Analisis Hujan Jangka Panjangdari tahun 1960-2010 di Wilayah BaratSemenanjung Malaysia

Analysis of Long-Term Rainfall from 1960-2010in the West Peninsula Malaysia

Abstract

This study aimed to verify the characteristics of the western region rainfall that was established by Dale in 1959. The focus is to identify trends and long-term rainfall intensity in the western region from 1960 to 2010 which is classified as wet areas. Data from rainfall stations located in the western region derived from the Malaysia Meteorological Department and the Department of Irrigation and Drainage was used in this study. Annual rainfall data for 133 stations from 1960 to 2010 were examined using descriptive analysis and Mann- Kendall test. Based on Mann-Kendall (S=1), although not significant, the results of rainfall data from 1960 to 2010 from all stations have shown increased in annual precipitation trends. Range of average annual rainfall for the area western region classified as medium wet have decreased between 1936 mm to 2635 mm compared to an average annual rainfall ranges by Dale, between 2540 mm to 2794 mm. However, variation in mean rainfall for the western region is increasing by 699 mm compared to average rainfall variations by Dale of 254 mm between the years 1950 to 1959. The maximum rainfall in 1960 and 2010 for the western region (wet medium) was reduced by 155 mm (6 %). The study also showed that La-Nina phenomenon and the El- Nino rains have influenced variations in the western region in 1966, 1976, 1983, 2000 and 2005. There are certain areas in the western region of extreme rainfall (Bukit Larut, Selama, Batu Kurau) and a little rain (Lawin, Tanjung Karang, Sungai Besar).