringing northerly wind flows and hotter sea temperatures to New Zealand. It particularly influenced the start of winter. The month of June was the warmest on record, said Niwa meteorologist Nava Fedaeff. We had multiple bouts of high pressure, and settled weather. So that leads to sunny conditions that can lead to cooler nights, but that didnt really occur. This translated into warmer readings at Niwas seven temperature stations which have been tracked since 1909 dotted around the country. The winter warmth was consistent: 76 sites had record or near-record high readings. On August 24, the mercury hit 23C in Akaroa. La Nina produced a similar one-two punch of warm winters in 1970 and 1971. The winter of 1970 became the warmest on record, broken in 1971. However, with atmospheric carbon dioxide levels rising, these years now sit way down the list: 1970 is in 18th place and 1971 is number 13. The two 1970s winters are now considered average, Fedaeff said. These similar winters, decades apart, show us that there are key natural ingredients to getting a warm winter but adding climate change to the mix is like taking the same recipe and swapping plain flour for self-raising. As well as being warm, the country recorded intense rainfall. Several storm systems known as atmospheric rivers dumped large amounts of rain on parts of the country. These were likely influenced by conditions in the Indian Ocean, which created more moisture in the tropics. Most of Northland, southern Manawatu-Whanganui, the Kapiti Coast and Wellington had above average rainfall, as did large areas of the upper and western South Island. Buller experienced severe flooding in July. Other parts of the country including western Northland, Auckland, parts of Gisborne and Hawkes Bay and southern Canterbury were drier than normal. Stay on top of the latest climate news. The Forever Project's Olivia Wannan will keep you in the know each week. Sign up here .