Analysis and Prediction of Local Heavy Rainfall in Mountainous and Urban Area

在本项目中，研究人员提出了强降雨预报系统，并对局地暴雨进行了分析。用两种方法对局地强降水进行了分析。首先，调查人员在白牛强降雨条件下，主要利用无线电探空仪和雨量计观测到了几次严重的再入流事件。其次，研究人员开发了一个地形跟随坐标的积云模型和详细的微物理模型。使用该模型，调查人员模拟了强降雨事件。分析的过程和结果如下：1)在福井县库珠流河流域进行了以百牛锋为主的强降雨条件下的水文气象观测。观察期为1996年6月20日-30日和1997年7月2日-10日。观测使用了射电卫星(每小时两到三次)、光学和正常雨量计(一次标准杆一到十分钟)、汽车X波段雷达(连续).2…以观测资料为初始资料和验证资料，计算了具有详细云微物理特征的数值积云模式。研究人员分析了地形、风场、大气和热力稳定性以及水汽对控制积云产生和消散的云微物理过程的影响。作为分析的结果，研究人员得出了冰雹产生量是积云降雨量的重要因素。此外，他们发现水汽和垂直风是冰雹产生的重要因素。3)研究人员提出GPS是适合水汽观测的观测系统。此外，为了利用GPS获得积云尺度的水汽扰动，他们开发了一种新的方程系统。调查人员发现，该方程系统使用数值模拟数据取得了良好的结果。他们还利用观测到的GPS数据研究了方程系统的效率。研究发现，在观测条件较好的情况下，该方程组是有效的。研究还发现，观测数据受多种误差源的影响。最后，提出了利用多普勒雷达垂直风场观测和GPS水汽观测作为强降雨预报的有效观测系统。较少

In this project, investigators have proposed the severe rainfall prediction system as well as they have analyzed the local heavy rainfall. The analysis of local heavy rainfall has been done by twoapproaches. First, investigators observed several severe reinfall events mainly with radio sonde and rain gage under condition of severe rainfall in Baiu. Second, investigators developed a cumulus cloud model which has terrain following coordinate and detailed microphysics model. Using the model, investigators simulate severe rainfall events. The processes and result of the analysis is as follows ;1) Hydrological and meteorological observations have been done under condition of severe rainfall which came mainly from Baiu fronts at the Kuzuryu river basin in Fukui Prefecture. Observation period is June 20-30,1996 and July 2-10,1997. Observations have been done with radio sonds (two to three hourly), optical and normal rain gage (once par one to ten minutes), car bone X band radar (continuous).2 … More ) Numerical cumulus model which has detailed cloud microphysics have been computed with observation data as initial and verification data. Investigators analyze the effect of topography, wind field, atmospheric and thermodynamic stability and water vapor on cloud microphysical processes which control the cumulus generation and dissipation. As results of the analysis, investigators obtained results that the amount of hail generation is important factor for rainfall amount from cumulus. Moreover, they found that water vapor and vertical wind are important factor for hail generation.3) Investigators proposed that GPS is suitable observation system for water vapor observation. Moreover, they developed a new equation system in order to obtain the water vapor disturbance of cumulus scale using GPS.Investigators found that the equation system made good results using numerical simulation data. They also investigated efficiency of the equation system using observed GPS data. Investigation found that the equation system is effective under good observation condition. They also found that the observation data are affected by many kind of error sources.Finally, the vertical wind field observation by Doppler radar and water vapor observation by GPS are proposed as a effective observation system for severe rainfall prediction. Less