03555nas a2200277 a 450000500170000000800410001703500150005810000310007324500690010426000680017330000230024149000270026450001440029150200580043552023630049365000350285665000220289165000240291370000380293770000430297570000490301870000450306771000400311281000590315285600660321120260817163006.0091209s2009    th uu|m rtt   0|  a1eng d  a.b120708770 aSupatchaya Chuanpongpanich10aApplication of weather radar for rainfall forecasting in Bangkok  aPathum Thani, Thailand :bAsian Institute of Technology,c2009   a197 leaves :bill.1 aThesis ;vno. WM-08-20  aA thesis submitted in partial fulfillment of the requirements for the  degree of Master of Engineering in  Water Engineering and Management  aThesis (M.Eng.) - Asian Institute of Technology, 2008  aWeather radar is one of equipments that can provide real time meteorological data such as rainfall covering large area including big city like Bangkok. A lot of activities in the capital of Thailand depend on the rainfall information in advance. Although, it is difficult to understand rainfall behavior exactly, forecasting can give important information on the trends. The input data from radar images influence in forecasting processes; thus, calibration of radar is necessary and it can provide rainfall intensity (R) from output of radar, reflectivity (Z) values. The objectives of present study are to: calibrate equation of Z-R in the weather radar at Suvarnabhumi, forecast rainfall and develop a procedure to forecast rainfall at a specific location. Radar images from Suvarnbhumi radar covering Bangkok area are used in this study.  The Window Correlation Matching Method (WCMM) is used to determine Z-R relationship and it takes into account the wind effecting to rain measurement and the average reflectivity of different number of pixels in radar image. Thirty six rainfall events with 117 radar images and more than 4 hours of rainfall duration of each event in 2007 and 2008 are used for weather radar calibration and rainfall forecasting. Two radar range 60 kilometers and 240 kilometers are obtained from Thai Meteorological Department (TMD). Twenty raingauge stations are used for calibration. There are nine different cases of WCMM considering time and window space to find the optimal constant values from calibration.  In this study, the calibration of radar from Z-R relationship is obtained with fairly satisfactory values for Z = 44.15R¹·⁰¹⁴ for 60 kilometers radar range and poorly satisfied values for Z = 76.45R⁰·²²²  with 240 kilometers radar range. Critical Success Index (CSI) is found to be 65 % when translation model is developed to forecast five minute time interval of rainfall over all selected fifteen areas in Bangkok such as Siam Paragon, Sukhumvit and Silom. The present study proposed forecasting algorithm which can provide information of rainfall direction, time of rainfall start and rainfall stop. The new indicator, Critical Success Index by Time (CSIT) has been introduced to determine the accuracy of forecast at a particular location. The forecasted result shows that CSIT is about 67% on average 0aRain and rainfallxForecasting 0aRadar meteorology 0aWeather forecasting1 aBabel, Mukand Singh,eChairperson0 aSutat Weesakul,eExamination committee1 aClemente, Roberto S.,eExamination Committee1 aGupta, Ashim Das,eExamination Committee2 aRTG Fellowship, eScholarship donor2 aAsian Institute of Technology.tThesis ;vno. WM-08-20  3Full-Textuhttp://203.159.5.9/ait-thesis/detail.php?q=B04313