Clouds illuminated at sunrise over the Pacific Ocea,n viewed from the southern cliffs of Bondi Beach, Sydney on 4 March 2023.

HeatWatch uses data from the Bureau of Meteorology and CSIRO to show the increasing number of hot days we are already experiencing around Australia, and how many more we can expect as the world gets hotter, primarily due to fossil fuels.

Extreme heat, including heatwaves, impacts every aspect of our lives. It makes outdoor activities including sports, enjoying nature, and even socialising more difficult, less enjoyable and potentially dangerous. It increases the risk of fires. It is a serious health and safety risk to the millions of Australians who work outdoors or in un-air-conditioned spaces, such as construction, trades, and many others. It is also a threat to our precious ecosystems and our economy.

HeatWatch charts show the increase in hot days over various thresholds over recent years (red line). The charts cover temperature thresholds that considered extreme from a human health perspective; 35, 37 and 40 degrees Celsius. What is considered extreme varies between regions with people’s capacity to acclimatise.

The charts also show the increase in hot days we can expect in the future if we continue our dependence on fossil fuels (in red) compared to if we act decisively and stop new fossil fuel projects (in green). The shading shows a range of the projected average amount of days each year over these thresholds. We also examine minimum night-time temperatures, because it is important for our health to be able to cool off over-night.

The bad news is that major fossil fuel producing countries like Australia are still approving massive new coal, gas and oil projects. Australia is the world’s fifth largest fossil fuel producer and third largest exporter, with over 100 new fossil projects under development including gas mega projects like Woodside’s Burrup Hub, fracking in the Northern Territory, and at least 50 new coal projects. Australia also has a record of undermining global efforts to end fossil fuels, including calls by our Pacific neighbours to phase out fossil fuels. Without urgent action, the future is likely to resemble the red projections.

The good news is that if we stop approving new fossil fuel projects the amount of extreme heat days will stop increasing and eventually decline over coming decades, as seen in the green projections.


December 2023

November 2023

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