【摘要】 利用2008年1月欧亚地区500 hPa平均位势高度距平场、1月中下旬500 hPa平均位势高度场、1月气候监测资料及本市1961-2008年1月气候要素资料,采用气候统计和天气学方法,对2008年1月濮阳市出现的低温阴雪天气成因进行了分析,结果表明:濮阳市2008年1月出现持续低温阴雪天气的主要原因是与大气环流异常和"拉尼娜"事件两方面的大气候背景有关。1月中下旬大气环流稳定少动,西南暖湿气流与北方不断南下的冷空气在黄河及以南地区多次交汇,是濮阳市出现持续低温、阴雪天气的根本原因。在中高纬度欧亚地区大气环流经向度加大和副热带高压异常偏北的环流背景下,濮阳市1月易出现气温偏低、降雪偏多的天气。乌拉尔山有阻塞高压存在,在贝加尔湖两侧(50-60°N之间)有东西向横槽形成,冷空气活动频繁且势力较强,是濮阳市冬季出现低温阴雪天气的主要环流形势。在"拉尼娜"事件负距平峰值出现时间最临近年的冬季,1月濮阳市出现低温多雪的气候概率较大。更多还原

【Abstract】 According to 500 hPa Eurasia average geopotential height departure field in January 2008,500hPa average geopotential height field in mid-late January,climate monitoring data in January and climatic element data in Puyang in January from 1961 to 2008,the causes of cold snowy weather in Puyang in January 2008 were analyzed by climatic statistics and synoptic methods.The results show such a cold snowy weather has something to do with anomalous atmospheric circulation and La Nina.The stable atmospheric circulation in mid-late January,many times convergences of southwest warm-wet air stream and cold air from the north in and to the south of Yellow River basin are the two root causes of such weather.When the degree of radial direction of atmospheric circulation increases and subtropical high deviates north exceptionally,the cold snowy weather appears easily in Puyang in January.There is a blocking high pressure in the Urals and an east-west transversal trough formed at two sides of Lake Baikal area,so cold air is frequent and strong and those are main atmospheric circulation in Puyang in the winter of 2008.The probability of cold snowy weather is higher in Puyang in January in the winter which La Nina’s negative anomaly peak value appears closely.更多还原