An extreme heat event in 2050 could kill more than 1000 Brisbane people in a few days unless emergency response strategies are significantly improved, according to a new report on heatwaves.
Produced by Price Waterhouse Coopers in collaboration with the Department of Climate Change and Energy and Efficiency, the publication claims heatwaves kill more Australians than any other national disaster, including floods and bushfires.
And although Melbourne currently has the highest rate of death due to extreme heat, demographic projections reveal Brisbane as the capital most at risk of heatwave deaths in the future.
According to the report, the annualised average mortality impact of heat events was about 80 excess deaths across all capital cities, based on the 2011 population.
Outlining the research presented in Protecting Human Health and Safety During Severe and Extreme Heat Events: A National Framework, PWC principal Roger Beale said Brisbane's growing, ageing population made the city more vulnerable.
The impacts of urbanisation and climate change would also contribute to the morbid impact of heatwaves, broadly defined as periods when unusually high temperatures arise relative to space and time.
Mr Beale said Bureau of Meteorology modelling showed extreme heat events were expected to occur more often and with greater intensity in the future, particularly in the southern regions of Australia.
But the relative infrequency of similar events in Queensland would likely contribute to the morbid severity of heatwaves in the state, Mr Beale said.
“Brisbane seems to be more sensitive; the events are less frequent, and so people are less used to it,” Mr Beale said.
The city's last significant heat event was in February 2004, when temperatures peaked at 41.7 degrees and claimed the lives of 12 Queenslanders, significantly less than the hundreds expected to die in the future.
“This is not just about deaths,” Mr Beale said.
“For example, in the February 2004 Queensland heat event, schools and businesses were hit hard and public transport was disrupted.”
“Australia needs a national heatwave plan. The economic and social and costs of extreme heat events are significant and potentially avoidable."
Although the 2004 event saw the Queensland government take steps towards a heatwaves strategy, Mr Beale said there was still much work to be done, including improving social attitudes regarding dealing with very hot weather.
He said the “harden-up” aspect of the Australian psyche contributed to a disregard for the severity of extreme heat, along with a lack of community engagement with the problem.
“If there's a flood coming down the street, everyone is affected by it, but when it comes to extreme heat, it could just be the very lone overweight or elderly person in the older, poorly insulated Queenslander house who suffers,” Mr Beale said.
“We need to look at how we address these events at a government level, but also at a community level through the use of social media.
“Heatwaves are a silent killer – they rarely get the media attention deserved because there are no great pictures; the deaths are usually suffered alone, and they're awful, suffocating experiences.”
For the development of this report, PWC formed an advisory group which included the Bureau of Meteorology, federal and state government agencies and the private sector.
PWC worked with BOM data and conducted actuarial analysis which looked at temperatures across Australia on every day since 1958 and matched those with deaths over the same period.
BOM research and systems deputy director Neville Smith said the report was a valuable contribution to the discussion about how best to approach the enormous challenge of planning for extreme heat events.