| A case study of Bangladesh presents a methodological possibility based on a global approach for assessing river flood risk and its changes considering flood hazard, exposure, basic vulnerability and coping capacity. This study consists of two parts in the issue of flood change: hazard assessment (Part 1) and risk assessment (Part 2). In Part 1, the hazard modeling technology was introduced and applied in the GBM basin to quantify the change of 50- and 100-year flood hazard in Bangladesh under the present (1979-2003) and future (2075-2099) climates. Part 2 focuses on estimating flood risk in terms of affected people and damaged rice crops due to 50-year flood hazard identified in part 1, and quantifying the flood risk changes between presence and absence of existing water infrastructure (i.e., embankment). For flood risk assessment in terms of rice crop damages, extracted rice paddy area and developed flood stage-damage curves are used for maximum risk scenarios as a demonstration of risk calculation from the present to future climates. The proposed methodology is applicable anywhere in the world. The preliminary results in Bangladesh show that a propensity of flood risk change strongly depends on the temporal and spatial dynamics of exposure and vulnerability such as distributed population and effectiveness of water infrastructure. |
