Bushfire season in Australian indigenous seasonal calendars and associated drought trends

Climate-induced changes in rainfall and temperature across Australia exacerbate drought and bushfire risk which have detrimental impacts on flora, fauna, and water quality. Indigenous Peoples across Australia have recorded climate, environment, and biotic patterns in seasonal calendars, of which five are used to delineate approximate time windows associated with bushfire to demonstrate the necessity of weaving non-colonial and colonial knowledges for better understanding modern climate challenges. The bushfire season (October–March) was examined for variability and trends in the Standardised Precipitation Evapotranspiration Index (SPEI), the Southern Oscillation Index (SOI), and the Indian Ocean Dipole (IOD) historical data from 1950 to 2021. SPEI is an integrative measure of local land-atmospheric conditions and affords physics-based monitoring of drought conditions across large spatial scales, using temperature, precipitation, and potential evapotranspiration to evaluate moisture content in a region. Taken together, information gained from seasonal calendars, delineated bushfire and drought index relationships, demonstrated in the leading patterns of SPEI showing moderate correlations with SOI and sea surface temperatures, offer a rich portrait of salient knowledge to bushfire risk and, one that can be beneficially used in the context of braiding Indigenous and western knowledge to enhance climate adaptation.