【作者】 杨莲梅； 张云惠； 汤浩；

【Author】 Yang Lianmei1) Zhang Yunhui2) Tang Hao2) 1)(Institute of Desert Meteorology,China Meteorological Administration,Urumqi,830002)(Xinjiang Meteorology Observation,Urumqi,830002)

【机构】 中国气象局乌鲁木齐沙漠气象研究所； 新疆气象台；

【摘要】 应用NECP/NCAR一日四次1o×1o再分析资料分析了2007年7月8-11日、15-17日和27-29日新疆三次暴雨过程的水汽输送和收支特征。雨型1(7月8-11日)雨带位于天山山区及其北麓,雨型2(15-17日)雨带位于新疆东部地区,雨型3(27-29日)雨带位于天山以北的北疆地区。结果表明这三种典型雨型的水汽输送路径有明显差异,雨型1存在西风气流、河西走廊至新疆的低空偏东急流(LLEJ)和青藏高原向北气流三支水汽输送路径,西方路径水汽输送量最大,这3支水汽输送在天山山区及其北麓强辐合引发暴雨,这是由700hPa贝加尔湖脊发展、对流层中亚低涡(MAV)强烈发展快速东移和500hPa新疆脊逐渐东移配置所造成的;雨型2水汽输送为西方、东方、南方和北方路径,四支水汽在东—西和南—北向强辐合引发暴雨,这种异常的水汽输送是由700hPa柴达木低压发展、500hPa乌拉尔脊东北向发展、中亚低涡东南移动和新疆脊配置所致;雨型3主要为西风气流和贝加尔湖至新疆的LLEJ输送水汽,东、西方水汽在天山以北区域发生强辐合造成暴雨,偏东水汽输送来自于贝加尔湖、孟加拉湾、南海和热带西太平洋,其水汽输送量大于西方路径,这种异常水汽输送是由MAV的东移、西太平洋副热带高压(WPSH)北伸与贝加尔湖脊叠加且贝加尔湖脊西伸配置所造成的。更多还原

【Abstract】 This paper attempts to reveal the atmospheric water vapor transports associated with three heavy rainfall processes in Xinjiang in July 2007.The results show that pathways of water vapor transport related to heavy rainfall patterns are very different.Pattern 1,with heavier rainbelt over Tianshan Mountains and its northern piedmont regions,follows from a convergence of the western,the southern with the eastern water vapor transport;The western water vapor transport comes from westerly and the eastern transport is associated with a strong low-level easterly jet stream(LLEJ) extending from Gansu to Xinjiang.The water vapor over Tibetan Plateau penetrates even more northward entering Xinjiang.The water vapor transport is resulted in collocation of the Baikal Lake high on 700 hPa,the southward of Middle-Asia low and eastward shift of Xinjiang high on 500 hPa.Pattern 2,with a main rainbelt over eastern Xinjiang,is supported by the convergence of water vapor both in the east-west and in the south-north;the water vapor comes from the west along westerly,the south from Tibetan Plateau,the north by Boreas and the east by LLEJ from Baikal Lake.Abnormal water vapor transport corresponds to a southeastward extension of Ural high,development and southward moving of middle-Asia vortex,Xinjiang high and developing of the Qaidam high on 700 hPa.Pattern 3,with the heavy rainfall over north to Tianshan Mountains,results from the convergence of water vapor in the east-west;eastern water vapor transport comes directly from LLEJ but originally from the Baikal Lake,the Bay of Bengal,South China and the western Pacific Ocean.The anomalous water vapor transport is associated with a northward extension of the WPSH and a westward shift of Baikal Lake high,a part of tropical abundant water vapor is transported for Xinjiang,and as a result eastern water vapor import takes a dominant role.The eastern transport of anomalous water vapor occurs mainly in the lower troposphere,while the transport of southern water vapor occurs mostly in the upper troposphere.更多还原