Tsunami Vulnerability Mapping Using Remote Sensing and GIS Techniques: A Case Study of Kollam District, Kerala, India

Tsunamis are caused by the displacement of a large volume of water, generally in an ocean or a sea. Submarine earthquakes, volcanic eruptions, underwater explosions, continental shelf landslides, glacier calvings, meteorite impacts, and other powerful submarine disturbances have the potential to generate a tsunami. Tsunami vulnerability zonation and mapping is very important to mitigate the impact due to tsunami disaster. The coastal areas of Kollam district, the present study area were seriously affected by the catastrophic Indian Ocean tsunami of December 26, 2004. This study aims to demarcate tsunami vulnerable areas in Kollam district using Remote Sensing and GIS techniques. A multi criteria decision analysis has been carried out using five parameters, namely land use/land cover, slope, elevation, geomorphology, and distance from shoreline and based on thematic maps prepared with respect to them. The prepared vulnerability map area was classified into five zones: safe, rather safe, moderate, rather vulnerable, and vulnerable. The village boundary was overlaid on the vulnerability map in order to identify and highlight the vulnerable villages. This study provides an interactive method to identify tsunami affected areas after a disaster in addition to mapping tsunami vulnerable areas before a disaster, in an effort to help manage future disasters.