Attribution of extreme events to climate change in the Australian region – A review

Extreme event attribution is a rapidly growing field of climate science with important implications for public and government understanding of human-induced climate change. However, there is substantial variation in how well events can be attributed to human-induced climate change, depending on the nature of the event. Focusing on Australia: at one end of the scale, large-scale heat events on both the land and in the ocean are well suited to attribution studies because climate models simulate them reasonably well, there are high-quality observations available and our understanding of the processes that lead to extreme heat events is reasonably well developed. At the other end of the scale, very important phenomenon such as changes in east coast lows, severe convective storms and long-term droughts are less well observed, are beyond our current capability to robustly simulate in climate models and the complex mechanisms that lead to intensification are not well understood. Thus, some important extreme events can be linked to human-induced climate change, with a high degree of confidence, while others cannot. We review the state of the science relevant to event attribution with a focus on Australia. We highlight where progress can be made, focusing on observations, physical understanding, and realistic climate modelling.