HAZARD ANALYSIS FOR THE SEA LEVEL RISE IN THE SOUTH-WEST COAST OF SRI LANKA

摘要

Sri Lanka is an island country located in South East Asia with about 1650 kilometers of coastal line. Sea level rise is an important issue to investigate as the seas level change could adversely affect the livelihood of the coastal community if necessary mitigation or adaptation strategies are not implemented. The purpose of this work is to identify hazards spatially and temporally, and guide the concerned authorities to formulate coastal zone management policies and prepare mitigation, adaptation and preparedness plans for coastal vulnerability and risk reduction. Three scenarios for the years 2025, 2050 and 2100 were developed considering tidal waves and sea level estimations due to climate change as projected in the IPCC report (2007) and results show that the sea water level at corresponding scenarios were of 1.14, 1.31 and 1.73 m above Mean Sea Level for the three scenarios, respectively. High resolution digital surface model based on LiDAR measurements was used in the study after accuracy assessment with first order control points. However, due to the limited inland coverage of the LiDAR data, digital terrain model generated from contour lines and spot heights was used for the inland areas, which was less accurate than LiDAR data. ALOS/PRISM images were used to update the major and minor roads in the study area, including an expressway. Those updated and existing spatial information were compiled to create Coastal Geo Database in ArcGIS environment, and it provides a platform for identifying the elements at risk. The possible scenarios were further converted to KML format, as a way of expressing geographic annotation and visualization on existing or future web based, two dimensional maps and three dimensional earth browsers.