This indicator provides data for the number of warm days (daily maximum temperature above 25 degrees Celsius) for the 30 sites across New Zealand from at least 1972 to 2022.
Global average temperatures have increased by around 1 degree Celsius in the last century, almost certainly a result of high levels of atmospheric greenhouse gases emitted from human activities. While this change may seem small, relatively small changes in our climate can have big effects on our environment (Ministry for the Environment [MfE] & Stats NZ, 2019).
The number of warm days change from year to year in response to variable weather patterns and climate drivers. Climate models project we may experience more warm extremes in the future (IPCC, 2021). According to the WMO (2016) a decrease in cold days and nights and an increase in warm days and nights can have major implications for human health, agricultural production, and ecosystems.
Variables:
site: NIWA monitoring site
n_days: Number of days
period_start: Start of the period where the number of days were counted
period_end: End of the period where the number of days were counted
lat: Latitude
lon: Longitude
site_simple: site without macrons
References:
Intergovernmental Panel on Climate Change. (2021). Climate Change 2021: The Physical Science Basis. Contribution of Working Group I to the Sixth Assessment Report of the Intergovernmental Panel on Climate Change (V. Masson-Delmotte, P. Zhai, A. Pirani, S. L. Connors, C. Péan, S. Berger, N. Caud, Y. Chen, L. Goldfarb, M. I. Gomis, M. Huang, K. Leitzell, E. Lonnoy, J. B. R. Matthews, T. K. Maycock, T. Waterfield, O. Yelekçi, R. Yu, & B. Zhou, Eds.). Cambridge University Press.
https://www.ipcc.ch/report/ar6/wg1/
Ministry for the Environment & Stats NZ. (2019). New Zealand’s Environmental Reporting Series: Environment Aotearoa 2019 (Publication No. ME 1416). https://www.mfe.govt.nz/publications/environmental-reporting/environment-aotearoa-2019
World Meteorological Organization. (2016). Hotter, drier, wetter. Face the future. WMO. https://public.wmo.int/en/resources/world-meteorological-day/previous-world-meteorological-days/hotter-drier-wetter-face
