Establishment of Conceptual Schemas of Surface Synoptic Meteorological Situations Affecting Fine Particulate Pollution Across Eastern China in the Winter. Issue 23 (25th November 2020)

• Record Type: Journal Article
• Authors: Hou, Xuewei; Zhu, Bin; Kumar, Kanike Raghavendra; de Leeuw, Gerrit; Lu, Wen; Huang, Qian; Zhu, Xiaoxin
• Is Part Of: Journal of geophysical research. Volume 125:Issue 23(2020)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2020-11-25
• Subjects: meteorological variables -- synoptic weather circulations -- conceptual weather models -- China; Atmospheric physics -- Periodicals; Geophysics -- Periodicals; 551.5
• DOI: 10.1029/2020JD033153
• Languages: English
• ISSNs: 2169-897X

Abstract

Abstract: In the present study, the characteristics of weather conditions and local meteorological variables over the Beijing‐Tianjin‐Hebei (BTH) and the Yangtze River Delta (YRD) regions in the winter are analyzed using the principal component analysis (PCA) method and daily PM2.5 accumulation rate. Typical synoptic weather patterns over China in the winter can be classified into four types. During the Type 1 synoptic weather pattern, China is under the influence of the Siberian High, and northerly winds prevail; this situation is beneficial to the transport of pollutants from north to south. However, when the Siberian High is weak, southerly winds prevail which may result in the transport of pollutants from south to north. The Type 2 weather pattern refers to a weak high pressure located in the BTH resulting in the accumulation of pollutants. During the Type 3 weather pattern, an intense cold Siberian High moves to the south and affects the northern areas of China. The associated front brings heavy precipitation in the YRD resulting in the wet deposition of pollution. During the Type 4 weather condition, the weak Siberian High is blocked by the northeast cold vortex and moves towards the south, causing the accumulation of pollution in the YRD. The PCA model shows that there are two transport pathways for pollutants to the BTH (YRD) area: one from the YRD (BTH) and Shandong during Types 1 and 2 (Types 1 and 3) situations and the other one from the central provinces during Type 4 (Types 1 and 4). Key Points: The conceptual weather models for the accumulation and dissipation processes of fine particulate pollution are determined over East China The Siberian High winds reach China where the northerly winds prevailed with the transport of pollutants from north to south The weak Siberian High is blocked by the northeast cold vortex and moves towards the south and causes the accumulation of pollution