Impacts and adaptation response of infrastructure and communities to heatwaves: the southern Australian experience of 2009

Impacts and adaptation response of infrastructure and communities to heatwaves: the southern Australian experience of 2009

From 27 January to 8 February during the summer of 2009, southern Australia experienced one of the nation's most severe heatwaves. Governments, councils, utilities, hospitals and emergency response organisations and the community were largely underprepared for an extreme event of this magnitude. This case study, 'Impacts and adaptation response of infrastructure and communities to heatwaves:
the southern Australian experience of 2009' was funded by The National Climate Change Adaptation Research Facility (NCCARF) under its Synthesis and Integrative Research Program. The study targets the experience and challenges faced by decision makers and policy makers and focuses on
the major metropolitan areas affected by the heatwave — Melbourne and Adelaide. This work resulted from collaboration between researchers from Risk Frontiers (at Macquarie University), Monash University, RMIT University and the University of Southern Queensland and was
coordinated by the Institute for Sustainable Resources, Queensland University of Technology. Broadly, the study examines the 2009 heatwave's characteristics; its impacts (on human health, infrastructure and human services); the degree of adaptive capacity (vulnerability and resilience) of various sectors, communities and individuals; and the reactive responses of government and emergency and associated services and their effectiveness. Barriers and challenges to adaptation and increasing resilience are also identified and further areas for research are suggested. This study does not include details of the heatwave's effects beyond Victoria and South Australia, or its
economic impacts, or of Victoria's 'Black Saturday' bushfires in 2009. Meteorological and climate characteristics
Key message : Compared to the 100–150 years of historical observations, the 2009 heatwave in southern Australia was exceptional — producing severe, extensive and prolonged
heat exposure. It was a major and unexpected heatwave in both Australian and international contexts, with extreme heat stress in the first phase and a bushfire disaster in the second phase of the heatwave. Climate change over the next 30–60 years will make such events more likely, and test the resilience of the expanding metropolitan areas, unless forewarning and other adaptation strategies are
successful. Southern Australian metropolitan regions have experienced severe and widespread heatwave events in the past (e.g. 1908 and 1939). Events in the first decade of the 21st century have been unusually intense, long-lasting and extensive; the 2009 heatwave was record-breaking. Maximum daily temperatures were 12 to 15 °C above the seasonal average of 28–32 °C for many consecutive days.
New daily maximum temperature extremes were observed for Adelaide (45.7 °C) and Melbourne (46.4 °C). Adelaide had eight consecutive days over 40 °C and Melbourne suffered an unprecedented run of three days above 43 °C. Night-time temperatures for both Adelaide and Melbourne were unusually high. Slow-changing synoptic conditions maintained a very hot air mass over south-eastern Australia. This heat build-up was made worse by exceptionally low surface moisture resulting from an extended drought over the previous month and years. There was also little temporary relief provided in these coastal cities by sea or bay breezes.

© Queensland University of Technology, Monash University and University of Southern Queensland incorporating contributions from Access Macquarie Limited and Royal Melbourne Institute of Technology 2010. NCCARF Publication 13/10.