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The interdecadal variability of tropical cyclone precipitation (TCP) over the western North Pacific (WNP) has not been thoroughly explored in previous studies. Here, we show that the TCP variations are modulated by both the Atlantic Multidecadal Oscillation (AMO) and Interdecadal Pacific Oscillation (IPO) as evidenced by reanalysis data and model experiments. A clustering analysis of tropical cyclone tracks shows that the AMO dominates a dipole pattern of TCP anomalies in the South China Sea and along the coastal eastern China. Meanwhile, the IPO dominates TCP over the southeastern WNP. Further analyses show that the AMO, particularly its extratropical component, affects TCP over the WNP by triggering an eastward‐propagating Rossby‐wave train, resulting in a pair of anomalous gyres over the WNP. Contrastly, the IPO modulates TCP by stimulating tropical circulation anomalies via the tropical pathway. These findings shed light on improving near‐term TCP forecast and its regional influence on East Asia. Plain Language Summary: Tropical cyclone precipitation (TCP) is a topic of great concern owing to its destructive nature. Here, we find that TCP over the western North Pacific (WNP) exhibits significantly interdecadal variability and regional characteristics, a departure from the previous studies focusing on the entire WNP. The Atlantic Multidecadal Oscillation (AMO) mainly causes a dipole response of decadal changes in TCP over the South China Sea and coastal eastern China. Moreover, the AMO primarily affects TCP over the sub‐regional WNP through the extra‐tropical pathway by exciting a Rossby wave train. On the other hand, the Interdecadal Pacific Oscillation (IPO) predominantly affects TCP over the southeastern part of the WNP through the tropical pathway, inducing significant circulation anomalies over the tropical WNP. These findings offer valuable insights for future research and forecasting of TCP. Key Points: The Atlantic Multidecadal Oscillation (AMO) contributes to the dipole pattern of interdecadal tropical cyclone precipitation (TCP) anomalies over the South China Sea and coastal eastern ChinaThe AMO affects TCP by triggering a westerly jet‐guided Rossby‐wave train via the extra‐tropical pathwayThe Interdecadal Pacific Oscillation dominates the TCP anomalies over the southeastern part of western North Pacific by modulating tropical circulation anomalies [ABSTRACT FROM AUTHOR]

A prominent feature of the western North Pacific tropical cyclone genesis frequency (TCGF) anomaly in response to El Niño‐Southern Oscillation (ENSO) is a distinct west‐east dipole structure in the present‐day (PD) climate. Here, large ensemble high‐resolution simulations show that the current dipole may transform into a monopole under global warming (GW). In the PD climate, the ENSO‐induced dipole effect on TCGF is mainly observed in late autumn. However, GW accelerates this effect into the summer by amplifying atmospheric circulation anomalies. Consequently, this leads to a significant increase in the coastal TCGF during the development phase of El Niño under GW. Meanwhile, it weakens the anomalous anticyclonic circulation during late autumn, leading to an increase in coastal TCGF during the mature phase of El Niño, and vice versa. Therefore, the combined effect suggests a potential trend toward spatial homogenization during ENSO phases under GW. Plain Language Summary: El Niño‐Southern Oscillation (ENSO) typically has a dipole impact on tropical cyclone genesis frequency (TCGF) over the western North Pacific (WNP) in the current climate. During the warm phase of ENSO, there is a significant increase in TCGF over the southeastern part of the WNP (open‐sea region), but a decrease over its northwestern part (coastal region). The opposite pattern occurs during the cold phase of ENSO. However, under global warming (GW), this dipole pattern could transform into a basin‐uniform change in TCGF. In the present climate, ENSO primarily affects TCGF only over the open‐sea region during the summer (June to August) but causes a dipole pattern of TCGF anomalies in the autumn (September–November). The summer TCGF over the coastal region is less influenced by ENSO. Hence, the dipole pattern of TCGF anomalies from summer to autumn is mainly contributed by the anomaly in autumn TCGF over the coastal region. However, GW could extend the ENSO impact on coastal TCGF to summer. Therefore, the TCGF anomaly in summer offsets the opposite TCGF anomaly in autumn over the coastal region during the ENSO phase, resulting in a more consistent change in TCGF anomalies across the region under GW. Key Points: The dipole pattern of tropical cyclone genesis frequency (TCGF) during June–November in response to El Niño‐Southern Oscillation (ENSO) over the western North Pacific may transform into a monopole under global warming (GW)The present‐day dipole of TCGF anomaly is mainly observed in late‐autumn, while GW accelerates this impact to summerGW amplifies cyclonic (anticyclonic) circulation during warm (cold) ENSO phases, causing a basin‐uniform TCGF change [ABSTRACT FROM AUTHOR]

How future multiple tropical cyclone events (MTCEs) could change is crucial for effective risk management and ensuring human safety, however, it remains unclear. This study projects changes in MTCEs by 2050 in the major basins of the Northern Hemisphere using high‐resolution climate models. Results show a significant increase in the frequency and duration of MTCEs over the North Atlantic (NA), a notable decrease over the western North Pacific (WNP), and little change over the eastern North Pacific (ENP). The increase in MTCEs over the NA is concentrated in August–September, while the decrease over the WNP occurs in most months. In contrast, the ENP exhibits large yet insignificant seasonal variation, suggesting considerable uncertainty in this basin. Further analysis shows that mid‐level vertical motion dominates the MTCE changes over the WNP, while vertical wind shear contributes the most to the NA, which may be linked to future changes in tropical convection. Plain Language Summary: Multiple tropical cyclone (TC) events (MTCEs), that is two or more TCs simultaneously occurring in the same basin, pose great risks to human society. This study projects future changes in the MTCEs by 2050, showing a significant increase over the North Atlantic (NA) while a robust reduction over the western North Pacific (WNP). The future MTCEs over the eastern North Pacific (ENP) show little change relative to the present climate. The increase of MTCEs over the NA is concentrated in August–September, while the decrease over the WNP occurs nearly from April to November. In contrast, there is large yet insignificant seasonal variation over the ENP, which could lead to little change in annual MTCEs. Furthermore, these changes are primarily attributed to the changes in local large‐scale dynamic conditions associated with tropical convection in future decades. Key Points: The projection of future multiple tropical cyclone events (MTCEs) shows a decline in the western North Pacific (WNP) but a significant increase in the North Atlantic (NA)The mid‐level vertical motion dominates the MTCE changes over the WNP, while vertical wind shear is important for the NAFuture monthly MTCEs show large yet insignificant seasonal variation over the eastern North Pacific, causing little trend in annual MTCEs [ABSTRACT FROM AUTHOR]