[Objective] The research aimed to analyze a rainstorm process in Chongqing. [Methed] Based on precipitation product datasets and NCEP reanalysis data, synoptic situation and diagnostic analysis of a heavy rain process...[Objective] The research aimed to analyze a rainstorm process in Chongqing. [Methed] Based on precipitation product datasets and NCEP reanalysis data, synoptic situation and diagnostic analysis of a heavy rain process during 11 -12 May, 2012 in Chongqing were made, and the diagnostic analysis included dynamic and vapor conditions, instability index, vapor helicity and vapor divergence flux. [ Result] The east-south moving short wave trough and east-north moving southwest vortex were the main synoptic systems causing the heavy rain; the positive vorticity advection before trough and after ridge helped the ascending motion from surface; the southwest stream at 700 hPa provided vapor and energy, promoting and maintaining the intense development of convection; the higher vapor helicity and lower vapor divergence flux were well corresponding with higher precipitation area, and had well temporal correlation, which was significant for forecast of precipitation area and its development; the ascended warm wet stream on the lower air came across the cold air on the upper air, triggering the heavy rain; the Kindex and A index were significant for the heavy rain forecasting. [ Conclusion] The research could provide some references for research and forecast of future rainstorm process in Sichuan and Chongqing.展开更多
基金Supported by National Natural Science Foundation of China(41175046,41205009)
文摘[Objective] The research aimed to analyze a rainstorm process in Chongqing. [Methed] Based on precipitation product datasets and NCEP reanalysis data, synoptic situation and diagnostic analysis of a heavy rain process during 11 -12 May, 2012 in Chongqing were made, and the diagnostic analysis included dynamic and vapor conditions, instability index, vapor helicity and vapor divergence flux. [ Result] The east-south moving short wave trough and east-north moving southwest vortex were the main synoptic systems causing the heavy rain; the positive vorticity advection before trough and after ridge helped the ascending motion from surface; the southwest stream at 700 hPa provided vapor and energy, promoting and maintaining the intense development of convection; the higher vapor helicity and lower vapor divergence flux were well corresponding with higher precipitation area, and had well temporal correlation, which was significant for forecast of precipitation area and its development; the ascended warm wet stream on the lower air came across the cold air on the upper air, triggering the heavy rain; the Kindex and A index were significant for the heavy rain forecasting. [ Conclusion] The research could provide some references for research and forecast of future rainstorm process in Sichuan and Chongqing.
