Ambos feel the heat

Hannah Mason is Lecturer at James Cook University’s College of Public Health, Medical & Vet Sciences. She was the lead author of a study analysing heatwaves and emergency ‘Triple Zero’ (000) calls to the Queensland Ambulance Service from 2010–2019.

Miss Mason said heatwaves are a significant and growing threat to health and well-being and are expected to increase in severity, duration, and frequency due to climate change.

“Heatwaves increase the risk of heat stress-related conditions and exacerbate pre-existing conditions such as heart and renal disease,” she said.

Miss Mason worked with Professor of public health research Richard Franklin and researchers from the Queensland Ambulance Service and Queensland Health on the study, funded by the Queensland Department of Environment and Science.

She said the researchers found emergency ambulance calls to Triple Zero in Queensland increased on average by 12.7% during heatwaves.

“The effect was greatest during low-severity heatwaves (22.2%), followed by severe heatwaves (14.3%), and lowest during extreme heatwaves (1.2%). Those living in very remote areas and major cities were most impacted, along with those of low and middle socioeconomic status during low and severe intensity heatwave events,” said Miss Mason.

She said the finding that emergency ambulance calls were lower during extreme heatwaves may be attributed to risk perception and changes in behaviour.

“It’s possible Queenslanders are aware of the dangers of extreme heatwaves and mitigate risk by staying indoors during these events but are more willing to ignore risks and carry out their usual outdoor activities during low-severity heatwaves. Adaptive behaviours during heatwaves need further investigation,” said Miss Mason.

She said post-heatwave effects continued for at least 10 days, and that ambulance calls remained higher than average during this time, although the first 3 days following a heatwave are of most concern.

“We think the lag effect found in this study may be because of high-temperature days following a heatwave event that do not meet the heatwave threshold but are still hot enough to have a physiological impact,” said Miss Mason.

She said heatwaves become disasters when communities are unable to effectively adapt, placing pressure on response agencies. The Queensland Ambulance Service recognises the need to meet the threat of a changing climate in their strategic plan (2022-2027).

“Heatwaves significantly increase ambulance callouts, so ambulance services must actively plan for, and prepare resources and personnel to address likely increases in heatwaves under a changing climate.

“Communities must be informed of the risks of heatwaves of all severities, particularly low severity, and the sustained risks in the days following a heatwave event.

Link to paper here.