Forecasting fire activity in Victoria, Australia, using antecedent climate variables and ENSO indices

Abstract

Climatic variability alters precipitation and temperature patterns globally, and presumably has an effect on regional fire regimes, yet relationships between climate variation and bushfire activity are poorly understood in many fire-prone regions. Such relationships may facilitate forecasting of the potential fire risk for an upcoming season. This paper reviews the interaction between the El Niño–Southern Oscillation (ENSO), and the weather and fire activity in the fire-prone state of Victoria, Australia. Linear correlations were used to analyse the relationships between ENSO indices, spatially averaged climate variables and fire activity in Victoria from 1972 to 2012. Data were analysed using monthly and seasonal averages and both antecedent and concurrent relationships were explored. Significant relationships were identified between fire activity and climate variables, especially in September to November, the months immediately preceding the fire season. In order of strength, these climate variables are vapour pressure at 1500 hours, vapour pressure at 0900 hours, maximum temperature, rainfall and minimum temperature. Additionally, significant relationships between ENSO indices and fire activity were identified for this period, although these relationships were not as strong as those with climate variables. The potential exists to use ENSO indices and climate variables to forecast an upcoming season’s potential bushfire activity. This is the first study to analyse the ENSO–fire relationship specifically for Victoria and also the first to use Victorian fire activity data (rather than indices of fire weather) as a basis for the comparison with climate and ENSO.