Post-disaster assessment of impact of cyclone Lehar in South Andaman Island

Disasters are the events which devastate human lives, properties and natural ecosystems; cyclones are frequent events in tropical countries which have adverse impacts on coastal areas. The present study evaluates the impact of cyclone Lehar post-disaster in the South Andaman Island using geographic information system (GIS) and remote sensing techniques. Cyclone Lehar originated in the Andaman Sea and had a major impact on the South Andaman Island. Digital elevation model was used to create elevation and slope maps of the study area. These maps were used to study the impacts of floods, landslides, storm surges and runoff. Land-use and land-cover features were mapped and overlaid with this model for preparing the vulnerability map for various outcomes of the cyclone. Preliminary impact assessments were made in these identified vulnerable areas and also throughout the study area. Finally the results were interpreted with vulnerability map prepared using the GIS technique which shows that most of the affected areas are correlated with the vulnerability map. Cyclone Lehar had adverse impacts on natural ecosystems such as forests, mangroves and sandy beaches. It also damaged man-made features such as settlements, infrastructure, agricultural fields and plantations. This study proves spatial technologies are the indispensible tools for post-disaster planning and impact assessment.