ENSO对西北太平洋台风快速增强位置影响的年代际变化及机理OA

Different El Niño-Southern Oscillation(ENSO)events exhibit pronounced diversity during their decay phases,and the rate of ENSO decay can substantially influence the locations of tropical cyclone(TC)rapid intensification(RI)over the Western North Pacific(WNP)in boreal summer.To quantitatively characterize ENSO evolution during the decay phase,this study introduces a new metric,the ENSO Changing Rate(ECR),and reveals the modulatory role of the Interdecadal Pacific Oscillation(IPO)in the relationship between ECR and RI locations.The period 1951-2024 is divided into three subperiods(P1:1951-1978,P2:1979-1998,and P3:1999-2024).The results show pronounced interdecadal variations in the correlation between ECR and the longitude of RI occurrence,which are synchronized with IPO phase transitions:a significant positive correlation is found during the negative IPO phases(P1 and P3),whereas a negative correlation emerges during the positive IPO phase(P2).By modulating the ENSO decay rate,the IPO alters the large-scale atmospheric and oceanic responses over the WNP during ENSO decay summers.During the negative IPO phases,ENSO events tend to decay rapidly,leading to more favorable atmospheric and oceanic conditions for RI over the western WNP,such that ECR effectively regulates the longitude of RI occurrence.In contrast,during the positive IPO phase,ENSO decay is slower and the large-scale environment over the WNP becomes less favorable for RI,with RI locations being more strongly influenced by TC tracks and environmental conditions along the tracks.These results provide physical insight into the interdecadal modulation of ENSO impacts on RI and offer a scientific basis for developing RI seasonal prediction models with interdecadal adaptability.