李秀珍,唐旭紫,李施华,温之平. 2018. 春季青藏高原感热对中国东部夏季降水的影响和预测作用[J]. 气象学报, (0):-, doi:10.11676/qxxb2018.061
春季青藏高原感热对中国东部夏季降水的影响和预测作用
Impact of the spring sensible heat flux over the Tibetan Plateau on the summer rainfall over East China and its role in the rainfall prediction
投稿时间:2018-03-11  修订日期:2018-09-18
DOI:10.11676/qxxb2018.061
中文关键词:  感热通量,青藏高原,中国夏季降水,预报技巧
英文关键词:Sensible heat flux, Tibetan Plateau, Rainfall over East China, Prediction skill
基金项目:国家重点基础研究规划项目,国家自然科学基金
作者单位E-mail
李秀珍 中山大学 greenxiuzhen@163.com 
唐旭紫 中山大学 tangxuzi@mail2.sysu.edu.cn 
李施华 中山大学 lishh2017@qq.com 
温之平 复旦大学 eeswzp@mail.sysu.edu.cn 
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中文摘要:
      本文利用1980-2012年高原中-东部71个站点观测资料、全国756站的月降水资料、Hadley中心提供的HadISST V1.1海温资料以及ERA-Interim再分析资料,综合高原的感热加热以及全球海温,研究了春季青藏高原感热对中国东部夏季降水的影响,并建立预报方程,探讨了青藏高原春季感热对中国降水的预报作用。结果表明,青藏高原春季感热与中国东部降水关系密切,高原春季感热异常增加伴随着长江流域中下游同期降水偏多,后期夏季长江流域整流域降水也持续偏多,华南东部降水偏少。春季高原感热的增强与环北半球中高纬的波列密切相关,扰动在北太平洋形成的反气旋环流往西南方向延伸至西北太平洋,为长江流域输送大量的水汽,有利于降水的发生。在夏季,伴随着前期高原感热的增强,南亚高压位置偏东,西太平洋副热带高压位置偏西偏南,副高北侧为气旋式环流异常。在副高的控制下,华南东部降水减少;副高西侧的偏南气流为长江流域带来大量水汽,并与来自北部的偏北风异常发生辐合,降水增多。 高原春季感热异常是华南和长江流域夏季降水异常的重要前兆信号。加入高原春季感热后,利用海温预报的华南、长江流域夏季降水量与观测值的相关系数有所提高,预报方程对区域降水的解释方差提高约15%。
英文摘要:
      By using observational data at 71 stations over the central and eastern Tibetan Plateau, monthly rainfall data from 756 rain gauges throughout China, HadISST V1.1 and ERA-Interim reanalysis data, the impacts of the spring sensible heat flux over Tibetan Plateau along with the global SST on the rainfall over East China were investigated. Aim of this study is to improve the prediction skill of summer rainfall over China by using the sensible heat observation over Tibetan Plateau in the previous spring. Results show that there is a close relationship between the spring sensible heat flux over Tibetan Plateau and the rainfall over East China. When the upward sensible heat flux over Tibetan Plateau is increased in spring, the rainfall is increased over the middle and lower Yangtze River valley in spring and throughout Yangtze River valley in the following summer with the rainfall over eastern Southeast China decreased. The increase of the sensible heat flux over Tibetan Plateau concurs with a Rossby wave train along the middle-high latitude of the northern hemisphere. The anticyclone robe over North Pacific extends southwestward to the western North Pacific and transport abundant moisture to the Yangtze River valley. In the following summer, the South Asian high shifts eastward and the western Pacific subtropical high shifts westward in the lower and middle troposphere with a cyclonic anomaly to the north. Under the control of the subtropical high, the rainfall over Southeast China is inhibited, in contrast, the rainfall over the Yangtze River valley is increased as abundant moisture is transported by the southerly flow to the west of the subtropical high, and is converged with the northerly flow advected by the cyclonic anomaly. The sensible heat flux over Tibetan Plateau in spring could act as a key precursor of the summer rainfall over Southeast China and the Yangtze River valley. With its impact considered, the predicted rainfall shows a higher consistency with the observation, and the prediction skill of the summer rainfall increases by nearly 15%.
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