Digital Shoreline Analysis System version 4.1 Transects with Short-Term Rate Calculations for the New England South region from Dartmouth, Massachusetts to Napatree Point, Rhode Island (NewEnglandS_ST.shp)

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.

沙质滨海海滩是热门休闲度假胜地，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，滨海开发的热度仍在不断攀升。由此，社会对精准获取历史与当前海岸线变化信息的需求日益高涨。为满足这一国家层面的需求，美国地质调查局（U.S. Geological Survey, USGS）下属的海岸与海洋地质项目组，正通过海岸线变化国家评估项目（National Assessment of Shoreline Change Project），对美国本土及阿拉斯加、夏威夷部分区域的开阔洋面沙质海岸沿线现有可靠历史海岸线数据进行汇编整合。

当前尚无广泛认可的海岸线变化分析标准。现有海岸线数据测量方法与变化速率计算方法因研究而异，导致不同研究的成果无法整合至全州或区域尺度的评估工作中。本次国家评估项目的核心初衷，便是开发一套跨海岸通用的标准化海岸线位置变化测量方法，其目标在于助力实现以内部一致的方式，定期系统性更新海岸线变化评估结果的工作流程。