大气科学2026，Vol.50Issue(1)：81-95,15.DOI:10.3878/j.issn.1006-9895.2410.24069
2021年秋季我国北方极端降水的可能成因分析
Analysis of the Potential Causes of Extreme Precipitation in Northern China during the Autumn of 2021
摘要
Abstract
The increased extreme precipitation in recent years has significantly affected human life and caused urban flooding.Therefore,forecasting extreme precipitation and identifying its precursor factors are of great importance.In this study,we analyze the spatiotemporal characteristics of the extreme precipitation event that occurred in northern China during September-October 2021,and examine the associated circulation background and influencing factors.Results show that the accumulated extreme precipitation exceeds 220 mm,making this event the strongest autumn extreme precipitation since 1961.Autumn precipitation in China is mainly affected by the ENSO(El Niño-Southern Oscillation).During this period,a developing La Niña phase induced an anomalous anticyclone that enhanced water vapor transport.However,the influence of ENSO was mainly confined to regions south of 39°N,whereas extreme precipitation north of 39°N was primarily associated with the anomalous activity of the MJO(Madden-Julian Oscillation).The MJO was anomalously active in phases 3-5,with an intensity 2-3 times its climatological mean.This enhanced intraseasonal-scale upward motion promoted water vapor convergence,resulting in the occurrence of extreme precipitation.Statistical analyses further show that the probability of extreme precipitation in northern China increases by more than 60％when the MJO is active in phase 4.These findings provide valuable insights for improving the forecasting and early warning of extreme precipitation events in northern China.关键词
极端降水/ENSO/MJOKey words
Extreme precipitation/ENSO/MJO分类
天文与地球科学引用本文复制引用
谢爽,祁莉,王子佳..2021年秋季我国北方极端降水的可能成因分析[J].大气科学,2026,50(1):81-95,15.基金项目
国家重点研发计划项目2022YFF0801602 Funded by National Key Research and Development Program on Monitoring(Grant 2022YFF0801602) （Grant 2022YFF0801602）
