U.S. Geological Survey 2014 first vector digital data U.S. Geological Survey Data Series 767 St. Petersburg, FL U.S. Geological Survey http://pubs.er.usgs.gov/publication/ds767 ASCII xyz point cloud data were produced from remotely sensed, geographically referenced elevation measurements by the U.S. Geological Survey (USGS). Elevation measurements were collected over the area using the second-generation Experimental Advanced Airborne Research Lidar (EAARL-B), a pulsed laser ranging system mounted onboard an aircraft to measure ground elevation, vegetation canopy, and coastal topography. The system uses high-frequency laser beams directed at the Earth's surface through an opening in the bottom of the aircraft's fuselage. The laser system records the time difference between emission of the laser beam and the reception of the reflected laser signal in the aircraft. The plane travels over the target area at approximately 55 meters per second at an elevation of approximately 300 meters, resulting in a laser swath of approximately 240 meters with an average point spacing of 0.5 - 1.6 meters. A bias correction of -16 centimeters was applied as a result of instrument calibrations, yielding a nominal vertical elevation accuracy expressed as the root mean square error (RMSE) of 20 centimeters. A peak sampling rate of 15 - 30 kilohertz results in an extremely dense spatial elevation dataset. Over 100 kilometers of coastline can be surveyed easily within a 3- to 4-hour mission. When resultant elevation maps for an area are analyzed, they provide a useful tool to make management decisions regarding land development. The purpose of this project was to produce highly detailed and accurate digital elevation maps of a portion of the New Jersey coastline, pre-Hurricane Sandy (October 2012 hurricane), for use as a management tool and to make these data available to natural-resource managers and research scientists. Raw lidar data are not in a format that is generally usable by resource managers and scientists for scientific analysis. Converting dense lidar elevation data into a readily usable format without loss of essential information requires specialized processing. The U.S. Geological Survey's Coastal and Marine Geology Program (CMGP) has developed custom software to convert raw lidar data into a GIS-compatible map product to be provided to GIS specialists, managers, and scientists. The primary tool used in the conversion process is Airborne Lidar Processing System (ALPS), a multi-tiered processing system developed originally by a USGS-NASA collaborative project. Specialized processing algorithms are used to convert raw waveform lidar data acquired by the EAARL-B to georeferenced spot (x,y,z) returns for "first surface" and "bare earth" topography. The terms first surface and bare earth refer to the digital elevation data of the terrain, but while first-surface data include vegetation, buildings, and other manmade structures, bare-earth data do not. The zero crossing of the second derivative (that is, detection of stationary points) is used to detect the first return, resulting in "first surface" topography, while the trailing edge algorithm (that is, the algorithm searches for the location prior to the last return where direction changes along the trailing edge) is used to detect the range to the last return, or "bare earth" (the first and last returns being the first and last significant measurable portion of the return pulse). Statistical filtering, known as the Random Consensus Filter (RCF), is used to remove false bottom returns and other outliers from the EAARL-B topography data. The filter uses a grid of non-overlapping square cells (buffer) of user-defined size overlaid onto the original point cloud. The user also defines the vertical tolerance (vertical width) based on the topographic complexity and point-sampling density of the data. The maximum allowable elevation range within a cell is established by this vertical tolerance. An iterative process searches for the maximum concentration of points within the vertical tolerance and removes those points outside of the tolerance (Nayegandhi and others, 2009). These data are then converted to the North American Datum of 1983 and the North American Vertical Datum of 1988 (using the GEOID12A model). Each file contains data located in a 10-kilometer by 10-kilometer tile, where the upper-left bound can be ascertained quickly through the filename. The first 3 numbers in the filename represent the left-most UTM easting coordinate (e###000) in meters, the next 4 numbers represent the top-most UTM northing coordinate (n####000) in meters, and the last 2 numbers (##) represent the UTM zone in which the tile is located (for example, fs_e123_n4567_18). The development of custom software for creating these data products has been supported by the U.S. Geological Survey CMGP's Lidar for Science and Resource Management project. Processed data products are used by the U.S. Geological Survey CMGP's National Assessments of Coastal Change Hazards project to quantify the vulnerability of shorelines to coastal change hazards such as severe storms, sea-level rise, and shoreline erosion and retreat. 20121026 ground condition Complete None planned ISO 19115 Topic Category elevation General Airborne Lidar Processing System ALPS Cessna 310 Digital Elevation Model DEM EAARL-B Experimental Advanced Airborne Research Lidar laser altimetry lidar remote sensing topography Global Change Master Science Directory LAND SURFACE > TOPOGRAPHY > TERRAIN ELEVATION Global Change Master Science Directory LAND SURFACE > TOPOGRAPHY > TERRAIN ELEVATION OCEAN > COASTAL PROCESSES > BARRIER ISLANDS OCEAN > COASTAL PROCESSES > BEACHES OCEAN > COASTAL PROCESSES > SHORELINE DISPLACEMENT DOI/USGS/CMG > COASTAL AND MARINE GEOLOGY, U.S. GEOLOGICAL SURVEY, U.S. DEPARTMENT OF INTERIOR GCMD Instrument LIDAR > LIGHT DETECTION AND RANGING Geographic Names Information System Atlantic Cape May Monmouth Ocean New Jersey Atlantic Ocean General First Surface General 2012 Pre-Hurricane Sandy None The U.S. Geological Survey requests to be acknowledged as originators of these data in future products or derivative research. Xan Fredericks Cherokee Nation Technology Solutions, U.S. Geological Survey, St. Petersburg Coastal and Marine Science Center, St. Petersburg, FL Lidar Validation and Processing Analyst mailing and physical address

600 4th Street South

St. Petersburg FL 33701 USA 727 502-8086 727 502-8182 afredericks@usgs.gov M-F, 8:00-4:00 ET Acknowledgment of the U.S. Geological Survey, St. Petersburg Coastal and Marine Science Center, as a data source would be appreciated in products developed from these data, and such acknowledgment as is standard for citation and legal practices for data source is expected. Sharing of new data layers developed directly from these data would also be appreciated by the U.S. Geological Survey staff. Users should be aware that comparisons with other datasets for the same area from other time periods may be inaccurate due to inconsistencies resulting from changes in photointerpretation, mapping conventions, and digital processes over time. These data are not legal documents and are not to be used as such. Unclassified Unclassified None Microsoft Windows 7 Enterprise Service Pack 1; Esri ArcCatalog 10.1.1.3143 5.3000 E+5 5.4000 E+5 4.35000 E+6 4.34000 E+6 -74.6525237715455 -74.5361080905839 39.2988605229803 39.2083495204455 Nayegandhi, A., Brock, J.C., and Wright, C.W. 2009 International Journal of Remote Sensing 30(4), p. 861-878 The expected accuracy of the measured variables is as follows: attitude within 0.05 degree, 3 centimeters nominal ranging accuracy, and vertical elevation accuracy of 20 centimeters RMSE for the topographic surface. Quality checks are built into the data-processing software. Each file contains data located in a 10-kilometer by 10-kilometer tile where the upper-left bound can be ascertained quickly through the filename. The first 3 numbers in the filename represent the left-most UTM easting coordinate (e###000) in meters, the next 4 numbers represent the top-most UTM northing coordinate (n####000) in meters, and the last 2 numbers (##) represent the UTM zone in which the tile is located (for example, fs_e123_n4567_18). These point-cloud data may appear sparse or nonexistent, which is a result of removal from manual editing or lack of survey coverage. Raw elevation measurements have been determined to be within 1 meter in horizontal accuracy. Typical vertical elevation accuracies for these data are consistent with the point elevation data; however, a ground-control survey is not conducted simultaneously with every lidar survey. Vertical accuracies may vary based on the type of terrain and the accuracy of the GPS and aircraft-attitude measurements. The data were collected using a Cessna 310 aircraft. The EAARL-B laser scanner collects the data using a green-wavelength (532-nanometer) raster scanning laser, while a digital camera acquires a visual record of the flight. The data are stored on hard drives and archived at the U.S. Geological Survey office in St. Petersburg, Florida. The navigational data are processed and then, along with the raw data, are downloaded into ALPS, or the Airborne Lidar Processing System (20130522 - 20131024). Data are converted from units of time to x,y,z points for elevation. 20121026 through 20131024 Xan Fredericks Cherokee Nation Technology Solutions, U.S. Geological Survey, St. Petersburg Coastal and Marine Science Center, St. Petersburg, FL Lidar Validation and Processing Analyst mailing and physical address

600 4th Street South

St. Petersburg FL 33701 USA 727 502-8086 afredericks@usgs.gov M-F, 8:00-4:00 ET A bias correction of -16 centimeters (value determined from instrument calibrations) was applied to the point-cloud data using ALPS (20140811) to account for a change in configuration parameters. Data are formatted into .las and .xyz files, and the derived surface data are converted into raster data (GeoTIFFs). 20140811 Christine Kranenburg Cherokee Nation Technology Solutions, U.S. Geological Survey, St. Petersburg Coastal and Marine Science Center, St. Petersburg, FL Programmer/Analyst mailing and physical address

600 4th Street South

St. Petersburg FL 33701 USA 727 502-8129 ckranenburg@usgs.gov M-F, 7:30-3:30 ET Metadata imported into ArcCatalog 10.1.1.3143 from XML file. 20140814 Xan Fredericks Cherokee Nation Technology Solutions, U.S. Geological Survey, St. Petersburg Coastal and Marine Science Center, St. Petersburg, FL Lidar Validation and Processing Analyst mailing and physical address

600 4th Street South

St. Petersburg FL 33701 USA 727 502-8086 M-F, 8:00-4:00 ET afredericks@usgs.gov Point row and column 1.000000 1.000000 meters Universal Transverse Mercator 18 0.999600 -75.000000 0.000000 500000.000000 0.000000 North American Datum of 1983 Geodetic Reference System 80 6378137.000000 298.25722210100002 North American Vertical Datum of 1988 0.20 meters Explicit elevation coordinate included with horizontal coordinates The input parameters for the random consensus filter (RCF) were: grid cell size (buffer) = 600 centimeters x 600 centimeters; vertical tolerance (vertical width) = 520 centimeters. https://pubs.usgs.gov/of/2009/1078/ *.xyz The "*" represents the file name. The file is .xyz ASCII space-delimited. Internally devised to maintain naming consistency. X UTM easting in meters NAD 83 varying value range Y UTM northing in meters NAD 83 varying value range Z Altitude in meters NAVD 88 varying value range U.S. Geological Survey Xan Fredericks Lidar Validation and Processing Analyst mailing and physical address

600 4th Street South

St. Petersburg FL 33701 USA 727 502-8086 M-F, 8:00-4:00 ET DS 767 Although these data have been processed successfully on a computer system at the U.S. Geological Survey (USGS), no warranty expressed or implied is made regarding the display or utility of the data on any other system, or for general or scientific purposes, nor shall the act of distribution constitute any such warranty. The USGS shall not be held liable for improper or incorrect use of the data describe and/or contained herein. Any use of trade, firm, or product names is for descriptive purposes only and does not imply endorsement by the U.S. Government. ASCII XYZ 1 http://pubs.er.usgs.gov/publication/ds767 None Contact U.S. Geological Survey. Vary Contact U.S. Geological Survey for details. 20121026 20140814 Xan Fredericks Cherokee Nation Technology Solutions, U.S. Geological Survey, St. Petersburg Coastal and Marine Science Center, St. Petersburg, FL Lidar Validation and Processing Analyst mailing and physical address

600 4th Street South

St. Petersburg FL 33701 USA 727 502-8086 M-F, 8:00-4:00 ET afredericks@usgs.gov FGDC Content Standards for Digital Geospatial Metadata FGDC-STD-001-1998 local time http://www.esri.com/metadata/esriprof80.html Esri Metadata Profile