Wing Oliver E J, Bates Paul D, Smith Andrew M, Sampson Christopher C, Johnson Kris A, Fargione Joseph, Morefield Philip
School of Geographical Sciences, University of Bristol, Bristol, BS8 1SS, United Kingdom.
Fathom, Engine Shed, Station Approach, Bristol, BS1 6QH, United Kingdom.
Environ Res Lett. 2018 Feb 28;13(3):1-7. doi: 10.1088/1748-9326/aaac65.
Past attempts to estimate rainfall-driven flood risk across the US either have incomplete coverage, coarse resolution or use overly simplified models of the flooding process. In this paper, we use a new 30 m resolution model of the entire conterminous US with a 2D representation of flood physics to produce estimates of flood hazard, which match to within 90% accuracy the skill of local models built with detailed data. These flood depths are combined with exposure datasets of commensurate resolution to calculate current and future flood risk. Our data show that the total US population exposed to serious flooding is 2.6-3.1 times higher than previous estimates, and that nearly 41 million Americans live within the 1% annual exceedance probability floodplain (compared to only 13 million when calculated using FEMA flood maps). We find that population and GDP growth alone are expected to lead to significant future increases in exposure, and this change may be exacerbated in the future by climate change.
过去在美国估算降雨引发洪水风险的尝试，要么覆盖范围不完整，分辨率粗糙，要么使用过于简化的洪水过程模型。在本文中，我们使用了一个新的覆盖美国整个毗连地区的30米分辨率模型，该模型采用二维洪水物理表示法来生成洪水危险估计值，其与利用详细数据构建的局部模型的技能在90%的精度范围内相匹配。这些洪水深度与具有相应分辨率的暴露数据集相结合，以计算当前和未来的洪水风险。我们的数据表明，面临严重洪水的美国总人口比先前估计高出2.6至3.1倍，并且近4100万美国人生活在年超越概率为1%的洪泛区内（相比之下，使用联邦紧急事务管理局洪水地图计算时只有1300万）。我们发现，仅人口和国内生产总值增长预计就会导致未来暴露情况显著增加，而且这种变化在未来可能会因气候变化而加剧。
