Local conditions wind multiplier map as supporting tool in windstorm hazard assessment for Malaysian districts (Study Case: Kuantan, Pahang)

Abstract

Local conditions wind multiplier map considered as one of the essential supporting tool in windstorm disaster management because throughthis map effected of local conditions to windstorm intensity (gust/wind speed)in anygrid area of 1 km x 1 km can be made known. Local conditions multiplier for each grid area need to be multiplied with predicted windstorm intensity from the source (downdraft) in order to determine the actual intensity on land surface. Next, through the actual intensity, potential damages can be identified. Information regarding potential damages enables local authorities and public in the affected area to make early preparation in minimizing the impacts caused by windstorm occurrence. Production of this map is according to severe wind gust risk assessment which taking into account of terrain (roughness), shielding multiplier and topographic (hill-shape) factors. Multiplier for each factor are based on the Malaysian Standard (MS1553: 2000) and Australian/New Zealand standard (AS/NZS1170.2: 2011). Kuantan District has been selected as a case study based on two factors, one of a district in Malaysia with highest number of windstorm occurrences and the only district that has been studied about its land cover roughness. As a matter of fact, this article is to provide guidance in producing supporting tool that could be as added value in windstorm disaster management in the future.