Study on factor affected the radar-rainfall relationship parameter: case study on radar Alor Star

Abstract

Malaysia has long used the equation Marshall and Palmer which was created since 1948. Therefore, this project will find the new parameter for radar of Alor Setar. Thus, the project is to identify factors that affect the rain-radar relationship. Marshall and Palmer equation is written in the form Z=200R1.6 .According to research studies previously, Marshall and Palmer are believed is not relevant for use in Malaysia. At the same time, making predictions for rain are very important. This is because; it can prevent an impending natural disaster. Cataclysm is a medium where we will get a big loss. Therefore, avoid is better than cure. With it, the renewal of the equation parameters is needed because of the difference between the average rate and the average rate of precipitation radar rain gauges have large errors in the Marshall and Palmer. This study will show that equation Marshall and Palmer is no longer suitable to be used in Malaysia for several factors that need to be identified through 4 cases; using an average rate of 14 rain gauges calibration with radar Alor Star, choose randomly an average rate of 7 rain gauge calibration with radar Alor Star, using the upstream of Perlis rain gauge calibration with radar Alor Star and use the downstream of Perlis rain gauge calibration with radar Perlis Alor Star. By using sensitivity analysis 4 statistical measures can determine the parameters Z-R. Then, the calibration process is carried out to get the new value of parameter Z-R. The value resulting from this process is A=36. After that, it is written in the form of the equation of Z=36R1.6 and through a verification process showed that the new Z-R equation is appropriate to estimate rainfall radar in Malaysia especially in Alor Star. The conclusion, the new Z-R equation of Z=36R1.6 will be able to improve the quality and the accuracy budgetary rain can prevent the occurrence of natural disasters.