Impact of Climate Change on Flood Risk in the Muar River Basin of Malaysia

Twenty-nine flood events have been reported for the last 31 years in the Muar River Basin area of Peninsular Malaysia during the North East Monsoon. This study aims to analyze a 31-year period (from 1980 to 2010) of climatic data from 25 meteorological stations in the Muar River Basin and to identify causes of flooding events in the area. The mean annual rainfall of the 22 rainfall stations in the area was 1707.2 +/- 250.2 mm/year and the mean monthly rainfall was 146.2 +/- 30.9 mm/month. On average, the maximum rainfall was recorded in November and December. The mean annual rain days in the area were 118.4 +/- 12.4 days and the mean annual non-rainy day were 233.6 +/- 14.3 days while the mean monthly rain day in the area was 9.34 +/- 1.72 days. Daily temperature in the area ranged from 21.2 degrees C to 37.7 degrees C. The mean relative humidity was 63.0% and 94.0% during day time and night time respectively. The average evaporation rate of the area was 3.8 mm/day. Results of this study are useful for understanding the climate change in extreme weather events for hydrological and agricultural planning and for flood risk management in the Muar River Basin.