Precipitation teleconnections with large-scale ocean–atmosphere oscillation systems provide useful information for water management. Here, we present a 7-year lag response in South Australia (SA) precipitation to the Southern Annular Mode (SAM) in a positive Interdecadal Pacific Oscillation (IPO) phase. This teleconnection between a positive SAM phase and increased SA precipitation, and vice versa, statistically consists of three sequential steps: a 27-season lag positive correlation between sea subsurface potential temperature (SSPT) to the south of SA and SAM, a zero-season lag positive correlation between sea surface temperature (SST) and SSPT, and a 2-season positive lag correlation between SA precipitation and sea surface temperature. Physically, this teleconnection seems to be associated with a supergyre circulation of the southern hemisphere oceans, which transfers SAM signal via subsurface potential sea temperature in the central south Pacific to the south of SA in 27 seasons during the positive IPO phase. Practically, this teleconnection provides a 7-year-lead drought precursor for rain-fed agriculture planning in SA. However, the teleconnection disappears in negative IPO phases. The oceanic pathway via the supergyre suggested in this study provides a basis to predict when this 7-year teleconnection may resume in the future based on observation and/or modeling.

具有大规模海洋-大气振荡系统的降水遥相关为水管理提供了有用的信息。在这里，我们提出了在南澳大利亚（SA）降水对正向年代际太平洋涛动（IPO）阶段的南部环形模式（SAM）的7年滞后响应。SAM正相和SA降水增加之间的这种遥相关，反之亦然，从统计学上讲由三个连续步骤组成：SA和SAM南部的海底潜在温度（SSPT）与SAM之间的27季节滞后正相关，零季节海面温度（SST）与SSPT之间存在滞后正相关，而SA降水与海面温度之间存在2季正相关。身体上 这种遥相关似乎与南半球海洋的超旋涡环流有关，在正IPO阶段，该环流在27个季节通过南太平洋中部的地下潜在海温将南极信号传输到南半球南部。实际上，这种远程连接为南非的雨养农业规划提供了领先7年的干旱先兆。但是，在负面的IPO阶段，远程连接消失了。这项研究中建议的通过超级旋涡的海洋路径为根据观测和/或模型预测未来7年的遥遥联系何时恢复提供了基础。这种远程连接为南非的雨养农业规划提供了领先7年的干旱先兆。但是，在负面的IPO阶段，远程连接消失了。在这项研究中建议的通过超级旋涡的海洋路径为根据观测和/或模型预测未来7年的遥遥联系何时恢复提供了基础。这种远程连接为南非的雨养农业规划提供了领先7年的干旱先兆。但是，在负面的IPO阶段，远程连接消失了。在这项研究中建议的通过超级旋涡的海洋路径为根据观测和/或模型预测未来7年的遥遥联系何时恢复提供了基础。