Downloading Lidar Data When downloading a lidar data set, users will find that each directory contains the LAZ files for the data set, a shapefile providing the tile scheme (zipped as tileindex.zip), and a metadata record (nj2010_arra_3counties_metadata.xml). File nj2010_arra_3counties_minmax.csv contains the xyz ranges for each LAZ file. LAZ files are a compressed version of the standard LAS files (format available at http://asprs.org/Committee-General/LASer-LAS-File-Format-Exchange-Activities.html) and can be uncompressed using the free LASzip software available at www.laszip.org. Directories may contain over a thousand files, so users will generally want a mechanism that allows downloading in bulk. One option is to use Wget (freely available at http://www.gnu.org/software/wget/), a command line utility that is very flexible and works on multiple platforms. An example usage of Wget is given below. Other options are available, and a Web search for "download manager" should provide some useful results. The data are all in geographic coordinates using the North American Datum of 1983 (NAD83). The version of the NAD83 datum may vary slightly, but all are one of the updated realizations such as the High Accuracy Reference Network (HARN), Continuously Operating Reference System of 1996 (CORS96), or National Spatial Reference System of 2007 (NSRS2007), and not the original NAD83(86). This may not be evident in the metadata. Vertical units are meters and all have been converted from NAD83 ellipsoid heights to orthometric North American Vertical Datum (NAVD) of 1988 heights using GEOID18. If you would rather get a subset of the data instead of the full dataset or need custom processing, you can do so through the Digital Coast Data Access Viewer (https://www.coast.noaa.gov/dataviewer/#/lidar/search/where:ID=4868). Example using WGET To download all the .laz files in https://coast.noaa.gov/htdata/lidar1_z/geoid18/data/4868, execute the following wget command in a command or terminal window: wget -nd -r -A.laz https://coast.noaa.gov/htdata/lidar1_z/geoid18/data/4868 For More Information NOAA Office for Coastal Management (843) 740-1200 coastal.info@noaa.gov