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2009 USGS New Jersey Lidar: Mercer County

browse graphicThis kmz file shows the extent of coverage for the 2009 USGS Mercer County, NJ lidar data set.
High accuracy LiDAR data covering Mercer County New Jersey (228 sq miles). These datasets will be the initial acquisition to support general geospatial needs of the USGS and the New Jersey Department of Environmental Protection (NJ-DEP).

Cite this dataset when used as a source.

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    Distribution Formats
    • LAZ
    Distributor DOC/NOAA/NOS/CSC > Coastal Services Center, National Ocean Service, National Oceanic and Atmospheric Administration, U.S. Department of Commerce
    Point of Contact Roger Barlow
    U.S. Geological Survey
    703-648-5189
    rbarlow@usgs.gov
    Associated Resources
    • Lidar Survey Report
    Originator
    • DOC/NOAA/NOS/CSC > Coastal Services Center, National Ocean Service, National Oceanic and Atmospheric Administration, U.S. Department of Commerce
    Originator
    • DOI/USGS > United States Geological Survey, U.S. Department of the Interior
    Publisher
    • DOC/NOAA/NOS/CSC > Coastal Services Center, National Ocean Service, National Oceanic and Atmospheric Administration, U.S. Department of Commerce
    Date(s)
    • publication: unknown
    Data Presentation Form: Digital image
    Dataset Progress Status Complete
    Data Update Frequency: Not planned
    Supplemental Information: - Technical Acquisition Parameters: Utilizing Leica ALS50 II laser systems which can collect data at laser pulse rates up to 150 KHz, Photo Science flew the project area at 7,000 feet AGL and utilized a 19 degree full-angle field of view. Flights were accomplished nominally at 98 knots (ground speed) with a pulse rate of 113,600Hz, collecting four returns per pulse. The scan rate was be set at 50.4Hz. These settings resulted in a swath of 2,343 feet with maximum along track and cross track spacing of 3.28 feet (1.0 meters). - Environmental Acquisition Conditions: Leaf-Off, snow free, non-flood conditions. - Nominal Pulse density: Average point density is 3.15 points per sq. Meter Average point spacing is 0.56 meters. - Calibration procedures: Photo Science has created a significant boresight facility at the Frankfort, KY airport where the Lidar platforms are stationed when not in service. Boresighting at this facility takes place with our Lidar sensors at numerous times throughout the year. Additionally, a mini-calibration site was established at the Robbinsville Airport at the project site. Additional calibration flights were conducted over this site to ensure accurate determination of the calibration parameters throughout the times of acquisition. - GPS: Acquisition for this project was completed using the base station from the NGS database selected near the center of the acquisition area to serve as control for all lifts. A ground based GPS receiver was occupied at the station during all aerial collection. The published NGS positions of the base station and raw GPS observation data were used in the kinematic GPS post-processing of all lifts to provide positioning for the point clouds produced for this project. - Maximum and mean differential baseline lengths: Nominal Maximum base line distance was approximately 20 Miles Mean base line distance was approximately 11 Miles - Geoid Model Used: Geoid 03 was used for all height conversion from ellipsoidal to orthometric heights. - Reference System: Horizontal: New Jersey State Plane Coordinate System, 1983 North American Datum, feet Vertical: North American Vertical Datum of 1988 (NAVD88), feet.
    Purpose: The purpose of the Mercer County Lidar project is to provide LiDAR data for New Jersey Department of Environmental Protection (NJ-DEP). This project acquired and produced high accuracy bare-earth processed LiDAR data in LAS format and 1.0-meter Digital Elevation Models (DEMs) in ArcGrid format for approximately 228 square miles of Mercer County.
    Use Limitations
    • These data depict the elevations at the time of the survey and are only accurate for that time. Users should be aware that temporal changes may have occurred since this data set was collected and some parts of this data may no longer represent actual surface conditions. Users should not use this data for critical applications without a full awareness of its limitations. Any conclusions drawn from analysis of this information are not the responsibility of NOAA or any of its partners. These data are NOT to be used for navigational purposes.
    Time Period: 2009-03-31  to  2009-04-25
    Spatial Reference System: urn:ogc:def:crs:EPSG::4269 Ellipsoid in Meters
    Spatial Bounding Box Coordinates:
    N: 40.425498
    S: 40.126421
    E: -74.471774
    W: -74.956084
    Spatial Coverage Map:
    Themes
    • Bathymetry/Topography
    • DEM
    • LiDAR
    • laser
    • digital elevation model
    • elevation
    Places
    • US
    • New Jersey
    • Mercer County
    Use Constraints No constraint information available
    Fees Fee information not available.
    Lineage Statement Lineage statement not available.
    Processor
    • Photo Science
    • DOC/NOAA/NOS/CSC > Coastal Services Center, National Ocean Service, National Oceanic and Atmospheric Administration, U.S. Department of Commerce
    • DOC/NOAA/NESDIS/NGDC > National Geophysical Data Center, NESDIS, NOAA, U.S. Department of Commerce
    Processing Steps
    • Leica software was used in the post processing of the airborne GPS and inertial data that is critical to the positioning of the sensor during all flights. This software suite includes Applanix's PosPac and Waypoint's GrafNav solutions. PosPac provides the smoothed best estimate of trajectory (SBET) that is necessary for Leica's post processor to develop the point cloud from the LiDAR missions. The point cloud is the mathematical three dimensional collection of all returns from all laser pulses as determined from the aerial mission. At this point this data is ready for analysis, classification, and filtering to generate a bare earth surface model in which the above ground features are removed from the data set. The point cloud was manipulated within the Leica software; GeoCue, TerraScan, and TerraModeler software was used for the automated data classification, manual cleanup, and bare earth generation from this data. Project specific macros were used to classify the ground and to remove the side overlap between parallel flight lines. All data was manually reviewed and any remaining artifacts removed using functionality provided by TerraScan and TerraModeler. The project was tiled adhering to the State of New Jersey 5000'x5000' tile schema and each tile was saved in LAS format 1.1 including GPS time. The data was classified as follows: Class 1 - Unclassified/Extracted Features; Class 2 - Bare Earth Ground; Class 9 - water; Class 12 - overlap.
    • A Terrascan macro was used to classify the Lidar points inside rivers and lakes from class 2 to class 9. This classification was visually inspected by comparing the bare earth class against the hydro breaklines.
    • The NOAA Coastal Services Center (CSC) received the files in las format. The files contained Lidar elevation and intensity measurements. The data were in projected in New Jersey State Plane (NAD83) coordinates, and referenced to the orthometric datum of NAVD88 utilizing Geoid 03. CSC performed the following processing to the data to make it available within the Digital Coast: 1. The data were converted from New Jersey State Plane ned(NAD83) coordinates to geographic coordinates (NAD83). 2. The data were converted from NAVD88 (orthometric) heights to GRS80 (ellipsoid) heights using Geoid 03. 3. The LAS data were sorted by latitude and the headers were updated.
    • The NOAA National Geophysical Data Center (NGDC) received lidar data files via ftp transfer from the NOAA Coastal Services Center. The data are currently being served via NOAA CSC Digital Coast at http://www.csc.noaa.gov/digitalcoast/. The data can be used to re-populate the system. The data are archived in LAS or LAZ format. The LAS format is an industry standard for LiDAR data developed by the American Society of Photogrammetry and Remote Sensing (ASPRS); LAZ is a loseless compressed version of LAS developed by Martin Isenburg (http://www.laszip.org/). The data are exclusively in geographic coordinates (either NAD83 or ITRF94). The data are referenced vertically to the ellipsoid (either GRS80 or ITRF94), allowing for the ability to apply the most up to date geoid model when transforming to orthometric heights.

    Metadata Last Modified: 2013-06-04

    For questions about the information on this page, please email: mike.sutherland@noaa.gov