| The climate characteristics and the spatiotemporal distribution of hail in Chongqing in nearly 50 years have been analyzed in order to improve the weather analysis and forecast the hail over Chongqing, to strengthen multi-source meteorological data in Chongqing hail of application, with a long series of historical meteorological records from 34 counties of Chongqing and MICAPS conventional weather chart from 34 meteorological stations in Chongqing.For the first time hail weather processes are sorted; The beneficial circulation background and main environmental field characteristics are summarized; and the motion pathes of hail are given.In addition, by using doppler radar data and FY2C satellite retrival products between 2008 and 2009 years, we analyse all typical examples of hail during this period, explores the application in the hail forecasting and analysis in Chongqing with Doppler radar and satellite retrieval products.At the same time, we analyse intensively some characteristics of a typical case of hail on June 5,2008,such as the thermal structures, dynamic background and physical mechanism, radar echo characteristics, the hail cloud macro-and micro-physical structures and the evolution regulation.The main research contents and results are as follows.In the paper we analyze the statistical characteristics of the climate in Chongqing hail. The results show that the hail of chongqing in eastern is more than in western.northeast of the most frequent; the hail days vary is heterogeneous in the past 50 years,and has significant increasing after 1980s; inter-monthly variation of hail shows the double peaks, one peak from April to May and the other from July to August. The analysis also shows that hail weather focus on local convection and systematic convection takes second place. The circulation background of systematic convection has three types including cold vortex, northwest airflow and upper trough, the northwest airflow is about 62%. In addition, this study also gives nine motion paths of hail and puts forward some ways to improve the effectiveness of weather modification.Using CINRAD-SA Doppler radar data and MICAPS conventional weather chart, as well as FY2C Satellite retrival products, a supercell storm occurring in Chongqing on June 5,2008 is analyzed. The result shows that the super-cell storm generated by the mechanism of the typical "the upper-level is dry and cold, as well as the low-level is warm and wet", and hail shooting region is located in the export zones of low-level jet and wind convergence area. There are many supercell features of Doppler radar echoes, such as hookecho, bounded weak echo region, vault, meso-cyclone, gust front and etc. We also find that the vertical integration of liquid water content(VIL) increasing abruptly is ahead of two or three volume scan, this result has certain indicating significance on hail forecasting.On the other hand, the paper makes an assay of the supercell storm based on the retrival products of FY2C satellite, and we think that the products of cloud effective particle radius can carefully describe the meso and small scale cloud microphysical structure, its great value is consistent with hail shooting area, and the result is important to hail forecasting.Radar echo identification of hail cloud should be comprehensively analysed, from the aspacts of echo intensity, high echo top, VIL values and characteristics, hail index, velocity field characteristics of all-round consideration. The key indicators of monitoring and warning are as follows:echo intensity is greater than 50dbz; tall of echo top is over 11km; the VIL value is greater than 44 kg/m2; the VIL value-added is more than 15kg/m at a volume scan and then the VIL value is over 50kg/m; Hail index products are solid triangles during a few consecutive sweeps; there are some strong wind convergence or mesoscale cyclone.In addition, the abrupt increasing of vertical integration of liquid water content(VIL) is ahead of two or three volume scan, this result has certain indicating significance on hail forecasting and timing of artificial hail suppression operations.In the paper we first explore the application of satellite retrieval products in Chongqing hail and initially give some identification Hail feature parameters. The monitoring and warning key indicators are as follows:cloud top height is over 9km, cloud top temperature is below-30℃;cloud effective particle radius is over 36μm; cloud optical thickness is over 30; liquid water path is over 700g/m. In particular, the cloud effective particle radius product is most useful, and the possibility of hailfall is large, on the condition that the cloud effective particle radius is very great and the proportion of big particles is very high.These correlation studies are beneficial to deepen our comprehensive knowledge of hail climate characteristics in Chongqing, to improve the hail forcasting ability and to enhance the capability of identifying operating conditions of artificial hail suppression, as well as to expand the application fields of satellite retrieval products.
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