What is the difference between NED and CLICK?
The National Elevation Dataset (NED) is a National Map dataset that contains bare-earth raster surfaces, maintained at three resolutions: 1 arc-second (~30m), 1/3 arc-second (~10m), and 1/9 arc-second (~3m). The NED layers are derived from a variety of data sources, including cartographic, photogrammetric, auto-correlated, and lidar. The 1 and 1/3 resolutions provide complete CONUS coverage while the 1/9 layer coverage is being expanded as suitable data becomes available. Data is available through The National Map Seamless Server. The USGS Center for Lidar Information Coordination and Knowledge (CLICK) is a portal for lidar information, discussion, and data. Its primary mission is to support scientific research on lidar point data. Voluntarily contributed lidar point clouds are available for download as tiles. More recent contributions are in LAS format, include all returns, and usually have been classified. Older data are often in ASCII format, may be split into separate files of firs
