Atmospheric circulation characteristics and impacts of sea surface temperature on abnormal precipitation in Shanxi during midsummer 2022

Under global warming, understanding climate anomalies and their drivers remains essential for improving short-term climate forecasting and regional disaster mitigation. This study analyzes circulation characteristics and sea surface temperature (SST) influences on abnormal midsummer precipitation in Shanxi during 2022 using observational data from 108 meteorological stations in Shanxi, NCEP/NCAR reanalysis, NOAA SST datasets, and 130 climate indices from China's National Climate Center from 1980 to 2022. Results show that: (1) Area-averaged precipitation reaches 320 mm, exceeding the 1991-2020 climatological mean by 49% and ranking as the second highest since 1980, with localized areas receiving over twice normal amounts. Spatially, precipitation anomalies exhibit dominance of the EOF1 mode alongside EOF2 features. (2) Intensified Ural and Okhotsk blocking highs, combined with an anomalously active Baikal trough and an unusually westward and northward displaced western Pacific subtropical high (WPSH), cause convergence between descending mid-high-latitude cold air and warm moist airflow from the WPSH periphery over Shanxi. Sufficient dynamic forcing and moisture supply directly result in abnormally heavy precipitation in