Identifying areas of high drought risk in southwest Western Australia

Drought is a significant natural hazard in Australia, associated with financial hardship and damage to soils and vegetation. With droughts expected to become more frequent and more severe as climate change progresses, it is increasingly important to identify drought risk and assess community-level drought resilience at the appropriate spatial, temporal and administrative scale for decision-making. Here, we have used spatial multi-criteria analysis (MCA) to identify regional priority areas for the implementation of drought resilience interventions or investment in southwest Western Australia (WA). The MCA method involves the systematic integration of spatial data of different magnitudes and units through standardisation and weighting, and the visualisation of aggregated data to a single parameter output map. The study region is home to the WA grains industry, the largest agricultural contributor to the economy and one of the regions most impacted by climate change in Australia to date, experiencing consistent reduction in rainfall and recurrent drought over the last several decades. We modelled drought exposure, sensitivity and adaptive capacity for the region, incorporating spatially explicit climate, environmental, social and economic data, and produced a suite of priority areas maps that were sense-checked against a participatory mapping process. The maps highlight the northern and eastern Wheatbelt of WA as areas at high risk from drought and have the potential to serve as a powerful tool for local-level drought resilience decision-making. Most of the data we used are publicly available, and the vulnerability framework applied allows for wide replication within and beyond southwest WA.