Improved watershed runoff estimation using radar-derived rainfall in Peninsular Malaysia

• Main Authors: Yacoob, Waleed, Mohd Som, Mohd Amin, Ahmad Dahlan, Abdul Rahman, Abdul Rahman, Irdawati, Hasan, Saliza
• Format: Conference or Workshop Item
• Language: English
• Published: 2009
• Subjects: S Agriculture (General)
• Online Access: http://irep.iium.edu.my/6075/1/iCREATE086.pdf; http://irep.iium.edu.my/6075/; http://www.intimal.edu.my/icreate2009/
• Institution: Universiti Islam Antarabangsa Malaysia

In traditional hydrologic and water resource applications, rain gauges are the commonly used rainfall measuring device. Normally these rain gauges are installed at convenient locations. Rain gauges provide direct rainfall measurements over small areas. Malaysia is a humid tropical country with more than 60% of land area covered with forest. Hence, using rain gauges to determine the spatial distribution of watershed rainfall may not be the best technique. Weather radar provides measurements of rainfall over large area at high spatial resolution and frequent intervals. These characteristics make weather radar a useful system for rainfall estimation. The main objective of this study was to develop a technique to improve the performance of hydrological models to estimate runoff more accurately using radar-derived rainfall data incorporating GIS. The six weather radar stations (Subang, Alor Setar, Butterworth, Kluang, Kota Bharu and Kuantan) available in the Peninsular Malaysia were considered in this study. Radar-derived rainfall data was implemented to generate more representative rainfall distribution maps. Hence, considerable improvements were found in the watershed runoff estimation using radar rainfall compared to the available rain gauges.