Aotearoa New Zealand's 21st-Century Wildfire Climate

Abstract

Wildfire is a highly variable natural phenomenon, yet despite this, climate change is already making wildfire conditions measurably worse around the world; however, detailed knowledge about Aotearoa New Zealand's wildfire climate is currently limited. This study blends weather observations with regional climate model projections to assess Aotearoa New Zealand's 21st-century wildfire climate. We find that in the 21st-century, the emergence of a new—more severe wildfire climate will occur. Detailed analysis of observed and simulated wildfire weather finds that “very-extreme” wildfire weather conditions matching the levels observed in Australia's 2019/2020 “Black Summer” bushfires are possible in regions formerly unaffected. While the extent of emergence is dependent on future emissions, the frequency of very-extreme conditions for the areas affected can occur at any time and is independent of projected 21st-century climate changes. Our findings have significant implications for many rural fire authorities, forest managers and investors, and climate mitigation and afforestation programs.