INUNDATION IMPACTS DUE TO SEA LEVEL RISE AND THE ADAPTATION ASSESSMENTS FOR COASTAL PROTECTION

Abstract

 Inundation impacts due to sea level rise caused by climate change were assessed globally using multiple global climate model outputs. In particular, the assessment accuracy was improved by upgrading the data for coastlines according to a method previously proposed by the authors. As a result, 750 − 820 × 10³ km² of coastal land was estimated to be inundated globally by 2100 under Representative Concentration Pathway 8.5. A new method for estimating the adaptation cost by building coastal dikes was applied, and economic damage and adaptation costs were compared under several adaptation scenarios. If all global inundation were avoided only by building coastal dikes, the adaptation cost was estimated to be six times as much as the inundation damage cost at the end of this century. This study’s consideration of the adaptation options against global inundation suggested that multiple options, such as “green infrastructure” and other accommodations, should be implemented.