Southern Australia's rainfall is highly variable and influenced by factors across scales from synoptic weather to large-scale circulation and remote climate modes of variability. Anthropogenic climate change and natural variability modulate these factors and their interactions. However, studies often focus on changes in selected parts of the climate system with less emphasis on the system as a whole. As such, it is difficult to gain a complete understanding of how southern Australia's rainfall responds to broad-scale changes in the climate system. We step through the existing literature on long-term changes in synoptic-to-large-scale atmospheric circulation and drivers of climate variability to form a more complete story of rainfall changes across southern Australia. This process reveals that the most robust change is the observed winter decline in rainfall as it is consistent with several changing climatic factors: decreasing rainfall from weather systems, strengthening subtropical ridge, poleward shifts in the Hadley Cell and the Southern Annular Mode, and increasing frequency of positive Indian Ocean Dipole events. In other seasons, particularly summer, changes in atmospheric circulation and drivers may not agree with observed rainfall changes, highlighting gaps in our knowledge of atmospheric dynamics and climate change processes. Future work should focus on research across temporal- and spatial-scales, better understanding of jet interactions, the influence of stratospheric processes on the troposphere, and instances of contrasting trends in drivers and southern Australian rainfall changes.

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可以解释澳大利亚南部降雨量减少吗？对可能的驱动因素的回顾

南澳大利亚的降雨量变化很大，并受到从天气天气到大规模环流和远程气候变化模式的各种因素的影响。人为气候变化和自然变率调节这些因素及其相互作用。然而，研究往往侧重于气候系统选定部分的变化，而不太重视整个系统。因此，很难全面了解澳大利亚南部的降雨量如何响应气候系统的大范围变化。我们逐步浏览有关天气到大尺度大气环流的长期变化和气候变率驱动因素的现有文献，以形成更完整的澳大利亚南部降雨变化的故事。这一过程表明，最强烈的变化是观察到的冬季降雨量减少，因为它与几个不断变化的气候因素一致：天气系统导致的降雨量减少、副热带高压脊加强、哈德莱环流和南部环形模式的极移以及频率增加积极的印度洋偶极子事件。在其他季节，尤其是夏季，大气环流和驱动因素的变化可能与观测到的降雨变化不一致，这凸显了我们对大气动力学和气候变化过程的认识存在差距。未来的工作应侧重于跨时间和空间尺度的研究，更好地了解射流相互作用，平流层过程对对流层的影响，以及驱动因素和澳大利亚南部降雨变化趋势对比的实例。