Economic costs and impacts of climate-induced sea-level rise and storm surge in Canadian coastal provinces: a CGE approach

We estimated the economic costs and impacts of future sea-level rise (SLR) and storm surge due to climate change in Canada's coastal provinces using regional, dynamic computable general equilibrium models that track provincial welfare, GDP, trade, prices and inputs over the 2009-2054 period. We also assessed the economic costs of coastal adaptation investments, to determine whether such investments can be justified on economic grounds. Results indicated that SLR and storm surge could cost Canada in the range of $4.6-$25.5 billion in present value welfare, and between $53.7 and $108.7 billion in present value GDP. We found significant variation in costs and impacts across coastal provinces, with some provinces such as Newfoundland and Labrador experiencing only marginal costs/impacts, and others such as British Columbia experiencing costs as high as $21 billion in welfare over the period. Coastal adaptation investments were supported on economics grounds. Overall, this study provides the first (and preliminary) provincial economic impact estimates of climate-induced SLR and storm surge, as well as adaptation investments, in Canada. Additional research is needed to refine the analysis in order to produce reliable estimates that can be used to guide coastal adaptation policies in Canada.