Coastal urban infrastructure and water management programs are vulnerable to the impacts of long-term hydroclimatic changes and to the flooding and physical destruction of disruptive hurricanes and storm surge. Water resilience or, inversely, vulnerability depends on design specifications of the storm and inundation, against which water infrastructure and environmental assets are planned and operated. These design attributes are commonly derived from statistical modeling of historical measurements. Here we argue for the need to carefully examine the approach and associated design vulnerability in coastal areas because of the future hydroclimatic changes and large variability at local coastal watersheds. This study first shows significant spatiotemporal variations of design storm in the Chesapeake Bay of the eastern U.S. Atlantic coast, where the low-frequency high-intensity precipitations vary differently to the tropical cyclones and local orographic effects. Average and gust wind speed exhibited much greater spatial but far less temporal variability than the precipitation. It is noteworthy that these local variabilities are not fully described by the regional gridded precipitation used in CMIP5 climate downscaling and by NOAA's regional design guide Atlas-14. Up to 46.4% error in the gridded precipitation for the calibration period 1950-1999 is further exacerbated in the future design values by the ensemble of 132 CMIP5 projections. The total model projection error (δM) up to -61.8% primarily comes from the precipitation regionalization (δ1), climate downscaling (δ2), and a fraction from empirical data modeling (δE). Thus, a post-bias correction technique is necessary. The bias-corrected design wind speed for 10-yr to 30-yr storms has small changes <20% by the year 2100, but contains large spatial variations even for stations of close proximity. Bias-corrected design precipitations are characteristic of large spatial variability and a notable increase of 2-5 year precipitation in the future along western shores of the Lower and Middle Chesapeake Bay. All these accounts point to the potential vulnerability of water infrastructure and water program in coastal areas, when the hydrological design basis using regional values fails to account for significant spatiotemporal precipitation variations in local coastal watersheds.

中文翻译：

---

在不断变化的沿海环境中评估和管理设计风暴的可变性和投影不确定性。

沿海城市基础设施和水管理计划容易受到长期水文气候变化的影响，以及破坏性飓风和风暴潮的洪水和自然破坏。反水能力或反之，脆弱性取决于暴风雨和洪水的设计规范，针对这些规范规划和运营水基础设施和环境资产。这些设计属性通常来自历史测量的统计建模。这里我们认为，由于未来的水文气候变化和当地沿海流域的巨大变化，需要仔细研究沿海地区的方法和相关的设计脆弱性。这项研究首先显示了美国东部大西洋沿岸切萨皮克湾设计风暴的时空变化，低频高强度降水与热带气旋和局部地形的影响有所不同。平均和阵风风速表现出比降水大得多的空间变化，但随时间变化却小得多。值得注意的是，CMIP5气候缩减中使用的区域网格降水和NOAA的区域设计指南Atlas-14并未完全描述这些局部变化。132 CMIP5投影的集合在将来的设计值中进一步加剧了1950-1999年校准期间网格降水的最大46.4％误差。高达-61.8％的总模型投影误差（δM）主要来自降水区域化（δ1），气候尺度缩小（δ2），以及来自经验数据建模（δE）的一小部分。因此，偏置后校正技术是必要的。到2100年，经过10年至30年暴风雨的偏差校正后的设计风速变化很小，不到20％，但是即使对于附近的气象站，空间变化也很大。偏差校正后的设计降水具有较大的空间变异性，未来切萨皮克湾中下游海湾西岸的降水将有2-5年的显着增加。所有这些说明都指出了沿海地区水利基础设施和水计划的潜在脆弱性，因为使用区域价值的水文设计基础无法说明当地沿海流域的重大时空降水变化。偏差校正后的设计降水具有较大的空间变异性，并且未来切萨皮克湾中下游海湾西岸的降水将显着增加2-5年。所有这些说明都指出了沿海地区水利基础设施和水计划的潜在脆弱性，因为使用区域价值的水文设计基础无法说明当地沿海流域的重大时空降水变化。偏差校正后的设计降水具有较大的空间变异性，并且未来切萨皮克湾中下游海湾西岸的降水将显着增加2-5年。所有这些说明都指出了沿海地区水利基础设施和水计划的潜在脆弱性，因为使用区域价值的水文设计基础无法说明当地沿海流域的重大时空降水变化。