The Sensitivity of Australian Fire Danger to Climate Change

Global climate change, such as that due to the proposed enhanced greenhouseeffect, is likely tohave a significant effect on biosphere-atmosphere interactions, includingbushfire regimes. Thisstudy quantifies the possible impact of climate change on fire regimes byestimating changes infire weather and the McArthur Forest Fire Danger Index (FDI), an index thatis used throughoutAustralia to estimate fire danger. The CSIRO 9-level general circulation model(CSIRO9 GCM)is used to simulate daily and seasonal fire danger for the present Australianclimate and for adoubled-CO2 climate. The impact assessment includes validation ofthe GCMs daily controlsimulation and the derivation of ‘correction factors’ which improve theaccuracy of the firedanger simulation. In summary, the general impact of doubled-CO2is to increase firedanger at all sites by increasing the number of days of very high and extremefire danger.Seasonal fire danger responds most to the large CO2-induced changesin maximumtemperature.