MarthasVineyard_transects_rates_STepr.shp - Digital Shoreline Analysis System version 4.3 transects and short-term (1970-2009) end point shoreline change statistics within the Martha's Vineyard coastal region including the Vineyard Sound-, Nantucket Sound- and Atlantic Ocean- facing coasts of Marth

Due to continued coastal population growth and increased threats of erosion, current data on trends and rates of shoreline movement are required to inform shoreline and floodplain management. The Massachusetts Office of Coastal Zone Management launched the Shoreline Change Project in 1989 to identify erosion-prone areas of the coast. In 2001, a 1994 shoreline was added to calculate both long- and short-term shoreline change rates at 40-meter intervals along ocean-facing sections of the Massachusetts coast.

The Coastal and Marine Geology Program of the U.S. Geological Survey (USGS) in cooperation with the Massachusetts Office of Coastal Zone Management, has compiled reliable historical shoreline data along open-facing sections of the Massachusetts coast under the Massachusetts Shoreline Change Mapping and Analysis Project 2013 Update. Two oceanfront shorelines for Massachusetts (approximately 1,800 km) were (1) delineated using 2008/09 color aerial orthoimagery, and (2) extracted from topographic LIDAR datasets (2007) obtained from NOAA's Ocean Service, Coastal Services Center. The new shorelines were integrated with existing Massachusetts Office of Coastal Zone Management and USGS historical shoreline data in order to compute long- and short-term rates using the latest version of the Digital Shoreline Analysis System (DSAS).

受沿海人口持续增长与海岸侵蚀威胁加剧的双重影响，当前亟需获取海岸线变迁趋势与速率的相关数据，以支撑海岸线与洪泛区的管理决策。马萨诸塞州海岸带管理局（Massachusetts Office of Coastal Zone Management）于1989年启动海岸线变化项目（Shoreline Change Project），旨在识别海岸易侵蚀区域。2001年，研究团队新增1994年海岸线数据集，用于以40米为间隔，计算马萨诸塞州面向海洋的海岸段的长期与短期海岸线变化速率。

美国地质调查局（U.S. Geological Survey, USGS）海岸与海洋地质项目组与马萨诸塞州海岸带管理局合作，依托《马萨诸塞州海岸线变化制图与分析项目2013更新版》（Massachusetts Shoreline Change Mapping and Analysis Project 2013 Update），完成了马萨诸塞州面向开阔海域海岸段的可靠历史海岸线数据整编工作。本次研究共生成两条马萨诸塞州滨海海岸线（全长约1800千米）：其一通过2008/2009年彩色航空正射影像（color aerial orthoimagery）勾勒得到，其二从美国国家海洋和大气管理局（National Oceanic and Atmospheric Administration, NOAA）海洋服务局海岸服务中心获取的2007年地形激光雷达（LIDAR）数据集中提取得到。研究团队将新绘制的海岸线数据与现有马萨诸塞州海岸带管理局及美国地质调查局的历史海岸线数据进行整合，以采用最新版数字海岸线分析系统（Digital Shoreline Analysis System, DSAS）计算海岸线长期与短期变化速率。