2016年11月河南省一次暴雪过程成因分析

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Cause Analysis of a Snowstorm in Henan Province in November 2016

ZHANG Jianbin1YIN Meng²XU Jinxing1

（1.School of Atmospheric Physics，Nanjing University of Information Science& Technology，Nanjing

210044， China; 2.State Grid Henan Electric Power Company Kaifeng Power Supply Company， Kaifeng ， China）

Abstract：[Purposes] This study aims to investigate the meteorological causes of the snowstorm event that occurred in Henan Province on November 22，2O16，and to enhance the capacity and service level for responding to disastrous weather events.[Methods] Using conventional meteorological observation data along with NCEP and ERA5 reanalysis data，diagnostic analyses were conducted on physical quantities such as moisture，dynamic，and thermodynamic conditions during the snowstorm process.Spatial differences in phase transition conditions were also compared.[Findings] The results indicate that the main influencing systems were the upper-level trough，mid- to low-level shear line，and jet stream.The 500 hPa cold vortex center moved eastward and southward，while the southern branch trough moved slowly eastward.A southwest jet stream with wind speeds of 12m/s south of the 7OO hPa shear line provided abundant moisture，and a deep cold layer was present below 850hPa ，representing a typical snowfall weather pattern in Henan Province.A deep moisture convergence zone was observed over the snowstorm center， distributed between 700-550hPa ， with a strong moisture flux convergence center reaching -16× 10-9g/（cm2⋅hPa⋅s） .This corresponded well with an area showing precipitable water values of 16mm ，indicating sufficient moisture supply.The strong upward motion，driven by mid- to low-level convergence and upper-level divergence，served as the dynamic mechanism，with the maximum upward motion center reaching -0.8Pa/s. Cold advection in the lower layers and warm advection in the upper layers，combined with variations in atmospheric stratification from north to south，resulted inspatial differences in precipitation phase and the timing of the rain-to-snow transition.[Conclusions]The findings of this study can provide valuable reference for forecasting heavy snowfall events in Henan Province.

Keywords：snowstorm; moisture;dynamics; stratification characteristics

0 引言

暴雪是冬季主要的灾害性天气之一，常伴随着寒潮、大风、低温等天气，严重影响工农业生产和交通运输，给国民经济和人民财产造成巨大损失。（剩余4596字）