People living in cities, especially those with low income, low education and some health conditions, are at a higher risk of dying than people in regional areas, the studies found.
The research analysed more than 2000 suburbs and found city-dwellers were at higher risk in all Australia’s capital cities, which are home to 70 per cent of the population.
PhD candidate Patrick Amoatey from the University of Queensland said the study – the largest of its kind conducted in Australia – found people living in cities were at higher risk of death during extreme temperature events because of the “heat island effect” of heat-absorbing surfaces like roads, buildings and railway lines.
Even with low-intensity heatwaves there was a strong association with deaths.
He said the Heatwave Vulnerability Index, used by other countries, could be used by authorities to predict an increase in ambulance callouts and mortality rates during heatwaves in Australia.
“We already have useful tools and State-based action plans to reduce the impact of heatwaves, but we believe a vulnerability index could help supplement this to help communities plan and build resilience.”
A heatwave is a period of three consecutive days where the maximum temperature is in the top five per cent for that area.
Associate Professor Nicholas Osborne said these events are likely to happen more often in the future.
“Our results suggest heatwaves with associated periods of higher mortality will occur more often than they did in the past,” Associate Professor Nicholas Osborne said.
He said the research was now focused on helping communities prepare themselves.
In a separate study, researchers from UQ and The Australian National University analysed mortality rates during an extreme heatwave in Victoria in January 2009, with decades of climate data.
An estimated 374 excess deaths occurred in Victoria during the five-day event, with maximum temperatures reaching 12 – 15 degrees above normal.
“Human-induced climate change had increased the excess heatwave-related mortality in the 2009 event by 20 per cent,” Dr Osborne said.
“These findings were in line with other research that shows heat-related deaths are increasing due to human-induced climate change.
“From a public health perspective, our studies and further research can provide guidance on the need for adequate health infrastructure and workforce that might be needed to cope with higher demand for health services during heatwaves.”
