Introduction: Heatwaves are one of the most important climate-related risks for Australians.
The extreme heat in Melbourne that plagued the 2014 Australian Open Tennis Tournament and the record-breaking heat in large areas of Queensland this summer reminded us of the risks that heatwaves pose. Coming on the heels of a record-breaking summer of 2012/2013, this summer’s heat is part of a longer- term trend towards hotter weather. The link between climate change and more extreme heatwaves is clear.
This report begins by exploring the long-term observations of hot weather to show how the nature of heatwaves is changing—their length, their frequency, their intensity and when they are occurring. We then describe what these trends mean for Australians—their impacts on our health and well-being, infrastructure, agriculture, biodiversity, and natural ecosystems. But heatwaves don’t occur in isolation from other factors and their interactions with events such as droughts can exacerbate the effects of extreme heat. Finally, we take a look at the future—how the risks of extreme heat change as the Earth warms further, and what we need to do to stabilize the climate and avoid the more severe projections for future heatwaves.