Department of Economics, University of Western Ontario, London, ON, Canada.
Risk Anal. 2019 Jun;39(6):1314-1341. doi: 10.1111/risa.13285. Epub 2019 Feb 14.
Coastal cities around the world have experienced large costs from major flooding events in recent years. Climate change is predicted to bring an increased likelihood of flooding due to sea level rise and more frequent severe storms. In order to plan future development and adaptation, cities must know the magnitude of losses associated with these events, and how they can be reduced. Often losses are calculated from insurance claims or surveying flood victims. However, this largely neglects the loss due to the disruption of economic activity. We use a forward-looking dynamic computable general equilibrium model to study how a local economy responds to a flood, focusing on the subsequent recovery/reconstruction. Initial damage is modeled as a shock to the capital stock and recovery requires rebuilding that stock. We apply the model to Vancouver, British Columbia by considering a flood scenario causing total capital damage of $14.6 billion spread across five municipalities. GDP loss relative to a no-flood scenario is relatively long-lasting. It is 2.0% ($2.2 billion) in the first year after the flood, 1.7% ($1.9 billion) in the second year, and 1.2% ($1.4 billion) in the fifth year.
近年来，世界上的沿海城市都经历了重大洪灾带来的巨大损失。由于海平面上升和更频繁的剧烈风暴，预计气候变化将增加洪水发生的可能性。为了规划未来的发展和适应措施，城市必须了解这些事件相关的损失规模，以及如何减少这些损失。通常，损失是根据保险索赔或对洪水灾民的调查来计算的。然而，这在很大程度上忽略了经济活动中断造成的损失。我们使用前瞻性的动态可计算一般均衡模型来研究当地经济对洪水的反应，重点关注随后的恢复/重建。初始损失被建模为资本存量的冲击，而恢复需要重建该存量。我们通过考虑一个造成不列颠哥伦比亚省温哥华五个城市总计 146 亿美元的资本损失的洪水情景来应用该模型。相对于没有洪水的情景，GDP 损失是相对持久的。洪水发生后的第一年损失 2.0%（22 亿美元），第二年损失 1.7%（19 亿美元），第五年损失 1.2%（14 亿美元）。
