A Study of Influencing Systems and Moisture Budget in a Heavy Rainfall in Low Latitude Plateau in China during Early Summer

• Published in: Advances in atmospheric sciences Vol. 24; no. 3; pp. 485 - 502
• Main Author: 董海萍 赵思雄 曾庆存
• Format: Journal Article
• Language: English
• Published: Dordrecht Springer Nature B.V 01.05.2007; Graduate University of the Chinese Academy of Sciences, Beijing 100039; Air Force Meteorological Center, Beijing 100843%Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing 100029; Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing 100029
• Subjects: Atmospheric sciences; Moisture; Rain; Rainfall; Studies; Troposphere; Water content; Water vapor; 云贵高原; 低纬度高原; 夏季初期; 影响系统; 水汽收支; ISW, Bangladesh, Bengal Bay; China, People's Rep; moisture budget; Yunnan-Guizhou Plateau; mesoscale systems; heavy rainfall
• ISSN: 0256-1530; 1861-9533
• DOI: 10.1007/s00376-007-0485-z

Analysis of a heavy rainfall in a lower latitude plateau and characteristics of water vapor transportation have been conducted by using conventional data and denser surface data. The results show： （1） the heavy rainfall was caused by a series of mesoscale systems under favorable large-scale conditions when the warm moister air and cold air interacted with each other. At the same time, the coupling between the upper- and lower-level jets was revealed. It is also found that there exists some different characteristics among the main influencing systems of heavy rainfalls in Yunnan, such as the Indian-Myanmar trough and the path of the cold air, compared with those in East and South China. （2） The interaction between mesoscale convergence lines near the ground may be a possible triggering mechanism for the occurrence of mesoscale systems, and the dynamical and thermal dynamical structure of the mesoscale systems was very obvious. The convergence lines may relate closely to the terrain of Yunnan, China. （3） The computation of the water vapor budget reveals that the primary source of water vapor supply for heavy rainfall was in the Bay of Bengal. In this case, the water vapor could be transported into Yunnan even though the amount of water vapor was less than that in the lower troposphere in East and South China. In addition, the analysis for three-dimensional air parcel trajectories better revealed and described the source location and the transportation of water vapor to Yunnan.