全球气候系统变化导致华北雨季超长“待机”

Core Insights - The article discusses the unusually long and wet rainy season in North China, which began on July 5, 2023, 13 days earlier than the average start date of July 18, marking the earliest onset since 1961 [1][2] - The average rainfall in the North China monitoring area reached 315.5 mm, which is 131% higher than the normal value of 136.6 mm [2] - The record-breaking rainfall is attributed to multiple factors, including abnormal sea temperatures in the equatorial Pacific, a strong and shifted subtropical high-pressure system, typhoon activity, and geographical influences [3][4] Summary by Sections Rainy Season Characteristics - The rainy season in North China has lasted for 52 days as of August 25, significantly longer than the typical duration of 30 days [1] - The rainy season is characterized by increased rainfall frequency, volume, and humidity, contributing to a notably damp environment [2] Factors Contributing to Abnormal Weather - The subtropical high-pressure system has been stronger and positioned further north than usual, facilitating the transport of warm, moist air from lower latitudes to northern China [3] - Historical data indicates that the combination of typhoons and the subtropical high can lead to extreme rainfall events, as seen with Typhoon "Kanu" and Typhoon "Zhu Jie Cao" [3] Climate Change Implications - The record rainfall in North China is viewed as a local manifestation of global climate system changes, emphasizing the need for improved climate adaptation and response capabilities to address extreme weather challenges [4]