Physical and Economic Consequences of Sea-Level Rise: A Coupled GIS and CGE Analysis Under Uncertainties

This paper develops a modelling framework that links GEMINI-E3, a multi-regional, multi-sectoral computable general equilibrium model with a cost-benefit analysis approach at local level using geographical information system tools to assess the physical and economic consequences of sea-level rise (SLR) in the twenty first century. A set of future scenarios is developed spanning the uncertainties related to global warming, the parameters of semi-empirical SLR estimates, and coastal developments (cropland, urban areas and population). The importance of incorporating uncertainties regarding coastal development is highlighted. The simulation results suggest that the potential development of future coastal areas is a greater source of uncertainty than the parameters of SLR itself in terms of the economic consequences of SLR. At global level, the economic impact of SLR could be significant when loss of productive land along with loss of capital and forced displacement of populations are considered. Furthermore, highly urbanised and densely populated coastal areas of South East Asia, Australia and New Zealand are likely to suffer significantly if no protective measures are taken. Hence, it is suggested that coastal areas needs to be protected to ameliorate the overall welfare cost across various regions.