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Southern China spring rainfall (SCSR) is significant for agricultural sowing and soil moisture accumulation before the rainy summer. A better prediction of the rainfall improves our ability to risk response to natural disasters. It is found that the SCSR can be promoted by multi‐year El Niño events through the high‐latitude pathway (HP) and low‐latitude pathway (LP). The long‐lasting El Niño warming heats the tropical troposphere persistently until the decaying spring, which strengthens the Arctic polar vortex and the mid‐latitude blockings. This HP is in favor of more southward transport of Rossby wave energy and cold air, resulting in strong ascending motions over southern China (SC) in spring. The multi‐year El Niño also induces an enhanced western North Pacific anticyclone and a secondary circulation transporting moisture to SC through the LP. The HP is more important in the early spring, while the LP dominates the heavy SCSR in the late spring. Plain Language Summary: Southern China (SC) experiences a period of rainy time in spring, with the rainband located from South China to the Yangtze River. The southern China spring rainfall (SCSR) is influential for agriculture and soil moisture accumulation before the flood season in summer. A better prediction of the SCSR improves our ability to risk response to natural disasters. El Niño‐Southern Oscillation (ENSO) is the dominant climate signal that exerts significant remote impacts, especially in East Asia. However, whether it can help to predict the SCSR is still unclear. In this study, we show that a particular type of ENSO event, the multi‐year El Niño, initiates remarkable impacts on the SCSR. The long‐lasting Pacific warming favors a HP that transports more cold air and wave energy southward to SC during the decaying spring. Moreover, it also strengthens the western North Pacific anticyclone and generates a meridional secondary circulation with low‐level moisture transport toward SC. The low‐latitude and HPs collaborate to generate strong ascending motions and water vapor convergence in SC, being responsible for the large SCSR. Thus, the remote climate impact of multi‐year ENSO events is distinctive from the other ENSO events. Key Points: Multi‐year El Niño enhances southern China (SC) spring rainfall through both the low‐latitude pathway (LP) and the high‐latitude pathway (HP)Long‐lasting tropical warming supports the HP which transports wave energy and cold air to SC and exerts ascending motionsThese ascending motions and moisture transportation by El Niño‐induced western Pacific anticyclone can be further intensified by the LP [ABSTRACT FROM AUTHOR]

This study examines the relationship between the Quasi‐Biennial Oscillation (QBO) and the variability of the East Asian winter monsoon (EAWM) in the Northern Hemisphere (NH) winter. Here, we consider the effects of QBO winds in the lower stratosphere at 70 hPa. It is found that during the period of 1958–2019, the EAWM in the early winter months (November–December) is weaker in the easterly phase of the QBO (EQBO) than in the westerly phase of the QBO (WQBO). During EQBO, the northerly monsoon flow is weakened, and anomalous warm temperatures occur over East Asia. Moreover, components of the EAWM circulation system, including the Siberian High, Aleutian Low, East Asian trough, and East Asian jet stream, are all weakened. Our further analysis suggests that the QBO may influence the EAWM directly via a subtropical pathway. The EQBO tends to weaken the East Asian jet stream and shift it poleward, and the changes in the East Asian jet stream lead to a weakened EAWM. The activities of planetary waves are also changed in association with the QBO. Examinations of individual zonal wavenumbers (WNs) of planetary waves in the SLP field reveal that WN 1 is strengthened while WNs 2 and 3 are weakened during EQBO. Specifically, the anomalous WN 2 leads to weakening of the Siberian High, Aleutian Low, and East Asian trough, and the anomalous WN 3 reduces the pressure gradient between the East Asia landmass and the western Pacific. The changes in WNs 2 and 3 associated with the QBO play a dominant role in anomalous EAWM. [ABSTRACT FROM AUTHOR]