Australian summers are undergoing what scientists call a "total transformation," with a new study from World Weather Attribution revealing the country can now expect heatwaves every five years on average. The study's researchers say climate change made Australia's blistering heatwave in early January five times more likely, and there's an urgent need for the country to adapt to changed conditions. The warning comes as the country's south-eastern states prepare for what's forecast to be a prolonged, severe heatwave starting this weekend.