玛曲地区夏季强降水的环流分型及水汽轨迹分析  

Analysis on Circulation Pattern and Water Vapor Source of Heavy Precipitation in Maqu Region

作　　者：李江萍[1] 杜亮亮[1] 张宇[1] 王嘉媛[1] 王劲松[2] 王式功[1] 

机构地区：[1]兰州大学大气科学学院/甘肃省干旱气候变化与减灾重点实验室,甘肃兰州730000 [2]中国气象局兰州干旱气象研究所,甘肃兰州730020

出　　处：《高原气象》2012年第6期1582-1590,共9页Plateau Meteorology

基　　金：国家科技支撑计划项目(2009BAC53B02);高等学校科技创新工程重大项目培育资金项目共同资助

摘　　要：利用青藏高原(下称高原)东北边坡玛曲地区1967—2008年12个常规气象观测站的降水资料和NCEP/NCAR再分析资料,在环流分型的基础上,应用后向轨迹模型分析了不同等级降水的不同环流型的水汽输送轨迹。结果表明:(1)暴雨发生的环流型以高原低槽型为主,大雨的发生以切变型为主。(2)暴雨的不同环流型的水汽输送轨迹差异较大,同一型暴雨不同等压面水汽轨迹较一致;大雨的不同环流型之间水汽轨迹无明显差异,同一型大雨不同等压面的水汽轨迹差异很大。(3)通过追踪不同时间长度的水汽输送的后向轨迹发现,可以用向前追踪360h的水汽输送轨迹代表玛曲地区的水汽输送,水汽轨迹以偏南气流为主。由此可见,虽然不同等级、不同环流型强降水之间的水汽轨迹存在差异,但是玛曲地区强降水的水汽主要来自印度洋-孟加拉湾和南海-孟加拉湾的偏南气流。Maqu is located in Gansu Province,lying in the northeast of the Qinghai-Xizang Plateau.It is not only the water resource of upstream and source of the Yellow River,but also the intersection of the Qinghai-Xizang Plateau and Loess Plateau,so it is very sensitive to climate change.The researches on source of water in this region were focused on different seasons and dry/wet years.However,it is limited in the study of water source in different circulation patterns.500hPa circulation pattern of heavy rain in Maqu region are analyzed using NCEP/NCAR and observation precipitation data from 1967to 2008;theHYSPLIT model is used to study the vapor track in this region.The results indicate that：（1）The main circulation pattern of causing heavy rain is pressure trough on the Qinghai-Xizang Plateau,and that causing heavy rain is shear pattern;（2）The differences of the vapor tracks of different circulation patterns for rainstorm in Maqu region are obviously distinct,while that of the vapor tracks in one circulation pattern are not distinct in three pressure levels;the differences of the vapor tracks of different circulation patterns for rainstorm in Maqu region are not distinct,while that of the vapor tracks in one circulation pattern are obviously distinct in three pressure levels;（3）The vapor transport in Maqu is found to can be represented by the vapor transport track that forward 360htracing,the vapor track was dominated by southerly airstream.In conclusion,although the vapor tracks are different in circulation patterns and precipitation amount,the moisture affecting northeast of the Qinghai-Xizang Plateau comes from Indian Ocean-the Bay of Bengal and South China Sea-the Bay of Bengal.

关 键 词：玛曲强降水 环流分型 水汽输送轨迹 HYSPLIT轨迹模式 

分 类 号：P434.5[天文地球—大气科学及气象学]