New Zealand’s winters getting shorter
14 New Zealand’s winter has shortened by a month over the last 100 years, with the season of very low temperatures, frosts and snow starting significantly later in the year and ending earlier.
Brett Mullan, from the National Institute of Water and Atmospheric Research, compared records from two 30-year periods over the last century to see if New Zealand was experiencing the same contraction of winter weather noted in other parts of the world.
Mullan defined a winter’s day as one in which the daily average temperature was below 9C. He examined temperatures between 1909 and 1938, and 1987 to 2016, from seven representative regions. He found there was an average of 100 days per year between 1909 and 1938 when the temperature was below 9C, compared with only 70 days per year between 1987 and 2016.