Megadroughts and pluvials in southwest Australia: 1350–2017 CE

Abstract Declining winter rainfall coupled with recent prolonged drought poses significant risks to water resources and agriculture across southern Australia. While declines over decades are largely consistent modelled climate change scenarios, particularly for southwest Australia, the significance of these is yet be assessed within context long-term hydroclimatic variability. Here, we present a new 668-year (1350–2017 CE) tree-ring reconstruction autumn–winter inland This record reveals that decline in Australia (since 2000 not unusual terms either magnitude or duration relative variability last seven centuries. Drought periods greater than those instrumental occurred prior 1900 CE, including two ‘megadroughts’ > 30 years eighteenth nineteenth By contrast, wettest decadal centuries after making twentieth century We conclude ~ does capture full scale natural risk droughts region likely much higher currently estimated.