RESEARCH ON VERTICAL SECTION OF SHEAR VORTICITY AND DIABATIC HEATING WITH WUHAN TORRENTIAL RAIN IN 1998
Zhou Bing (LASG, Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing 100029) Xu Haiming Tan Yanke He Jinhai (Nanjing Institute of Meteorology, Nanjing 210044)
Comparing the different vorticity components on Wuhan torrential rain in 1998, the results show that zonal shear vorticity has a corresponding connection with heavy rainfall center while the upper-negative shear vorticity develops and the low-positive vorticity increases. Analysis of case and statistics present that the development of zonal shear vorticity over 200 hPa is one day ahead of heavy rainfall occurrence. Meantime, the high apparent heat source (Q 1) and moist sink (Q 2) as well as strong ascending motion go with torrential rain stage. The source center is located at 450 hPa, and the sink center at 600 hPa. Evidences suggest that the transportation term plays an important role in atmospheric diabatic heating processes. However, the local variation term is small and reverse to advection term in apparent heat source vertical section, so it is often ignored, but it can not be neglected in moist sink.