京津冀冬季极端污染事件的时空特征及类环球遥相关异常环流的影响  

Spatial-Temporal Characteristics of Winter Extreme Pollution Events in Beijing-Tianjin-Hebei Region and the Effects of Quasi-Circumglobal Teleconnection Anomalous Circulation

作　　者：孙佳铭 黄菲[1] 

机构地区：[1]中国海洋大学深海多圈层与地球系统前沿科学中心和物理海洋教育部重点实验室,山东 青岛

出　　处：《气候变化研究快报》2024年第4期1022-1032,共11页Climate Change Research Letters

摘　　要：随着近几十年来全球变暖加剧,北极海冰加速融化,异常的大气环流场造成京津冀极端污染天气频发。本文基于京津冀地区PM2.5浓度大于95%极端事件阈值(162.5 μg/m3)筛选的极端污染事件,分析了2000~2022年冬季京津冀地区极端污染事件的时空分布特征。结果表明,近23年冬季共发生了135个极端污染日。污染主要发生在京津冀东南部和中部,空间上呈东高西低的分布;极端污染事件发生频次在2014年之后呈现出显著的年代际减少特征,2019年后没有极端污染事件发生。极端污染事件平均持续2.3天,最长为10天,主要发生在1月,12月和2月发生的次数较少。在极端污染高发年,西伯利亚高压减弱,东北亚异常反气旋加强,盛行西风减弱,逆温增强,污染扩散条件差,有利于极端污染发生;该东北亚异常反气旋主要受上游源自北大西洋的类环球遥相关波列所影响。With global warming in recent decades, the melting of Arctic Sea ice has been accelerated, results in abnormal atmospheric circulation which has caused frequent extreme pollution weather in Beijing-Tianjin-Hebei (BTH) region. In this paper, spatial and temporal characteristics of extreme pollution events in BTH from 2000 to 2022 are studied. Extreme pollution events are selected based on the 95% PM2.5 concentration threshold (162.5 μg/m3) in BTH. The results show that a total of 135 extreme pollution days occurred in DJF (December, January and February) of the past 23 years. The pollution mainly occurs in the southeast and central BTH, and it is high in the east and low in the west. The frequency of extreme pollution events shows a significant interdecadal decrease after 2014, and no extreme pollution events happens after 2019. The average duration of extreme pollution events is 2.3 days with a maximum of 10 days. Extreme pollution events mainly occur in January, with fewer occurrences in December and February. In high pollution years, the Siberian high weakens, the anomalous anticyclone is established in Northeast Asia, the prevailing westerly wind weakens, the temperature inversion increases, result in poor pollution diffusion conditions, which are benefit to form extreme pollution. The Northeast Asian anomaly anticyclone is influenced by a quasi-circumglobal teleconnection originated from the North Atlantic.

关 键 词：京津冀 极端污染事件 东北亚异常反气旋 类环球遥相关波列 

分 类 号：F12[经济管理—世界经济]