摘要
应用合成分析、距平分析和差值分析等方法,对美国NCEP/NCAR的再分析资料和辽宁地区逐日降水资料进行分析,对比春季降水多、少月份的大气环流、影响系统、风场和温湿场特征。结果表明:降水多月,乌山脊和东亚大槽减弱,位相比历年平均偏西,中高纬大气环流纬向度增大,导致冷空气移动快,活动频繁;辽宁位于地面气压场负距平带内,地面辐合上升加强;40°N附近80°E-125°E区域的冷干平流、中低纬地区中国大陆东部20°N-38°N区域的暖湿平流均增强,辽宁位于冷干平流和暖湿平流交汇的区域。降水少月,乌山脊和东亚大槽增强,位相比历年平均偏东,中高纬大气环流经向度增大,系统稳定少动,辽宁位于脊前,对应地面反气旋控制,多晴天少雨天气;辽宁在地面气压场正距平带内,地面辐散加强;40°N附近80°E-125°E区域的冷干平流、中低纬地区中国大陆东部20°N-38°N区域的暖湿平流均减弱,冷干平流和暖湿平流交汇活动减少,导致少雨。
The daily precipitation in Liaoning Province and data from NCEP/NCAR during 1960 and 2006 were analyzed by using composite analysis, corresponding analysis and difference analysis methods. The atmospheric circulation patterns, impact systems and wind vectors field during the spring were discussed. The result showed that in the more rain months of the spring in Liaoning Province, the Wula＇er montain ridge and the East Asia trough were weaker, but their positions were partial west as usual years. The circulation appeared zonal surface converging and ascending actions became stronger, which led to a stronger west cold dry current and south warm and wet air. In the less rain months of the spring in Liaoning Province, the Wula＇er montain ridge and the East Asia trough were stronger, but their positions were partial east as usual years. The fall movement became strong, the west cold dry current and the south warm and wet air became weaker than more rain months.
出处
《中国农业气象》
CSCD
2009年第1期66-69,共4页
Chinese Journal of Agrometeorology
关键词
辽宁省
春季降水
大气环流
合成分析
距平分析
差值分析
Liaoning Province
Spring precipitation
Atmospheric circulation composite analysis
Rorresponding analysis
Difference analysis
