Topobathymetric Model of the Strait of Juan de Fuca, 1891 to 2016

To support the modeling of storm-induced flooding, the U.S. Geological Survey (USGS) Coastal National Elevation Database (CoNED) Applications Project has created an integrated 1-meter topobathymetric digital elevation model (TBDEM) for the Strait of Juan de Fuca, which is located at the outlet of the Salish Sea. The international boundary between Canada and the northwestern part of the United States bisects the strait. High-resolution coastal topobathymetric data is required to identify flooding, storms, and sea-level rise inundation hazard zones and other earth science applications, such as the development of sediment transport and storm surge models. The new TBDEM consists of the best available multi-source topographic and bathymetric elevation data for the Strait of Juan de Fuca including neighboring islands, canals, and inlets. The Strait of Juan de Fuca TBDEM integrates 11 different data sources including topographic and bathymetric data, such as lidar point clouds and multi-beam acoustic surveys obtained from USGS, the National Oceanic and Atmospheric Administration, the U.S. Army Corps of Engineers, the Puget Sound Lidar Consortium, and the Washington Department of Natural Resources. The topographic and bathymetric surveys were sorted and prioritized based on survey date, accuracy, spatial distribution, and point density to develop a model based on the best available elevation and bathymetric data. Because bathymetric data are typically referenced to tidal datums, such as Mean High Water or Mean Low Water, all tidally-referenced heights were transformed into orthometric heights based on the GEOID12B datum, which is normally used for mapping elevation on land using the North American Vertical Datum of 1988. The spatial horizontal resolution is 1-meter with the general location ranging from Victoria, British Columbia in the north to Port Angeles, Washington in the south and extending to a depth of 365 meters. The overall temporal range of the input topography and bathymetry is 1891 to 2016. The topography surveys are from 2005-2016. The bathymetry surveys were acquired between 1891 and 2015.

为支撑风暴诱发洪水的建模研究，美国地质调查局（U.S. Geological Survey, USGS）海岸国家高程数据库（Coastal National Elevation Database, CoNED）应用项目，针对地处萨利希海出海口的胡安·德富卡海峡（Strait of Juan de Fuca）构建了一套一体化1米分辨率地形水深数字高程模型（topobathymetric digital elevation model, TBDEM）。加拿大与美国西北部的国际国境线横穿该海峡，将其一分为二。高分辨率海岸地形水深数据可用于识别洪水、风暴及海平面上升淹没灾害带，亦可应用于泥沙输运、风暴潮模型开发等多项地球科学研究场景。这套全新的TBDEM整合了胡安·德富卡海峡（含邻近岛屿、航道与海湾）现有最优的多源地形与水深高程数据。胡安·德富卡海峡TBDEM整合了11种不同数据源的地形与水深数据，包括美国地质调查局、美国国家海洋和大气管理局、美国陆军工程兵团、普吉特湾激光雷达（lidar）联盟以及华盛顿州自然资源部提供的激光雷达点云和多波束声学测量数据等。研究人员依据测量日期、精度、空间分布与点云密度对各类地形与水深测量数据进行排序与优先级划分，基于现有最优高程与水深数据构建了该模型。由于水深数据通常参考平均高潮位、平均低潮位等潮汐基准面，所有潮汐参考高程均被转换为基于GEOID12B基准面的正高系统，该基准面与采用1988北美垂直基准面的陆地高程制图标准一致。该模型空间水平分辨率为1米，覆盖范围北至不列颠哥伦比亚省维多利亚市，南至华盛顿州安吉利斯港，最大探测水深达365米。输入的地形与水深数据的时间跨度为1891年至2016年，其中地形测量数据采集于2005年至2016年，水深测量数据的采集时间为1891年至2015年。