Skip to main content
News_

Not all sunshine: the dangers of heatwaves

25 January 2019
3 experts explain the long weekend heatwave
Australia is set to swelter this long weekend, with the Bureau of Metereology predicting heatwaves across the country. Three experts from engineering and health sciences share how long, hot spells affect us and what they mean for our health and public infrastructure.
Heatwaves are more likely to affect the very young, elderly and those with chronic health conditions.

Heatwaves are more likely to affect the very young, elderly and those with chronic health conditions.

1. Mechanical infrastructure is negatively impacted by long periods of heat

Engineering expert from the University of Sydney's School of Aerospace, Mechanical and Mechatronic EngineeringPaul Briozzo, says heatwaves can affect the functioning of machinery in several ways.

“In terms of mechanical infrastructure, heatwaves or a prolonged period of increased temperature in the operating environment of machinery can have two detrimental effects. The first is weakening of materials that are susceptible to creep such as polymers, magnesium alloys and even some grades of aluminium. Increasing temperatures lower a material's ability to carry loads and the overall design life,” he explained.

“Heatwaves also have a second detrimental effect on machinery by lowering their efficiency. Machines such as automobiles and air conditioners work at a higher efficiency – known as Carnot efficiency – in lower temperatures. In the case of an automobile engine, on a cool winter's day at 15 degrees Celsius, an engine's Carnot efficiency is nearly 74%.

“In Sydney's West this coming long weekend, temperatures of 42 degrees are forecast. In this environment, the Carnot efficiency would drop to 71%. This drop in efficiency leads to lower fuel efficiency and higher fuel consumption and emissions which is not an ideal outcome for our environment.”

Just like us, assistance animals and pets need access to water and shade when it's hot outside.

Just like us, assistance animals and pets need access to water and shade when it's hot outside.

2. Heatwave preparation is essential for those with disabilities and chronic health conditions

“Heatwaves can exacerbate certain health conditions and may lead to emergency situations,” explains Dr Michelle Villeneuve who leads the Disability-Inclusive Community Development initiative at the University of Sydney's Centre for Disability Research and Policy.

“In addition to the general recommendations issued by state emergency services agencies, people with disabilities and chronic health conditions should plan for how they will manage their health and support needs during heatwaves.

“People who receive support from assistance animals must also consider the animal’s needs, such as ensuring they have access to water and shade, and checking that surface and pavement temperatures are cool enough for them to walk on.

“There are online resources which can help people prepare for heatwaves and other emergencies, such as PREPARE NSW. We have designed videos and tools to enable people and their support networks to proactively plan the steps they should take in emergencies and how to minimise risks.”

3. Climate change will make heatwaves deadlier

Structural engineer and computational mechanics expert from the University of Sydney's School of Civil Engineering, Professor Abbas El-Zein believes climate change will increase the health risks associated with heatwaves, negatively impacting society's most vulnerable.

“Heatwaves are anything but blind killers," he warned. "They harm mostly infants and the elderly, those with cardiovascular or respiratory diseases, those most isolated socially and those without access to cooling relief because they either cannot afford it or because they live in poorly-designed dwellings with low thermal comfort.

“In other words, while we may view heatwaves as a natural phenomenon, the way they impact us is highly political. Climate change driven by fossil fuel is likely to make them deadlier and more frequent, so even their occurrence is not entirely natural.”

Related news