LONG-TERM RAINFALL TREND AND DISTRIBUTION IN THE WESTERN REGION OF THE PENINSULAR MALAYSIAHashim, M., Nayan, N., Zahid, M. S., Saleh, Y., Mahat, H., Setyowati, D.L. and Koh, L.S.Abstract Rainfall trend and intensity are essential guides in understanding long-term changes in rainfall. This study aims to identify the trend and intensity of long-term rainfall at the main stations in the western region of Peninsular Malaysia between 1960 and 2010. Rainfall data were collected from 133 stations under the purview of the Department of Drainage and Irrigation of Malaysia. The analytical techniques used were descriptive analysis and the Mann-Kendall Trend Test. The results showed that from 1960 to 2010 the rainfall for all stations were in upward trend. However, Mann-Kendall Test (P=1), showed that the trend was not significant. The average annual rainfall in the western region were classified as moderately wet having to decrease from a range of 1936 mm to 2635 mm, whereas, Daleâs average annual rainfall were in the range of 2540 mm to 2794 mm. The average rainfall variability for the western region during the study period was 699 mm, in contrary; Daleâs average rainfall variability from 1950 to 1959 was 254 mm. The maximum rainfall average for the western region (moderately wet) also lowered by 155 mm (6 per cent) from 1960 to 2010. The rainfall distribution showed that not all areas of the western province in Daleâs study received between 2540 mm and 2794 mm of rainfall annually. The implications of this study is in improving water management, especially in managing and planning the water supply more efficiently. |