SCGEモデルを用いた大規模洪水の経済被害推計

Abstract

我が国では，自然災害に見舞われるリスクが高く，自然現象がもたらす被害を如何に抑制するかが問われてきた．自然災害の中でも，南海トラフ巨大地震や首都直下型地震による被害については，近年，様々に予測されているが，その一方で，大規模洪水がもたらす被害，特に経済被害については，定量的な予測が十分になされていない状況である．そこで，本研究では，SCGEモデル（空間的応用一般均衡モデル）を用いた大規模洪水による経済被害の推計手法を考案し，東京・大阪・東海の3つの地域における洪水シナリオに基づいて経済被害の推計を行うことを目的とした．Japan faces great risk of natural disasters and it is concerned that there will be other large-scale disasters which may cause fatal damage to important functions for maintaining administration as well as social and economic systems. In order to avoid such kind of situations, recently it is said to be important to make resilient national land. However, estimations of damage such as economic loss caused by largescale floods have not been done yet, even though these are quite important to assess the validity of measures to promote National Resilience. Therefore, this study conducted estimations of economic loss due to inundation caused by large-scale floods in Tokyo, Osaka, and Tokai areas according to the expected floods scenarios by a spatial computable general equilibrium (SCGE) model. As a result of that, serious damage to the economy triggered by inundation in Tokyo, Osaka, and Tokai areas was estimated. The result suggests the great need of mitigation measures against large-scale floods.