Extreme Heat

Due to climate change, Melbourne is experiencing more hot weather and heat wave events than ever before. In Melbourne, we currently average 11 days greater than 35 degrees and expect this to rise to 16 days by 2050.

Known as a ‘silent killer’, extreme heat causes more fatalities than all other natural hazards combined. Heat is not as visible or visually shocking as other climate hazards such as flooding or bushfires. This means it does not have the same awareness, understanding, or management attention as that of other hazards. 

There is a public misperception when it comes to the issue of extreme heat risk. Many people do not think heat poses a risk to them – we want to raise awareness of the fact anyone can experience heat stress, particularly those with an existing vulnerability.

Public misperceptions of extreme heat risk include:

1. Although heatwaves may have claimed many more lives in Australia than any other natural hazard, they do not elicit the same kind of perception and response that bushfires and other comparatively more dramatic hazards do. The trouble with heatwaves, then, is in part a conceptual, cultural, and historical one. This hazard has been experienced by most Australians, and most people have, over many years, been able to adapt to its threat and manage its risk. Through these experiences, arguably, heatwaves have been rendered a ‘normal’ hazard. 

2. A survey of more than 400 Australians in South Australia found less than 37% of respondents cumulatively agreed and strongly agreed that they were personally at risk from heatwaves.

3. A City of Melbourne survey found that while 80% of respondents are concerned or strongly concerned about the health risks heat poses to others in their community, only 50% of respondents are concerned about the health risks heat poses to themselves.

Challenges faced when trying to communicate about heat risk:

1. You can’t ‘evacuate’ from heat. When it settles, the population has little option but to wait it out. As the high temperature lingers, the death toll rises. 

2. When contrasted with other natural hazards such as cyclone, bushfire and flood, heatwaves are directly experienced by a large percentage of the Australian population far more frequently.

3. Heatwaves don’t have visually shocking imagery as bushfires, floods and other extreme weather events. Communicating about heatwaves is made more difficult because it is inherently an abstract risk. 

Impacts of extreme heat:

1. Extreme heat days and heatwaves have significant economic and health impacts on the city. People living in the city are at greater risk during heat events as a result of the urban heat island effect, which shows that urban areas are 3 to 8 degrees Celsius warmer than rural areas.

2. Exposure to extreme heat impacts infrastructure, businesses, plants, animals and people, and can cause heat exhaustion, heat stroke and death.

3. During extreme heat events we can experience increases in heat-related illness, power outages, and disruption to transport services and outdoor events.

4. Most vulnerable groups:

• Women who are disproportionally impacted by climate change

• CALD communities

• Youth and international students

• Visitors to the municipality

• Elderly