Digital Shoreline Analysis System (DSAS) version 4.3 transects with end-point rate calculations for exposed shorelines between the Colville River Delta and Point Barrow for the time period 1947 to 2005

The Arctic Coastal Plain of northern Alaska is an area of strategic economic importance to the United States, is home to remote Native American communities, and encompasses unique habitats of global significance. Coastal erosion along the north coast of Alaska is chronic, widespread, may be accelerating, and is threatening defense and energy-related infrastructure, natural shoreline habitats, and Native communities. There is an increased demand for accurate information regarding past and present shoreline changes across the United States. 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 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.

阿拉斯加北部北极滨海平原（Arctic Coastal Plain）对美国具有重要战略经济价值，是偏远美洲原住民社群的聚居地，同时拥有兼具全球重要性的独特生境。阿拉斯加北海岸的海岸侵蚀长期持续、分布广泛，且或呈加速态势，正威胁着国防与能源相关基础设施、自然岸线生境以及原住民社群。当前，美国国内对获取过往与当前岸线变化精准信息的需求日益增长。为满足此类国家层面的需求，美国地质调查局（U.S. Geological Survey, USGS）下属的海岸与海洋地质项目（Coastal and Marine Geology Program）正依托“全国岸线变化评估”（National Assessment of Shoreline Change）项目，整合美国本土以及阿拉斯加部分区域与夏威夷的沙质海岸沿线现有可靠历史岸线数据。
目前尚未形成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法因研究而异，导致无法将各研究结果整合至全州或区域尺度的评估工作中。本全国岸线变化评估项目的发起动因，正是开发一套跨各海岸统一的岸线位置变化标准化测量方法，其目标是以内部统一的方式，定期且系统地更新岸线变化评估结果，为该更新流程的规范化开展提供便利。