辽宁春播期首场透雨时空分布特征及天气形势分析

Temporal-Spatial Distribution Characteristics of the First Soaking Rain in Spring Soaking Season of Liaoning Province and Its Synoptic Analysis

利用1960—2014年4—5月辽宁省49个气象站逐日降水资料和NCEP再分析资料,对辽宁春播期首场透雨的时空分布特征及天气形势进行分析。结果表明:(1)单站透雨平均出现日期、无透雨次数和平均透雨量的空间分布都存在明显的地区差异,如透雨平均出现日期自东向西逐渐偏晚,辽东南部最早,辽西最晚;(2)区域性透雨近55年平均出现日期为4月19日。从周期变化来看,区域性透雨初日存在14、9、5、3年左右的变化周期。区域性透雨量空间分布最多的是在总体一致的背景下呈现自东南向西北递减的分布规律,其次是中东部与西部相反的空间分布,即中东部有(没)透雨,而西部没(有)透雨;(3)辽宁区域性透雨高空环流可分为深槽型、东亚倒Ω型和短波槽型三类天气学模型。

Based on daily precipitation data of 49 meteorological stations May during 1960-2014 and NCEP reanalysis data, the temporal-spatial synoptic conditions of the first soaking rain were analyzed during spring in Liaoning Province from April to distribution characteristics and its soaking season in Liaoning Province. The results show that evident regional differences exist in the spatial distribution of average date of single station soaking rain, the number of no soaking rain and average soaking rainfall, such as average dates of single station soaking rain are gradually late from east to west. The average date of regional soaking rain is April 19 in recent 55 years, and there are periodic variations about 14, 9, 5 and 3 years. The most spatial distribution pattern of regional soaking rainfall is that the rainfall distribution decreases gradually from southeast to northwest under the bac and east region are contrary to which kground of the overall consensus, the spatial distribution which in middle in the west is secondly, that is to say, there are soaking rain in middle and east, but not in west, and vice-versa. Upper air circulation of regional soaking rain can be divided into three kinds of synoptic models： deep trough pattern, east Asia inverted Ω pattern and short wave trough pattern.