The contribution of atmospheric features to mean and extreme precipitation across Australia

Abstract

Understanding how precipitation is associated with the atmospheric features is critical for comprehension of processes underpinning water resource management and extreme events leading to natural disasters. This study evaluates how the key atmospheric features of Australia are associated to total and extreme precipitation across eight Australian natural resource management regions and how they vary seasonally. To this end, we apply the Multi-Object Analysis of Atmospheric Phenomena algorithm to two reanalysis datasets—ERA5 and BARRA-R2—and assess feature frequency and precipitation contributions for the period 1980–2020. Results show strong regional and seasonal differences. Precipitation often occurs together with jet streams, mesoscale convective systems, atmospheric rivers and cyclones. Extreme precipitation is closely linked to mesoscale convective systems and cyclones in northern Australia, particularly during warm season, while in southern Australia it is primarily driven by jet streams, cyclones, and atmospheric rivers, noting uncertainties for fronts. Trend analysis reveals opposite shifts in jet streams, mesoscale convective systems and atmospheric rivers across regions and seasons, with increases over southern and central regions during warm season and decreases for east, south and west regions during cool season. This study provides the first multi-feature assessment of atmospheric drivers of Australian precipitation, using a complementary approach to previous studies, offering valuable insights for climate adaptation and water resource management.