Identifying the spatial distribution of drought risk zonations in the North Central Province of Sri Lanka

Abstract

Drought is a complex natural phenomenon induced by climate change, and it negatively affects many sectors creating massive socio-economic and environmental losses. North Central Province (NCP) of Sri Lanka is one area undergoing severe drought. Much research has been carried out on drought using different perspectives, but limited research is available on drought risk. The main objectives of this research were to identify the spatial distribution of drought risk and create a map. Multi-Criteria Decision Making (MCDM) method was utilised, where a hierarchy was developed using 16 factors under two main categories, i.e. hazard and vulnerability. Secondary data were collected from different institutions and databases. Pairwise comparison metrics were created to compare the 16 criteria, and Analytic Hierarchy Process (AHP) was used to find the weight of each criterion incorporating the views of 20 experts. Sixteen thematic map layers were created using Geographic Information System (GIS) arc map 10.8 and finally created the drought risk map using the weighted overly technique of GIS. Drought risk was classified into five classes: very low, low, moderate, high and very high. Results were presented by Divisional Secretariat (DS) levels. The results highlighted that drought risk has been distributed over NCP by different proportions. When analysing drought risk spatial distribution of NCP, 13%, 33%.23%, 22% and 9% belong to very low, low, moderate, high and very high categories, respectively. Especially the southern parts of the NCP belong to very low and low categories, and the west and east parts correlate with moderate categories. Towards the north parts of the NCP aligned with high and very high categories. This research will help for the decision-makers and the planers.