Sea-level rise represents a severe hazard for populations living within low-elevation coastal zones and is already largely affecting coastal communities worldwide. As sea level continues to rise following unabated greenhouse gas emissions, the exposure of coastal communities to inundation and erosion will increase exponentially. These impacts will be further magnified under extreme storm conditions. In this paper, we focus on one of the most valuable coastal real estate markets globally (Palm Beach, FL). We use XBeach, an open-source hydro and morphodynamic model, to assess the impact of a major tropical cyclone (Hurricane Matthew, 2016) under three different sea-level scenarios. The first scenario (modern sea level) serves as a baseline against which other model runs are evaluated. The other two runs use different 2100 sea-level projections, localized to the study site: (i) IPCC RCP 8.5 (0.83 m by 2100) and (ii) same as (i), but including enhanced Antarctic ice loss (1.62 m by 2100). Our results show that the effective doubling of future sea level under heightened Antarctic ice loss amplifies flow velocity and wave height, leading to a 46% increase in eroded beach volume and the overtopping of coastal protection structures. This further exacerbates the vulnerability of coastal properties on the island, leading to significant increases in parcel inundation.

海平面上升对生活在低海拔沿海地区的人口构成严重危害，并且已经在很大程度上影响了全世界的沿海社区。随着温室气体排放量不断增加，海平面继续上升，沿海社区遭受洪水和侵蚀的风险将成倍增加。在极端风暴条件下，这些影响将进一步放大。在本文中，我们关注全球最有价值的沿海房地产市场之一（佛罗里达州棕榈滩）。我们使用开源水力和形态动力学模型 XBeach 来评估主要热带气旋（马修飓风，2016 年）在三种不同海平面情景下的影响。第一个场景（现代海平面）用作评估其他模型运行的基准。另外两次运行使用不同的 2100 海平面预测，本地化到研究地点：（i）IPCC RCP 8.5（到 2100 年为 0.83 m）和（ii）与（i）相同，但包括增加的南极冰损失（到 2100 年为 1.62 m）。我们的研究结果表明，在南极冰损失加剧的情况下，未来海平面的有效翻倍会放大流速和波高，导致侵蚀的海滩体积增加 46%，并导致沿海保护结构的覆盖。这进一步加剧了岛上沿海财产的脆弱性，导致包裹淹没显着增加。导致被侵蚀的海滩体积增加了 46%，海岸保护结构被淹没。这进一步加剧了岛上沿海财产的脆弱性，导致包裹淹没显着增加。导致被侵蚀的海滩体积增加了 46%，海岸保护结构被淹没。这进一步加剧了岛上沿海财产的脆弱性，导致包裹淹没显着增加。