淡水河流域洪災損失機率風險分析

A PROBABILISTIC FLOOD RISK ANALYSIS OF HOUSEHOLD LOSSES IN THE DANSHUEI RIVER BASIN

本文應用機率風險分析法，以淡水河流域的家戶為研究的範圍與對象， 依序進行洪災的災害度分析、暴露量推估、易損性分析與損失推估， 最後， 以Monte Carlo 模擬法產生家戶損失超越機率曲線， 並計算在幾個假設的決策者之風險接受度下之最大可能損失（PML）與每年損失期望值（AAL）。決策者可以根據這些資訊得知其面臨的洪災損失風險， 進一步依據其決策原則設定一個城市（或流域）可以承擔的洪災損失、洪災防護規模以及擬定適當的風險管理策略。

We employ a probabilistic flood risk analysis to estimate exceedance probability curves, average annual loss (AAL) and probablemaximum loss (PML) of households in the Danshuei River Basin in Taipei. We first establish a set of scenario precipitations, utilize the SOBEKmodel to simulate flood hazards and vulnerabilities, and estimate economic losses for each flood. The aggregate and occurrence exceedance probability curves for household losses are simulated using aMonte Carlo simulation. The average annual loss and the probable maximum loss in the Danshuei River Basin estimated using the aggregate exceedance probability curve can be applied to flood riskmanagement and planning.