气象2016，Vol.42Issue(11)：1342-1350,9.DOI:10.7519/j.issn.1000-0526.2016.11.006
西藏夏季降水的季节内变化特征及其影响系统
Intraseasonal Variation Characteristics of Summer Precipitation over Tibet and the Corresponding Large-Scale Circulation Anomalies
摘要
Abstract
Based on the summer precipitation data over Tibet and monthly NCEP/NCAR reanalysis data during the period from 1980 to 2013,we analyzed the intraseasonal variation of summer precipitation prin-cipal mode,especially the large-scale circulation features of corresponding precipitation anomalies in July and August.The results show that obvious intraseasonal variation exists in summer rainfall over Tibet. The correlation coefficient of PC1 between June and July principal mode is significant while weak between July and August.In more-rain years,the upstream zonal wind of the Tibetan Plateau is westerly anomaly in July and August but the moisture water vapours come from different regions.And the upper tropo-sphere circulation in the mid-high latitude over Eurasia in July and August is different significantly.Fur-ther research shows a strong negative correlation between precipitation and the intensity of South Asian high (SAH)in July,which means more-rain/less-rain in July,SAH is weaker/stronger.In August,there is a strong correlation between precipitation and the position of SAH.That is,SAH southward/northward to its normal position may lead to flood/drought over Tibet in August.关键词
西藏/夏季降水/季节内变化/南亚高压Key words
Tibet/precipitation in summer/intraseasonal variation/South Asian high分类
天文与地球科学引用本文复制引用
次仁央宗,柯宗建,陈丽娟,尼玛吉..西藏夏季降水的季节内变化特征及其影响系统[J].气象,2016,42(11):1342-1350,9.基金项目
公益性行业（气象）科研专项（GYHY201306024）、国家重点基础研究发展计划（973计划）（2015CB453203和2013CB430203）及国家自然科学基金项目（41275073、41005051和41405070）共同资助 （）
