— Rain gauge and weather radar is a tool to measure rainfall depth. But, weather radar cannot measure the rainfall depth directly as oppose to rain gauge. Therefore, an empirical relationship between reflectivity (Z) and rainfall rate (R), called the Z-R relationship (Z=ARb), is commonly used to assess the rainfall depth using radar. Using the optimization technique, new relationship for northern of Peninsular Malaysia was developed. Using the daily rainfall data, calibration process has been performed by varying the value of A and fixed the exponential b to 1.6. The calibration process done, new climatological Z-R relationship, Z=40R1.6 indicates the closeness between radar rainfall and gauge rainfall. To justify the new relationship, validation process has been performed using the calibrated equation which shows the value of Mean Error, Absolute Mean Error, Root Mean Square Error and Bias within the acceptable statistical indicators with the values of 2.65, 3.29, 3.81, and 0.85 respectively.
— Z-R relationship, radar rainfall estimation, Alor Star Radar, optimization.
Mahyun A. W. is with School of Environmental Engineering, Universiti Malaysia Perlis, 02600 Arau, Perlis, Malaysia. She is also with School of Civil Engineering, Universiti Sains Malaysia, Engineering Campus, 14300 Nibong Tebal, Pulau Pinang, Malaysia (e-mail: email@example.com).
Abdullah R., Abustan I., and Nur Atiqah A. A. are with School of Civil Engineering, Universiti Sains Malaysia, Engineering Campus, 14300 Nibong Tebal, Pulau Pinang, Malaysia (e-mail: firstname.lastname@example.org, email@example.com, firstname.lastname@example.org).
Adam M. K. M. is with Malaysian Meteorological Department, Main Meteorological Office, Kuala Lumpur International Airport, Selangor Darul Ehsan, Malaysia (e-mail: email@example.com).
Cite: Mahyun A. W., Abdullah R., Abustan I., Adam M. K. M., and Nur Atiqah A. A., " The Radar-Rainfall Relationship for Northern Region of Peninsular Malaysia," International Journal of Innovation, Management and Technology vol. 5, no. 2, pp. 143-147, 2014.