Ranking of natural disasters in Sri Lanka for mitigation planning

The purpose of this paper is to propose a methodology for a priori classification of natural disasters that occur in Sri Lanka, through the development of a set of weighted parameters based on the product of the disaster impact and the affected area, in order to prepare mitigation plans.

Experts' opinions were used for developing the parameters. Through a facilitated workshop, the weights of the disasters were obtained from experts involved in disaster mitigation at the local, regional and national levels in Sri Lanka. A correlation analysis was used to determine the most appropriate independent measures of disaster impact and affected area, the product of which was used to rank the identified disasters for further action.

For the pre‐selection of major disasters, the study showcases four weighted parameters, one of which is identified as the best. In total, five disasters have been singled out for further consideration in Sri Lanka. The product of the affected area factor, based on administrative area classification, and the impact factor, out of the two considered, that places a higher weight on minor disasters, is shown to be the best criterion.

The geographical distribution of the participants (experts) does influence the results, and those available for the workshop were not fully representative of all Sri Lanka's provinces.

The paper emphasizes the importance of the consideration of the area impacted rather than the classification, which is based solely on the severity of the impact. The categorization of disasters based on experts' opinions and the related analysis revealed a priority order for planning for certain identified disasters.