ADVANCES IN ATMOSPHERIC SCIENCES, VOL. 24, NO. 6, 2007, 1049–1059 The Major Research Advances of Mesoscale Weather Dynamics in China Since 2003 LU Hancheng ∗ 1 (陆汉城), GAO Shouting 2 (高守亭), TAN Zhemin 3 (谈哲敏), ZHOU Xiaoping 2 (周晓平), and WU Rongsheng 3 (伍荣生) 1 Meteorological College, PLA University of Science and Technology, Nanjing 211101 2 Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing 100029 3 Department of Atmospheric Science, Nanjing University, Nanjing 210093 (Received 30 January 2007; revised 10 October 2007) ABSTRACT This paper reviews the main theoretical progress of mesoscale weather dynamics since 2003, including: (1) The dynamic mechanisms of balanced and unbalanced flow are applied to study the genesis and development problems of mesoscale circulation. The symmetric instability and transverse-wave instability are analyzed in line and vortex atmosphere convection, and further research has been done on nonlinear convective symmetric instability. The interaction between forced convection and unstable convection and the wave characteristics of mesoscale motion are also discussed. (2) Intermediate atmosphere dynamic boundary layer models are developed. The complicated nonlinear interaction is analyzed theoretically between the atmospheric boundary layer and the free atmosphere. The structure of the topography boundary layer, atmospheric frontogenesis, the structure and circulation of the low-level front and other boundary layer dynamic problems are discussed. (3) The formation and development of meso-β-scale rainstorms under the background of the East-Asia atmosphere circulation are diagnosed with the variation of MPV (moist potential vorticity) anomalies. And some physical vectors are modified and applied in the moist atmosphere. Key words: mesoscale dynamics, mesoscale circulation, mesoscale numerical simulation and diagnoses DOI: 10.1007/s00376-007-1049-y 1. Introduction With Chinese economic boom since 2003, research on mesoscale meteorology have acquired more national funding. Additionally, due to the marked progress of modern atmosphere sounding technology and com- puter technology, significant advances have been made in the research on mesoscale severe weather. In addi- tion, frequent occurrences of severe storm weather and rainstorm weather in recent years have attracted con- siderable public attention because of the catastrophic influence to the national economy and people’s lives. So the study on the mechanism research and warning technology of mesoscale severe weather are of great concern. With the methods of observation analysis, dynamic diagnoses and numerical forecasting, Chinese meteorologists probe deeply into the organization of mesoscale convective systems (MCSs), in which the dynamic theory of deep and moist convection closely associated with mesoscale severe weather under the condition of the East-Asia atmosphere circulation has made innovative advances. This paper reviews the progress of research on mesoscale weather dynamics since 2003. In the next section, we summarize achievemnets made in the re- search on the dynamic mechanism of mesoscale cir- culation. Section 3 reviews major results on Ekman boundary layer dynamics. Section 4 concludes the main progress in rainstorm and moist atmospheric dy- namics. A brief summary is given in the final section. 2. The dynamic mechanism of mesoscale cir- culation Observational research shows that mesoscale MCSs are convection storms formed by organic cumulus con- * Corresponding author: LU Hancheng, hc lu@126.com or hancheng.lu@gmail.com