ASSESSMENT OF CLIMATE CHANGE IMPACTS ON INLAND FLOODS VULNERABILITY -SEMINAR ON CLIMATE CHANGE VULNERABILITY & ADAPTATION (2015)
Economics of Climate Change in Malaysia (ECCM) study for water resources sector conducted in 2012 by National Hydraulic Research Institute of Malaysia (NAHRIM) is the starting point and first attempt to quantify flood and irrigation water supply vulnerability due to climate change. In this study, the methodology for assessing inland flooding vulnerability by incorporating climate change factor (CCF) was developed for four selected river basins namely Kedah in northern Peninsular Malaysia; and Pulai, Skudai and Tebrau which are located in the south. CCF, defined by the ratio of future to historical design rainstorm, is a key element in the methodology. Now by using the same methodology and approach, the study is expanded to five more main river basins in Peninsular Malaysia: Kerian, Setiu, Pahang, Muar and Kesang river basins. This selection represents various catchment sizes and types, subject to the availability of fine resolution elevation data. The assessment focused on 4 scenarios namely baseline with current landuse, baseline with future landuse, climate change with current landuse and climate change with future landuse. The key parameter which is the projected future rainfall was downscaled from 3 different coupled land-atmosphere-ocean GCMs (ECHAM5, CCSM3 and MRI) under four IPCC SRES greenhouse gas emission scenarios (B1, A1B, A2 and A1Fi), giving a combination of 15 climate projections data over Peninsular Malaysia. The catchment CCF in association with average recurrence interval (ARI) were derived for two time horizons (2030 and 2050) for the 5 river basins. For example, the derived 100 years ARI CCF are found to be ranging from 1.21 to 1.65 and 1.28 to 1.87 for time horizons 2030 and 2050 respectively. In turn, under baseline with climate change scenario, by means of hydrologic and hydrodynamic modelling, the total inundated flood areas in the vicinity of 5 river basins are expected to increase from 5.4% to 45.7% and 6.7% to 60.0% for each respective time horizon. The highest increment in inundation area is Muar river basin which ranges from 302 km2 to 484 km2, which is approximately 60%.
Authors
Abstract
Economics of Climate Change in Malaysia (ECCM) study for water resources sector conducted in 2012 by National Hydraulic Research Institute of Malaysia (NAHRIM) is the starting point and first attempt to quantify flood and irrigation water supply vulnerability due to climate change. In this study, the methodology for assessing inland flooding vulnerability by incorporating climate change factor (CCF) was developed for four selected river basins namely Kedah in northern Peninsular Malaysia; and Pulai, Skudai and Tebrau which are located in the south. CCF, defined by the ratio of future to historical design rainstorm, is a key element in the methodology. Now by using the same methodology and approach, the study is expanded to five more main river basins in Peninsular Malaysia: Kerian, Setiu, Pahang, Muar and Kesang river basins. This selection represents various catchment sizes and types, subject to the availability of fine resolution elevation data. The assessment focused on 4 scenarios namely baseline with current landuse, baseline with future landuse, climate change with current landuse and climate change with future landuse. The key parameter which is the projected future rainfall was downscaled from 3 different coupled land-atmosphere-ocean GCMs (ECHAM5, CCSM3 and MRI) under four IPCC SRES greenhouse gas emission scenarios (B1, A1B, A2 and A1Fi), giving a combination of 15 climate projections data over Peninsular Malaysia. The catchment CCF in association with average recurrence interval (ARI) were derived for two time horizons (2030 and 2050) for the 5 river basins. For example, the derived 100 years ARI CCF are found to be ranging from 1.21 to 1.65 and 1.28 to 1.87 for time horizons 2030 and 2050 respectively. In turn, under baseline with climate change scenario, by means of hydrologic and hydrodynamic modelling, the total inundated flood areas in the vicinity of 5 river basins are expected to increase from 5.4% to 45.7% and 6.7% to 60.0% for each respective time horizon. The highest increment in inundation area is Muar river basin which ranges from 302 km2 to 484 km2, which is approximately 60%.
Citation
IR. MOHD ZAKI MAT AMIN, NURUL HUDA MD. ADNAN, GOH YEE CAI, IR. MARINI MOHAMAD IDERIS . 2015. ASSESSMENT OF CLIMATE CHANGE IMPACTS ON INLAND FLOODS VULNERABILITY -SEMINAR ON CLIMATE CHANGE VULNERABILITY & ADAPTATION (2015). Digital NAHRIM Publication Repository.