Heatwaves and climate change


A heatwave is a period of unusually hot weather that can cause serious health effects. Heatwaves can worsen existing medical conditions and cause heat-related illness, which may be fatal. It can also affect community infrastructure, such as the power supply, public transport and other services.

Climate change: our biggest health challenge

The World Health Organisation describes climate change as the greatest threat to public health in the 21st century.

  • For 24-hour health advice call NURSE-ON-CALL on 1300 60 60 24.
  • For life-threatening emergencies call 000.

Heatwaves - who is most at risk?

Those most at risk during a heatwave are:

  • people aged over 65 years, especially those living alone,
  • people with medical conditions such as diabetes, kidney disease or mental illness
  • people taking certain medications
  • people with problematic alcohol or drug use
  • people with a disability who may not be able to communicate their discomfort or thirst
  • people who have trouble moving around
  • people who are overweight or obese
  • pregnant women, breastfeeding mothers, babies and young children
  • people who work or are physically active outdoors
  • people who live in the upper levels of buildings constructed before 1975.

Coping with the heat

  • Look after yourself and keep in touch with sick or frail friends, neighbours and relatives.
  • Drink plenty of water.
  • Keep yourself cool using wet towels, putting your feet in cool water and taking cool showers.
  • Spend as much time as possible in cool or air-conditioned buildings.
  • Close blinds during the day and open windows when there is a cool breeze.
  • Don't leave children, adults or animals in parked cars.
  • Stay out of the sun during the hottest part of the day. If you must go out, stay in the shade and take water.
  • Wear loose-fitting, light-coloured clothing.
  • Eat smaller meals more often and cold meals such as salads.
  • Make sure food that needs refrigeration is stored properly.
  • Avoid strenuous activity.
  • Watch or listen to news reports that provide more information during a heatwave.

Preparing for hot weather

  • Service your air conditioner before summer.
  • Stock up on food, water and medicines so you don't need to go out in the heat.
  • Store medicines at the recommended temperature.
  • Install awnings, shade cloth or external blinds on the sides of the house facing the sun.
  • Know where your closest 'cool places' are.

Preparing for power failure

  • The risk of a power outage is greater in extreme weather conditions. Make sure you have a plan in case of a blackout.
  • Plan what to do if a heatwave caused a blackout or disrupted public transport.
  • Ensure you have a torch, a fully charged mobile phone and battery-operated radio.
  • Consider your need for backup power, and don't rely on power as part of your bushfire preparedness plan.
  • Remember power outages can affect phones, radios and water pumps.

The Victorian Government website has more useful information.

Climate change - our biggest health challenge

We are already experiencing the impacts of climate change, including:

  • a decrease in average rainfall
  • a temperature increase of just over 1°C since 1910
  • increased fire danger in spring Increased severity and frequency of bushfires
  • more intense storm and flooding
  • increase in severe droughts.

In the future, Victoria can expect:

  • the average annual temperature to increase up to 2.4°C
  • double the number of very hot days
  • longer fire seasons with up to 60 per cent more very high fire danger days
  • more intense downpours
  • decline in alpine snowfall of 35 to 75 per cent
  • rising sea levels of around 24 cm.

Climate change and our health

  • More than 4,000 people were hospitalised, and 445 people died due to the smoke from the 2020 Black Summer bushfires.
  • Flooding has resulted in a tenfold increase in human-reported cases of Ross River Virus since 1993.
  • Ambulance Victoria had a 700 per cent rise in call-outs for cardiac arrest during the 2014 heatwave.
  • Healthcare professional are already seeing climate-related physical and mental health conditions in their community, such as heat stress and anxiety.
  • Exposure to bushfire smoke exacerbates heart and lung conditions, including asthma, and increases eye, nose and throat irritation.
  • Outdoor workers and manual labourers are at an increased risk of heat illness and heat stroke.
  • Bacteria like Salmonella thrive in the warmth, increasing our risk of food poisoning and gastrointestinal illnesses.
  • Warmer temperatures can lead to harmful algal blooms in water bodies, which threaten the safety of our drinking water and expose people to toxins.
  • Warmer temperatures can lengthen the pollen season.
  • Extreme weather can lead to psychological distress due to trauma, illness, loss of loved ones, destruction of property and displacement, and disruption of communities, goods and services.
  • Victorians feel frustration, sadness and outrage about climate change. These negative emotions, known as 'eco-anxiety' are felt more strongly by young people than any other population group.
  • The security and quality of our water resources are under threat, which affects overall food production.

Victorians rank health as the issue most important to them:

  • 90 per cent have not thought about how climate change may affect their health.
  • 1 in 3 Victorians are unaware that climate change will likely increase health risks.

For more information, view Climate Change - our biggest health challenge(PDF, 163KB).

More information