Evaluation of Long-Term Trends of Rainfall in Perak, Malaysia

This study aimed to examine the spatiotemporal seasonal and annual trends of rainfall indices in Perak, Malaysia, during last 35 years, as any or spatial variability may influence regional hydrological cycle water resources. Mann–Kendall Sequential (SMK) tests were used assess trends. Precipitation concentration index was estimate variations concentration, Theil–Sen’s slope estimator determine rainfall. It found that most are showing decreasing trends, it prominent for southwest monsoon season with a rate 2.20 mm/year. The long-term showed declined by 0.29 mm/year monsoon. In contrast, northeast inter-monsoon seasons slight increases. Rainfall decreased gradually from 1994 2008, trend became more pronounced 2008. On basis, have shifted western regions (i.e., −19 mm/year) southeastern 10 mm/year). Overall, slightly observed Perak Malaysia.