This technical report summarises three sets of data analysis based on monitoring of shallow reef biodiversity around the entire Australian continent. It is relevant to policy makers, managers and the research community. Key findings include a very clear impact of climate change on Australian reefs in the form of changing compositions of reef fishes and coral communities, and declines in some populations of temperate mobile invertebrates and tropical reef fishes. Relevant components have already been reported to the State of the Environment team in a national reefs case study and contributions to other relevant assessments. Follow up work using these results will be relevant to the Australian Government (e.g. with respect to threatened species and Australian Marine Parks) and the Great Barrier Reef Marine Park Authority. Improved models are required to quantify the relative impact of gradual warming and marine heatwaves on coral and rocky reef ecosystems.