Regional Modeling of Climate Change Impact on Peninsular Malaysia Water Resources Jamalluddin bin Shaaban, Ahmad

The future projections of climate change by means of Global Climate Models (GCMs) of the Earth provide fundamental coarse-grid-resolution hydroclimate data for studies of the impact of climate change on water resources. We report on a study where the climate change simulations of Coupled Global Climate Model of the Canadian Center for Climate Modeling and Analysis were downscaled by a Regional Hydroclimate Model of Peninsular Malaysia to the scale of the subregions and watersheds of Peninsular Malaysia in order to assess the impact of future climate change on its water resources. Based on simulations of hydroclimatic conditions during the 1984–1993 historical and 2025–2034, 2041–2050 future periods it is concluded that the overall mean monthly streamflow is about the same during the future period and during the historical period for most of the watersheds except Kelantan and Pahang. In those two watersheds there is significant increase in the overall mean monthly streamflow during the future period. It is also clear that the high flow conditions will be magnified in Kelantan, Terengganu, Pahang and Perak River watersheds during the wet months, while low monthly flows will be significantly lower in Selangor and Klang watersheds during the dry months in the future.