Substantial increases in the likelihood of extreme fire weather events for fire-prone ecosystems in Australia

We evaluated the influence of climate change on fire weather in Australia using the McArthur Forest Fire Danger Index (FFDI) and climate simulations from an ensemble of dynamically downscaled CMIP6 projections. Extreme FFDI events were assessed under a range of Global Warming Levels (GWLs) using the Generalised Extreme Value (GEV) distribution, with a focus on southeast Australia’s wildfire prone eucalyptus forests. The magnitude and frequency of extreme FFDI events are projected to increase substantially, particularly in southern Australia. For the eucalyptus forests of southeast Australia, 20-year and 50-year return interval 7-day FFDI events (i.e. weekly average FFDI extremes) are projected to become approximately 2.1 and 2.5 times more likely under 3 °C of global warming. The increases are most notable for the eucalyptus forests of Tasmania, with projected 20-year and 50-year return interval 7-day FFDI events becoming approximately 3.2 and 4.1 times more likely at 3 °C GWL.