Extreme fire weather in Australia and the impact of the El Niño-Southern Oscillation

Abstract

This study investigates the influence of the El Niño-Southern Oscillation on fire weather in Australia, including its impact on the severity of seasonal fire danger and on extreme daily fire danger. The meteorological parameters of McArthur's forest Fire Danger Index (FDI) are analysed for composites of years of extreme high and low Southern Oscillation Index (SOI) during the period 1960 to 1992 using eight stations in different climatic zones. Results show that in southeast Australia and in central Australia, seasonal fire danger is higher in years of strong negative SOI and that the daily FDI has a significantly different distribution (with many more days with extreme fire danger). The Southern Oscillation has an opposite but small impact on the daily FDI distribution in the southwest of Australia. Daily minimum relative humidity (RH) is the fire weather parameter that is most strongly influenced by the Southern Oscillation. In southeastern Australia, RH is significantly lower in years of negative SOI.