基于FLEXPART模式对黄河源区盛夏降水异常的水汽源地及输送特征研究  

The Characteristics of the Water Vapor Transport and Associated Sources under Abnormal Precipitation Conditions in the Source Region of the Yellow River Using FLEXPART

作　　者：朱丽 刘蓉 王欣 王作亮 文军 赵阳[4] 谢琰 张堂堂 ZHU Li;LIU Rong;WANG Xin;WANG Zuoliang;WEN Jun;ZHAO Yang;XIE Yan;ZHANG Tangtang(Key Laboratory of Land Surface Process and Climate Change in Cold and Arid Regions,Northwest Institute of Ecology and Environmental Resources,Chinese Academy of Sciences,Lanzhou 730000,Gansu,China;University of Chinese Academy of Sciences,Beijing 100000,China;School of Atmospheric Sciences,Chengdu University of Information Technology,Chengdu 610000,Sichuan,China;Chinese Academy of Meteorology Sciences,Beijing 100000,China)

机构地区：[1]中国科学院西北生态环境资源研究院/中国科学院寒旱区陆面过程与气候变化重点实验室,甘肃兰州730000 [2]中国科学院大学,北京100049 [3]成都信息工程大学大气科学学院/高原大气与环境四川省重点实验室,四川成都610225 [4]中国气象科学研究院,北京100000

出　　处：《高原气象》2019年第3期484-496,共13页Plateau Meteorology

基　　金：国家自然科学基金项目(41530529,91737103)

摘　　要：依据近10年黄河源区流域气象台站的降水观测资料,提取夏季降水最强月对应的异常特征,利用拉格朗日粒子扩散模式(Flexible Particle Dispersion Model,FLEXPART),针对目标时段开展大气粒子群(气块)的后向模拟,着重分析了流域内降水正负异常状态下的水汽输送特征及其差异,并评估各水汽源地对流域内三类降水的贡献。结果表明,以“S”型跨赤道输送(“由阿拉伯海至孟加拉湾和印度半岛再由青藏高原西南侧进入黄河源区”)和“几”型输送(“由南中国海经长江中下游平原后途径四川盆地再进入黄河源区”)为代表的南支路径是2012年7月黄河源区对应的主要水汽输送路径;而以东、西风急流作用下的两条远距离输送(“由南中国海至孟加拉湾和印度半岛东北部附近后再经由青藏高原西侧或北侧进入黄河源区”以及“由欧洲平原东部和中亚地区进入青藏高原西侧或北侧后到达黄河源区”)为代表的北支路径是2015年7月黄河源区对应的主要水汽输送路径。在对气块后向模拟追踪的同时,对其运动过程中的比湿变化进行了对应经纬度网格的空间平均,变化特征显示出喜马拉雅山南麓、四川盆地周边、孟加拉湾和青藏高原北侧是黄河源区流域降水对应的潜在水汽源地。由定量评估贡献率的结果可知:青藏高原北侧的广大干旱及半干旱草原地区是2015年7月黄河源区降水的最主要水汽来源,其贡献率高达52.9%;而在2012年,三个主要源地的贡献率差异远不及2015年显著;无论对应何种类型的降水,青藏高原西南部和北侧提供了黄河源区主要可供降水的外来水汽。Based on the precipitation observation data of meteorological stations in the source region of the Yellow River (SRYR) in the past ten years, July is selected as the largest month of precipitation, the maximum positive and negative abnormal year's corresponding to July are 2012 and 2015 respectively. The Lagrange Flexible Particle Dispersion Model (FLEXPART) is driven by NECP reanalysis data to simulate the backward trajectories of target particles in these two months. The characteristics and differences of water vapor transport under abnormal conditions are emphatically analyzed, and the contribution rate of each moisture source to the regional rainfall is calculated quantitatively. The results show that, in July 2012, the moisture transportation to the SRYR is mainly conducted by South Branch which contains two routes entering the SRYR from the southern side of the Qinghai-Tibetan Plateau (QTP):one is the trans-equatorial transport path, that is to say, the Somali jet carries moisture from the Arabian Sea and finally enters the SRYR by way of the Indian Peninsula and Bay of Bengal;the other is that particles carry moisture from the South China Sea and finally enters the SRYR by way of the Sichuan Basin. On the contrary, the North Branch which means moisture enters the SRYR from the Western or northern side of the QTP plays a dominant role in July 2015, including two typical paths as well:one is that the Easterly jet carries the moisture from the South China Sea and finally enters the SRYR by the Bay of Bengal and Indian Peninsula;the other is that the Westerly Jet carries moisture from the northern Africa or eastern European Plain and finally enters the SRYR, via Central Asia. The characteristics of specific humidity variation during the movement of particles show that the southern foot of the Himalayas, the Sichuan Basin, the Bay of Bengal and the northern Tibetan Plateau are potential moisture sources for precipitation in the SRYR. Moreover, the estimation of moisture sources contributions to the precipitatio

关 键 词：黄河源区 降水异常 拉格朗日方法 后向追踪 水汽输 

分 类 号：P426[天文地球—大气科学及气象学]