The report states that just sticking to current climate commitments by governments worldwide would see temperatures rise by 3C by 2090. Letting that happen "could have potentially catastrophic impacts" to Australia: Australia would be "warmer and drier with more frequent and violent extremes [of weather]".
One-in-100-year floods, like the ones just experienced, would be annual events. Huge bushfires would be frequent occurrences.
The average number of days each year above 35C in Sydney could quadruple by 2090. In Melbourne, 24 days could be above 35C compared to 11 now, and in Perth hot days could leap from 28 to 63.
But it's Darwin that could cop it the worst. It generally sees 11 days above 35C annually. With 2C of climate change, that could go up by 10 times to 111 days, or as many as 265 days under a 3C scenario.
Heatwaves in Queensland – that being under 1.5C of warming occurring three times a year and lasting for around seven days – would happen seven times annually and last 10 days under a 3C scenario.
The report suggests Melbourne and Sydney could regularly see 50C days. Already, Sydney's west has seen the mercury nearly touch that figure, leading it to be called out by the United Nations.
There are 10 actions the report recommends Australia knuckle down on. One of the main ones is a big swerve away from coal and investment in renewables and battery technology to store energy. Retraining people working in the fossil fuel energy industry, scaling up technologies that have less of an impact on emissions – such as electric vehicles – and preparing food production and supply chains for climate extremes are other recommendations.
Some of the worst aspects of a 3C warmer Australia might also be mitigated. Simply planting trees on suburban streets, for example, can bring surface temperatures down.