Relationship Between Summer Flood and Drought in Shaanxi Province and Eurasian Atmospheric Circulation Anomalies
Shaanxi is located at the edge of the Qinghai-Tibet Plateau,with a narrow and elongated shape,diverse climate types,complex topography and fragile ecological conditions.Drought and flood are the main meteorological disasters in summer,so analyzing the causes of drought and flood in this area is of great significance for disaster prevention and reduction.Based on the precipitation data of 78 meteorological stations in Shaanxi from 1961 to 2018,NCEP/NCAR height and wind fields reanalysis data,and the subtropical Western Pacific Index data,this paper studies the relationship between the abnormalatmospheric circulation and the drought and flood in summer in Shaanxi through correlation,synthesis,and multiple regression analysis.The results show that the blocking high over the Ural Mountains and the subtropical Western Pacific are the key factors affecting the drought and flood in sum-mer in Shaanxi.When the blocking high over the Ural Mountains and the subtropical Western Pacific are strong,the precipitation during summer in Shaanxi is abundant,while it is scarce otherwise.The position of the westerly jet at 200 hPa is closely related to the precipitation in summer in Shaanxi.When the jet is located to the south,the precipitation in summer in Shaanxi is abundant,while it is scarce otherwise.When the subtropical high in the Western Pacific is strong and located to the west,the precipitation in summer in Shaanxi is abundant,while it is scarce otherwise.The location of the subtropical high frontal mainly affects the north-south movement of the rain band in summer in Shaanxi.
Shaanxi summer flood and droughtEurasian atmospheric circulation anomaliesWestern Pacific subtropical high indexesUral blocking high200 hPa westerly jet stream
NETL
NSTL
万方数据
