Topobathymetric Lidar Survey of Breton and Gosier Islands, Louisiana, January 16 and 18, 2014

This dataset contains binary point-cloud data and a Digital Elevation Model (DEM), produced from remotely sensed, geographically referenced topobathymetric measurements encompassing the Breton Island and Gosier Islands, LA study area. The original area of interest was buffered by 100 meters to ensure complete coverage, resulting in approximately 75 square miles of lidar data. The Breton Island Lidar project called for the planning, acquisition, processing, and derivative products of topobathymetric lidar data, collected at a nominal pulse spacing (NPS) of 0.5-0.45 meters (4-5 points/square meter). Lidar acquisition was prioritized to coincide with the lowest tide possible. Water clarity was also assessed and deemed acceptable prior to acquisition flights. The data, in meters, are projected to UTM Zone 16 North and referenced horizontally to the NAD83 (2011) datum and vertically to the NAVD88 (GEOID12A) datum. The classified point-cloud data were delivered in LAS v1.2 format and the merged DEM was converted to a GeoTIFF file. Each LAS file contains data in a 1-kilometer by 1-kilometer tile named according to the US National Grid conventions. The final product was a DEM for Breton Island along with a LAZ file for both Breton Island and Gosier Islands. For further information regarding data collection and/or processing methods refer to USGS Open-File Report Analysis of Shoreline and Geomorphic Change for Breton Island, Louisiana from 1869 to 2014 (https://doi.org/10.3133/ofr20161039).

本数据集包含二进制点云数据与数字高程模型（Digital Elevation Model, DEM），其数据源自覆盖美国路易斯安那州布雷顿岛（Breton Island）与戈西尔群岛（Gosier Islands）研究区域的遥感地理参考地形测深测量成果。为确保完整覆盖研究区域，原始感兴趣范围向外缓冲100米，最终得到约75平方英里的激光雷达（Light Detection and Ranging, LiDAR）数据。布雷顿岛激光雷达项目需完成地形测深激光雷达数据的规划、采集、处理及其衍生产品制作，采集时的标称脉冲间距（Nominal Pulse Spacing, NPS）为0.5~0.45米（即每平方米4~5个点）。激光雷达采集工作优先安排在最低潮时段进行，且在飞行采集前对水体透明度进行了评估，确认符合采集要求。该数据以米为单位，投影采用通用横轴墨卡托（Universal Transverse Mercator, UTM）16北带，水平基准为NAD83（2011），垂直基准为NAVD88（GEOID12A）。分类后的点云数据以LAS v1.2格式交付，合并后的DEM文件转换为GeoTIFF格式。每个LAS文件包含1千米×1千米的分幅数据，文件名遵循美国国家网格命名规范。最终产品包含布雷顿岛专用DEM，以及覆盖布雷顿岛与戈西尔群岛的LAZ文件。如需了解更多数据采集与处理方法的相关信息，请参考美国地质调查局（United States Geological Survey, USGS）公开文件报告《路易斯安那州布雷顿岛1869—2014年海岸线与地貌变化分析》（https://doi.org/10.3133/ofr20161039）。