Effects of climate change on New Zealand design wind speeds

Abstract

This study aims at (i) analysing the gust wind records of four meteorological stations across New Zealand for 1972-2017; (ii) investigating whether or not the long-term wind gust series have changed significantly; and (iii) assessing the impact of these changes in the estimation of design wind speeds to ensure the safety and reliability of future structures. Historical hourly and daily gust wind speed series recorded at the four selected stations were subjected to a robust quality control and homogenisation protocol. The results demonstrated that the annual and seasonal trends in both magnitudes and frequencies of extreme winds were generally negative over the considered period. Therefore, based on the derived gust trends for these four stations, at this stage, it seems that the long-term gust wind speed trends are not likely to have a significant effect on New Zealand’s design wind speeds. Lastly, our findings were compared with gust wind speed trends in several other countries and with IPCC 5th assessment projections for New Zealand.