All signs point to months of hot, dry and dangerous weather conditions, and the risks to health should not be underplayed.
Six days into the spring of 2023 there was still a chill in the air in most parts of Australia.
While Brisbane scored a top temperature of 23C and Alice Springs was a balmy 26, the rest of the country’s capital cities couldn’t get out of the teens. Hobart was a chilly 13.
In Geneva it was 25C and World Meteorological Organisation secretary-general Professor Petteri Taalas was facing the media.
The Copernicus Climate Change Service had just revealed Earth had recorded its hottest three months on record. The year from January to August had been the second hottest on record behind 2016, when there was a powerful warming El Niño event.
“The northern hemisphere just had a summer of extremes – with repeated heatwaves fuelling devastating wildfires, harming health, disrupting daily lives and wreaking a lasting toll on the environment,” said Professor Taalas.
The news came as little surprise given the massive heatwaves and wildfires that gripped the northern hemisphere. Canada had its worst wildfire season on record, with about 76,000 square kilometres burned, blanketing the country in toxic smoke. Temperatures nudged 50 degrees in Europe and went above that in other places, including China and California.
Fast forward a couple of weeks and on 19 September, the Australian Bureau of Meteorology declared Australia to be in an El Niño climate system. Within hours of this, Sydney and parts of the central and mid-north coast of NSW were plunged into a three-day heatwave with temperatures of more than 30C.
That heatwave might have been relatively brief, but it gave a whiff of what summer is likely to look like this year, and the northern hemisphere’s horrific experience only adds fuel to the fear.
It’s an easy flashback to Australia’s Black Summer of 2019-20. We have lived through a covid pandemic and faced devastating floods in the years since then, but it is far from a distant memory.
Those fires that ripped through the country killed at least 34 people, burned more than 24 million hectares and destroyed more than 3000 homes and buildings. Not a single state or territory was left untouched by fire or toxic smoke.
Later that year there was a Royal Commission into the fires, with the final 594-page report published in October making 80 recommendations. Last month Federal Emergency Management Minister Murray Watt told the ABC Australia “is much better prepared for this coming season than we were heading into Black Summer”.
“We have implemented almost all of the recommendations of the Bushfire Royal Commission that were made to the federal government,” he said.
These included establishing one coordinated national emergency management agency, rather than two separate organisations, making more aircraft available for firefighting than has ever been seen in Australia.
The government convened a National Disaster Preparedness Summit in Canberra in September, involving representatives from more than 200 state and federal government agencies, emergency services, charities, community organisations and the private corporate sector.
While this bodes well for preparedness, the reality is that the health impacts of heatwaves and bushfires are almost impossible to contain.
An article in Nature Sustainability, published in 2020, examined the “unprecedented health costs” of smoke from the 2019-20 Australian megafires and estimated the related health costs to be $1.95 billion.
“These were driven largely by an estimated 429 smoke-related premature deaths in addition to 3230 hospital admissions for cardiovascular and respiratory disorders and 1523 emergency attendances for asthma,” the authors wrote.
“The total cost was well above the next highest estimate of $566 million in 2002–03 and more than nine times the median annual wildfire associated costs for the previous 19 years of $211 million.”
The AIHW also looked at health impacts from Black Summer in its report, Australian bushfires 2019-20: exploring the short-term health impacts.
The report revealed increases in admitted patient hospitalisations and emergency department presentations for respiratory conditions, such as asthma and chronic obstructive pulmonary disease (COPD), associated with increased bushfire activity.
Changes in hospitalisation rates for cardiovascular conditions, mental health conditions and burns, could also be observed at specific times associated with bushfire activity in some locations, while analysis of Medicare Benefits Schedule data also shows increases in mental health service use in some areas, coinciding with, or following, bushfire activity.
The statistics and research are an important part of the picture. But seeing the health effects of extreme heat and bushfire smoke firsthand, often when they have become a life and death situation, is another.
Dr Kimberly Humphrey is an emergency medicine specialist and public health/climate medical consultant in Adelaide. She has worked in an ED on days of extreme heat.
“I am extremely worried about what summer is going to look like. I am very much expecting we’re going to see a number of significant heatwaves,” she says.
She has seen patients suffering from heat illness along the continuum, right up to heat stroke, which is extremely severe and involves coma, seizures and other complications.
In the ED the more vulnerable groups are often over-represented. This includes people with chronic conditions, like heart disease, lung disease, kidney disease – “all of those things mean you don’t handle the heat as well”, she says.
“We see people who aren’t compensating on a hot day as they usually would, and they end up in an ED with a worsening of their already chronic disease,” she explains.
“We see increased mental health presentations. And part of that is the fact that a lot of medications people are on for mental health mean that their body doesn’t regulate the heat as well. So it can stop them adjusting their temperature, it can stop them sweating, it has a lot of implications, just in their ability to handle a hot day.
“And we also see we see an increase in violence. We see an increase in domestic violence – hot weather makes people more aggressive and more irritable.”
Dr Humphrey, who is also chair of the South Australian Doctors for the Environment Committee and a clinical senior lecturer at the University of Adelaide, says the heat brings complex situations that can make the delivery of emergency health services a challenge.
There have been days in South Australia when the airport tarmac has been too hot for planes to fly, making air retrievals almost impossible. And then there are the everyday Aussies who just find themselves at the mercy of the weather.
“One of the most striking patients I can remember was on a day that was probably about 46 degrees,” she recalls.
“I had a woman come in who was quite dehydrated, she had heat-related illness, and was really unwell. She had just walked for two hours to get groceries for her family, because she didn’t have a car, she didn’t have access to public transport, and she needed to feed her family.
“No degree of promotion we do about how you need to be cool will matter when her immediate need is feeding her family. But as a consequence of that she ended up in our emergency department with heat-related illness.”
Dr Humphrey doesn’t think we’re ready in terms of our health system preparation across the nation, nor is the public or health workforce educated and prepared.
“There’s a lot that’s been done, there are a lot of people working really hard in the health and climate space to prepare for these things, but we’re not there yet, and I think it’s going to be fairly significant for a lot of people,” she says.
Doctors play an integral role in improving preparedness for individuals – especially those with chronic health conditions like COPD, cardiac and respiratory conditions, diabetes and autoimmune diseases she says.
Discussing a patient’s chronic disease management plan is a good opportunity to have the conversation about how vulnerable they may be to the effects of heat and bushfire smoke.
“Having those conversations and an action plan before those things happen means you can sort of future proof and safety net people before the events occur,” she says.
“Hopefully, that will go some way to helping build community resilience and keep people safe and out of emergency departments.”
There are much bigger conversations that need to be had around the long-term impacts of these weather changes – like how to help people to have a safe place to go when it’s 40 degrees outside and there’s a bushfire in the neighbourhood. How do we keep the homeless and people living in poverty safe when they don’t have the means to cool their environment?
South Australian GP Dr Kate Wylie agrees. As executive director of Doctors for the Environment Australia, a GP in Tea Tree Gully, and chairperson of the RACGP’s Climate and Environmental Medicine Specific Interest Group she is keenly aware of the issues that will face primary healthcare practitioners and their patients this summer.
“This year, we’ve had the hottest temperatures ever recorded on our planet,” she says.
“So as summer comes in, we can expect all our heatwave records to get smashed, we can expect a really hot and dry summer. And that means the increased risk of heat-related illness and death. So that means things like heat exhaustion, and heat stroke, which is a medical emergency.”
She also sees chronic disease management plans as the natural way for doctors to be proactive with patients when it comes to educating them about the impacts of heat and smoke on health and what they can do about it.
“We can also educate all our patients on staying cool in the heat – don’t go out in the heat of the day, keep well hydrated, wear loose, light-coloured clothing and that sort of thing,” says Dr Wylie.
“If there’s a blackout, make sure people understand that water is their friend. On a hot day with a blackout, you keep your feet in a bucket of water, you get in the bath, or you put a cold washer on the back of your head, using the cooling effect of water to keep yourself cool.”
Medication adjustments could also be considered in some patients – for example, those on diuretics and anticholinergics on hot days. And it should never be assumed that people automatically know the signs of heat stroke.
“If you’re having a funny turn, and it’s 34, and you’ve had a hot night, is it the heat? You have to have a low threshold for calling for help,” she says.
Dr Wylie says it’s important to recognise that this is a public health issue.
“We are hoping that there will be heat islands, like cool places, cool refuges for people to go – that’s one of the things they did in Paris was create cool islands. We’d want to see that in Australia as well,” she says.
Air quality is a big issue for all Australians, especially during times of bushfire. As Dr Wylie explains knowing your local air quality index (AQI) is important for everyone.
“Normal is between nought and 50,” she explains.
“Anything above 300 is hazardous for everybody. And everybody should stay inside. In Black Summer in Sydney, there were readings of 516 and those sorts of numbers.”
She advocates for everyone downloading an app to monitor their local air quality, and investing in good quality facemasks just in case people have to go outside when the air is toxic.
Another cohort at risk from extreme heat are pregnant women and their unborn babies.
University of Western Australia Associate Professor Caitlin Wyrwoll is leading a group of researchers who this year received a $3.34 million grant to explore the impact of heatwaves on health during pregnancy.
The research team includes investigators from the University of Western Australia, Telethon Kids Institute, Curtin University, Menzies School of Health Research, Australian National University, University of Sydney, University of Melbourne and Queensland University of Technology.
The funding is part of a global project funded by the Wellcome Trust to advance understanding of the biological vulnerability of pregnant women and babies to extreme heat.
“Pregnancy is the most physiologically dynamic process that the human body experiences and is a time of the life-course which is particularly vulnerable to heat exposure,” Professor Wyrwoll says.
“While heatwaves are proposed to increase pregnancy complications, the underlying physiological changes, specific climate zone risk factors and who is most at risk remain vague.”
Professor Wyrwoll says there’s a lot of evidence and epidemiological studies emerging about the associations of heatwaves, particularly with preterm birth.
“But there’s also suggestions of other contexts like foetal growth restriction and stillbirth and even miscarriage, but the data is limited,” she says.
“It’s exciting. We’re going to add a lot of understanding to the field in the next five years.”
One of the theories is that heat increases blood flow to the skin to try and cool the body, which may be redirecting blood flow away from the placenta, and therefore that has implications for placental function, and then fetal outcomes, she says.
There is also potential for altered endocrine responses leading to elevations in factors such as cortisol, and then other pathways, which could perhaps lead to changes in oxytocin and prostaglandins, which would then have implications for premature labour.
“Then you’ve got the added consideration of people who have pregnancy complications, such as diabetes, and preeclampsia and hypertension,” she says.
“There is some evidence to suggest that if you’re pregnant, hot and dehydrated, that affects things further in terms of the endocrine response, ultimately leading to uterine contractility, but again, it is still very vague.”
Climate change is upon us, and the looming summer is just the first of many more to come, says Dr Wylie.
“We can see our world changing around us. Now. The photos, the stories coming out of the northern hemisphere this past summer have been absolutely terrifying,” says Dr Wylie.
“We saw those people on the beach and on the islands of Greece, we read some of the incident reports about heat-related deaths in India, with lots of people dying. And it’s coming for us now. There has been historically a sense of complacency in the sense that we have more time.
“But now it’s knocking on our door.”
