大气科学2025，Vol.49Issue(6)：1649-1662,14.DOI:10.3878/j.issn.1006-9895.2510.25147
2024年11月西北太平洋极端多台风生成的多尺度驱动研究
Multiscale Driving Mechanisms of the Genesis of Rare Extreme Multityphoons over the Northwestern Pacific Ocean in November 2024—Based on the Dynamic Genesis Potential Index Decomposition
摘要
Abstract
In November 2024,a rare extreme phenomenon of four typhoons coexisting simultaneously occurred over the northwestern Pacific Ocean.As the typhoon tracks approached China's coastal areas,many regions experienced strong gusts and were threatened by persistent heavy rainfall.To unravel its formation mechanism,this study systematically investigates the external forcing factors driving this rare extreme phenomenon and the characteristics of large-scale circulation anomalies induced by these factors using the best-track typhoon dataset of the China Meteorological Administration and National Centers for Environmental Prediction/National Center for Atmospheric Research(NCEP/NCAR)atmospheric reanalysis data.Results show that the synergistic effect between the sustained accumulation of upper-ocean heat on seasonal-to-interannual scales and the subseasonal signals of the Madden-Julian Oscillation(MJO)was the main mechanism responsible for this extreme phenomenon.On the one hand,throughout 2024,the upper-ocean temperature over the western Pacific was abnormally high,and the Pacific Meridional Mode was in a positive phase.These two factors led to a stronger intensity and a westward-northward shift of the western Pacific subtropical high as well as an intensified Australian high.This anomaly pattern further induced strong cross-equatorial flows,transporting abundant moisture and convergent air currents.On the other hand,a quantitative diagnosis based on the Dynamic Genesis Potential Index(DGPI)indicates that the contribution of the vertical motion term(55.0%)was considerably higher than that of wind shear(27.3%)and absolute vorticity(24.7%),making it the core dynamic factor dominating the genesis of these rare extreme multityphoons.Further analysis indicated that this anomalous ascent was primarily driven by the active MJO on the subseasonal scale.MJO-induced Kelvin waves and their associated circulation anomalies unusually maintained and extended the monsoon trough eastward,providing a large-scale,persistent background of cyclonic shear and deep convection conducive to typhoon genesis,ultimately leading to the rare extreme phenomenon of four concurrent typhoons of"four typhoons coexisting".关键词
极端多台风/动力潜在生成指数(DGPI)分解/台风生成机制/多尺度协同Key words
Extremely frequent typhoons/Dynamic Genesis Potential Index(DGPI)decomposition/Typhoon generation mechanism/Multi-scale collaboration分类
天文与地球科学引用本文复制引用
郑飞,邓星辰,陈光华,赵伟..2024年11月西北太平洋极端多台风生成的多尺度驱动研究[J].大气科学,2025,49(6):1649-1662,14.基金项目
国家自然科学基金项目42430114,海南省市县联合专项项目 ZDYF2025SXLH011 National Natural Science Foundation of China(Grant 42430114)and the Key R&D Program of Hainan Province(Municipality-County Joint)Project(Grant ZDYF2025SXLH011) （Grant 42430114）
