Offshore baseline for the southern North Carolina (NCsouth) coastal region generated to calculate shoreline change rates

Sandy ocean beaches are a popular recreational destination, often surrounded by communities containing valuable real estate. Development is on the rise despite the fact that coastal infrastructure is subjected to flooding and erosion. As a result, there is an increased demand for accurate information regarding past and present shoreline changes. To meet these national needs, the Coastal and Marine Geology Program of the U.S. Geological Survey (USGS) is compiling existing reliable historical shoreline data along open-ocean sandy shores of the conterminous United States and parts of Alaska and Hawaii under the National Assessment of Shoreline Change project.
There is no widely accepted standard for analyzing shoreline change. Existing shoreline data measurements and rate calculation methods vary from study to study and prevent combining results into state-wide or regional assessments. The impetus behind the National Assessment project was to develop a standardized method of measuring changes in shoreline position that is consistent from coast to coast. The goal was to facilitate the process of periodically and systematically updating the results in an internally consistent manner.

沙质滨海沙滩是广受青睐的休闲度假目的地，周边往往分布着坐拥高价值不动产的社区。尽管沿海基础设施持续面临洪涝与侵蚀威胁，滨海开发规模仍呈上升态势。因此，精准掌握海岸历史与当前岸线变化情况的需求日益攀升。为满足国家层面的相关需求，美国地质调查局（U.S. Geological Survey, USGS）下属海岸与海洋地质项目组正依托《海岸变化国家评估》（National Assessment of Shoreline Change）项目，对美国本土、阿拉斯加部分区域及夏威夷的开阔洋域沙质海岸的现有可靠历史岸线数据进行汇编整合。
当前学界尚未形成一套广泛认可的岸线变化分析标准。现有岸线数据测量方法与岸线变化速率计算方案因研究而异，导致相关成果难以整合至州级或区域尺度的评估工作中。开展本次《海岸变化国家评估》（National Assessment of Shoreline Change）项目的核心动因，便是研发一套跨海岸统一的标准化岸线位置变化测量方法。项目目标在于推动岸线变化评估结果实现定期、系统的更新，并确保更新过程具备内在一致性。