摘要
选用2005—2009年沈阳地区5个气象站点的气象资料,总结了沈阳地区雾天的时空分布规律。沈阳地区一年中近一半的时间出现轻雾,大雾年平均16.4天;轻雾和大雾的季节分布都呈夏、秋季多,春季少的态势;大雾多发时段在清晨。在数值预报的基础上,利用UPS预报方法,进一步做出大雾天气订正预报,建立沈阳地区大雾天气UPS订正预报方法。当数值预报有大雾时,如T-Txover(最高气温出现时段温度露点差)≤5℃则可预报有大雾,当-4℃<T-Txover≤5℃时可预报未来会出现能见度小于等于500m的浓雾;如T-Txover≤-4℃则预报未来会出现能见度小于等于200m的强浓雾。如T-Txover>5℃则有暖湿平流时预报有大雾,无暖湿平流时预报不会出现大雾。
The meteorological data from five meteorological stations in Shenyang from 2005 to 2009 are used, and the spatial and temporal distribution regularities of fogs in Shenyang are summarized. The results show that there appears mist weather in nearly half a year in Shenyang, 16.4 heavy fog days per a year averagely. The frequency of mist and fog weather is relatively high in summer and autumn, and low in spring. Heavy fogs tend to appear in the morning. On the basis of the numerical forecasting, using the UPS forecasting method to make correction forecasting further for fog weather, the fog forecasting procedure {or the Shenyang area is established. When the numerical forecast for fog weather shows T- Txover ≤45 ℃,then there will appear fog weather; if -4 ℃〈T-Txover≤ 45 ℃, there will be fog with visibility 4500 m; and if T-Txover 4-4 ℃, there will be strong fog with visibility 4200 m. When T-- Txover〉5 ℃, if there is warm and moist advection, there will be fog weather, and if there is no warm and moist advection, there will no fog weather appear.
出处
《气象科技》
2013年第5期878-882,共5页
Meteorological Science and Technology
关键词
大雾
轻雾
UPS预报方法
转换温度
heavy fog, light fog, UPS forecasting procedure, crossover temperature
