Key Takeaways
- 2025 was the fourth-hottest year on record in New Zealand, with most regions experiencing temperatures above average.
- The highest annual average temperature was recorded in Leigh, North of Auckland, at 17.7 degrees.
- Atmospheric carbon dioxide levels continued to rise, surpassing 423 ppm at the Baring Head monitoring station.
- November was the warmest on record, with most of the country experiencing temperatures more than 1.2 degrees warmer than average.
- Sea temperatures were also on the rise, with local sea surface temperatures remaining above normal for most of the year.
Introduction to the 2025 Climate Report
The 2025 annual climate report released by Earth Sciences New Zealand (ESNZ) reveals that the country experienced its fourth-hottest year on record. The report, which analyzed data from various weather stations across the country, found that most regions were hotter than average by between 0.51 and 1.20 degrees. However, some areas, such as Northland and Bay of Plenty, were significantly hotter, with temperatures exceeding 1.2 degrees above average. The report highlights the impact of human-induced climate change, with four of the five warmest years on record occurring since 2021.
Temperature Records
The report notes that the highest annual average temperature was recorded in Leigh, North of Auckland, at 17.7 degrees, followed by Kaitaia at 17.1 degrees, and Whangaparāoa at 16.9 degrees. The highest air temperature of the year was 35.6 degrees, recorded at Kawerau on December 7. This was followed by 33.8 degrees at Napier on December 8, and 33.7 degrees at Ettrick on February 16. The report also found that Auckland was the warmest of the six main centers, while Tauranga was the sunniest and wettest. Christchurch and Dunedin were the equal-coolest, with Dunedin also being the driest and least sunny.
Carbon Dioxide Levels and Climate Change
The report highlights the continued rise in atmospheric carbon dioxide levels, which surpassed 423 ppm at the Baring Head monitoring station. This increase is attributed to human-induced climate change, which has resulted in four of the five warmest years on record occurring since 2021. The report notes that the nationwide average temperature was 13.51 degrees, with most regions experiencing temperatures above average. The data suggests that climate change is having a significant impact on New Zealand’s climate, with rising temperatures and changing weather patterns becoming more frequent.
Regional Variations
The report found that some regions were much wetter than usual, with areas such as Nelson, Marlborough, and Banks Peninsula receiving 20 to almost 50 percent more rain than usual. In contrast, the North Island and the northern part of the South Island experienced below-normal soil moisture levels during the first quarter of 2025. However, by the end of winter, moisture levels had returned to normal, only to dry out again in some eastern parts by the end of November. The report also notes that Taranaki received the highest annual sunshine, with 2743 hours recorded at New Plymouth, followed by the Nelson region with 2672 hours recorded at Richmond.
Sea Temperatures and Other Findings
The report found that local sea surface temperatures were relatively warm, remaining above normal for most of the year. November was the warmest on record, with sea surface temperatures being the highest ever recorded. The report also notes that the highest confirmed wind gust for 2025 was 252 km/h at Cape Turnagain on the east coast of the North Island on October 21. The coldest air temperature was recorded at Mt Cook airport on June 8, at -12.9 degrees Celsius. The wettest location was Cropp River at the Waterfall, which recorded 10,951 mm of rainfall, followed by another gauge on the Cropp River at Cropp Hut, which recorded 9925 mm.
Conclusion
The 2025 annual climate report released by Earth Sciences New Zealand provides a comprehensive overview of the country’s climate during the year. The report highlights the impact of human-induced climate change, with rising temperatures, changing weather patterns, and increasing carbon dioxide levels. The data suggests that New Zealand is experiencing more frequent and severe weather events, with significant implications for the environment, economy, and society. The report’s findings emphasize the need for continued monitoring and research into climate change, as well as the development of strategies to mitigate its impacts and adapt to a changing climate.