石家庄暴雪天气过程中相态转变的温度指标分析  

Study on the Temperature Index of Precipitation Phase Change in the Snowstorm Weather Process in Shijiazhuang

作　　者：阎访[1] 孙婧怡 Yan Fang;Sun Jingyi(Shijiazhuang Meteorological Bureau,Shijiazhuang 050081,China;School of Atmospheric Science,Chengdu University of Information Technology,Chengdu 610225,China)

机构地区：[1]石家庄市气象局,河北石家庄050081 [2]成都信息工程大学大气科学学院,四川成都610225

出　　处：《气象与减灾研究》2020年第2期106-116,共11页Meteorology and Disaster Reduction Research

基　　金：河北省气象局科研开发项目(编号:18ky21).

摘　　要：利用1999—2017年石家庄国家基本气象观测站的降水实况资料,统计出暴雪天气过程,在分析其地面和高空影响系统的基础上,着重分析暴雪天气过程中温度场的变化特征。结果表明:暴雪天气过程的地面影响系统为冷高压和低压倒槽共存的形势,但高空系统存在差异;没有相态转变而以固态雪的形式出现的暴雪天气过程中,对流层中没有逆温层,整个对流层温度小于0℃,且700 hPa高度以下的中低空温度小于-5℃;有相态转变的暴雪天气过程中,925—700 hPa多存在逆温层,其存在有利于降水的维持和发展,850 hPa和925 hPa可视为特性层,850 hPa温度小于-4℃,925 hPa温度小于等于-2℃,0℃层的高度位于950 hPa以下,可作为预报雨或雨夹雪转雪的参考指标;地面气温大于0℃且小于1℃可视为过渡相态雨夹雪的地面气温临界值。Using the precipitation data of Shijiazhuang ground meteorological observation station from 1999 to 2017,the variation characteristics of temperature field during snowstorm processes were discussed based on the analysis of its ground and higher level weather situations.The results showed that:the cold-high pressure and low pressure-inverted trough coexisted in the ground were the impact systems of snowstorm weather processes,however,there presented differences in higher level weather system;When the solid snow occurred without phase change,no inversion layer existed in the troposphere and the temperature was less than 0℃in the troposphere,and the temperature of middle-low layer below 700 hPa altitude was less than-5℃;During the precipitation phase-changing weather processes,the inversion layer always existed between 925-700 hPa height,which was beneficial to the maintenance and development of precipitation.Temperature under 850 hPa and 925 hPa was below-4℃and-2℃,respectively,and the height of 0℃layer was lower than 950 hPa can be considered as a temperature reference index to predict rain or sleet changing to snow.The ground temperature of 0-1℃can be regarded as the threshold of the sleet with phase transition.

关 键 词：暴雪 降水相态 温度指标 天气形势 石家庄 

分 类 号：P457.6[天文地球—大气科学及气象学]