NSW Foundation Spatial Data Framework - Elevation and Depth - Digital Elevation Model

Digital Elevation Models (DEM) are derived from Spatial Services’ (SS) point cloud data. The DEM is a bare earth representation of the earth’s surface where all the above ground feature has been removed.\r\n\r\nDEM derived from LiDAR: 1m or 2m resolution. Data is not hydrologically enforced (breaklines) or hydrologically conditioned (identification and analysis of sinks).\r\n\r\nDEM derived photogrammetry: data is 5m resolution. Areas of no data caused by steep slopes, shadow and vegetation have been interpolated or filled-in with another data source and will not be as accurate as the bare open ground areas. The data is not hydrologically\r\nenforced (breaklines) or hydrologically conditioned identification and analysis of sinks).

数字高程模型（Digital Elevation Models, DEM）由空间服务公司（Spatial Services, SS）的点云数据生成。该DEM为去除所有地表以上地物后的裸地地表表达。

基于激光雷达（LiDAR）生成的DEM：分辨率为1米或2米。此类数据未开展水文强制校正（含地形断裂线处理）或水文条件优化（包括汇水区识别与分析）。

基于摄影测量生成的DEM：数据分辨率为5米。因陡坡、阴影与植被覆盖产生的无数据区域已通过插值或其他数据源补全，其精度将低于开阔裸地区域。此类数据未开展水文强制校正（含地形断裂线处理）或水文条件优化（包括汇水区识别与分析）。