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2005 Southwest Florida Water Management District (SWFWMD) LiDAR: Marion County

browse graphicThis kmz file shows the extent of coverage for the 2005 SWFWMD Marion County, FL lidar data set.
Digital terrain models (DTM) provide a 3-dimensional representation of the earth's surface. The DTM for the Southwest Florida Water Management District project was used for orthoimagery rectification and to create a surface from which to interpolate contours. The DTM was derived from LIDAR data points and supplemental 3D breaklines. The files are provided in ESRI generate format (.gen).

Cite this dataset when used as a source.

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    Distribution Formats
    • LAZ
    Distributor DOC/NOAA/NOS/OCM > Office for Coastal Management, National Ocean Service, National Oceanic and Atmospheric Administration, U.S. Department of Commerce
    Point of Contact Southwest Florida Water Management District
    352-796-7211
    data.maps@watermatters.org
    Documentation links not available.
    Originator
    • DOC/NOAA/NOS/OCM > Office for Coastal Management, National Ocean Service, National Oceanic and Atmospheric Administration, U.S. Department of Commerce
    Originator
    • Southwest Florida Water Management District (SWFWMD)
    Publisher
    • DOC/NOAA/NOS/OCM > Office for Coastal Management, National Ocean Service, National Oceanic and Atmospheric Administration, U.S. Department of Commerce
    Date(s)
    • publication: 2013-08-30
    Data Presentation Form: Digital image
    Dataset Progress Status Complete
    Data Update Frequency: As needed
    Purpose: The DTM was developed to support the DISTRICT's regulatory, land management and acquisition, planning, engineering, and habitat restoration projects
    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be aware that temporal changes may have occurred since this data set was collected and some parts of this data may no longer represent actual surface conditions.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: Unknown  to  Unknown
    Spatial Reference System: urn:ogc:def:crs:EPSG::4269 Ellipsoid in Meters
    Spatial Bounding Box Coordinates:
    N: 29.528310
    S: 28.954762
    E: -81.629324
    W: -82.545499
    Spatial Coverage Map:
    Themes
    • Bathymetry/Topography
    • LiDAR LAS digital terrain model
    • LiDAR
    • Terrain
    • Model
    • Elevation
    • Surface
    Places
    • Florida
    • Marion County
    • Southwest Florida Water Management District
    Use Constraints No constraint information available
    Fees Fee information not available.
    Lineage Statement Lineage statement not available.
    Processor
    • Merrick & Company
    • DOC/NOAA/NOS/OCM > Office for Coastal Management, 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
    • LIDAR data was collected using Merrick's ALS40 sensor. The data was field-verified for complete coverage of the project area. Raw data files were parsed into manageable client-specific tiles. These tiles were then processed through automated filtering that separates the data into different classification groups: error points, ground points, and canopy/building points. The data was next taken into a graphic environment to reclassify the erroneous points that may remain in the LIDAR point cloud after auto filter. The surface was then normalized into a digital surface model (DSM). Final data extraction for the client's keypoint (statistically significant points) and canopy-building files were then generated. Using orthophotography, planimetric features were compiled as breaklines to supplement the LIDAR data. The LIDAR digital surface model was then processed with the breaklines, and contour lines were interpolated. The contours were exported from Merrick's MARS software into Microstation. The contour data was checked for spikes and holes. ASCII text files were exported from MicroStation in x,y, z format (.xyz). A custom program is used to reformat these files into ESRI generate format (.gen). A single hard breakline .gen file was produced for the entire project area for linear breaklines. A single hard replace polygon breakline .gen file was also produced for the entire project area. A model key point .gen file was produced for each tile in the project area and includes a 100' buffered area around the tile's extent. LIDAR data was collected using Merrick's ALS40 sensor. The data was field-verified for complete coverage of the project area. Raw data files were parsed into manageable client-specific tiles. These tiles were then processed through automated filtering that separates the data into different classification groups: error points, ground points, and canopy/building points. The data was next taken into a graphic environment to reclassify the erroneous points that may remain in the LIDAR point cloud after auto filter. The surface was then normalized into a digital surface model (DSM). Final data extraction for the client's keypoint (statistically significant points) and canopy-building files were then generated. Using orthophotography, planimetric features were compiled as breaklines to supplement the LIDAR data. The LIDAR digital surface model was then processed with the breaklines, and contour lines were interpolated. The contours were exported from Merrick's MARS software into Microstation. The contour data was checked for spikes and holes. ASCII text files were exported from MicroStation in x,y, z format (.xyz). A custom program is used to reformat these files into ESRI generate format (.gen). A single hard breakline .gen file was produced for the entire project area for linear breaklines. A single hard replace polygon breakline .gen file was also produced for the entire project area. A model key point .gen file was produced for each tile in the project area and includes a 100' buffered area around the tile's extent.
    • The NOAA Coastal Services Center (CSC) received the files in las format. The files contained lidar elevation and intensity measurements. The data were in Florida State Plane West coordinates and NAVD88 (orthometric) heights in feet. CSC performed the following processing for data storage and Digital Coast provisioning purposes: 1. The data were converted from FL State Plane West coordinates to geographic coordinates. 2. The data were converted from NAVD88 (orthometric) heights in feet to GRS80 (ellipsoid) heights in meters using Geoid 03. 3. The LAS data were sorted by latitude and the headers were updated. 4. The data were converted to LAZ format.
    • 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: 2013-10-17

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