Seafloor Elevation Change from 2017 to 2019 at Looe Key, Florida Keys—Impacts from Hurricane Irma

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Frequently anticipated questions:

What does this data set describe?

Title:
Seafloor Elevation Change from 2017 to 2019 at Looe Key, Florida Keys—Impacts from Hurricane Irma
Abstract:
The U.S. Geological Survey (USGS) St. Petersburg Coastal and Marine Science Center conducted research to quantify bathymetric changes at Looe Key Reef, Florida (FL) within a 26.59 square kilometer-area over the reef proper, and surrounding areas. USGS staff used light detection and ranging (lidar) data acquired by the National Oceanic and Atmospheric Administration (NOAA) in 2018 and 2019 (only the data from 2019 were used in analysis) following the passage of Hurricane Irma. An elevation change analysis between the 2017–2018 USGS multibeam data (Fredericks and others, 2019) and the 2019 NOAA lidar data was performed to quantify and map impacts to seafloor elevation and determine elevation and volume change statistics for eleven habitat types found at Looe Key. For more information about the methods used in this study, refer to Yates and others (2024).
Supplemental_Information:
The 2019 lidar data were collected by Quantum Spatial, Inc. (QSI) using three Riegl USA© systems: a Riegl VQ®-880-G+, a Riegl VQ®-880-GII, and a Riegl VQ®-880-GH. The lidar data are an ancillary product of NOAA's Coastal Mapping Program (CMP), created through a wider Integrated Ocean and Coastal Mapping initiative to increase support for multiple uses of the data.
  1. How might this data set be cited?
    Johnson, Selena A., Fehr, Zachery W., and Jenkins, Connor M., 20251117, Seafloor Elevation Change from 2017 to 2019 at Looe Key, Florida Keys—Impacts from Hurricane Irma: U.S. Geological Survey - St. Petersburg Coastal and Marine Science Center, St. Petersburg, Florida.

    This is part of the following larger work.

    Johnson, Selena A., Fehr, Zachery W., and Jenkins, Connor M., 20251117, Seafloor Elevation Change From 2017 to 2019 at Looe Key, Florida Keys—Impacts from Hurricane Irma: U.S. Geological Survey data release doi:10.5066/P16WTP6Y, U.S. Geological Survey - St. Petersburg Coastal and Marine Science Center, St. Petersburg, Florida.

    Online Links:

  2. What geographic area does the data set cover?
    West_Bounding_Coordinate: -81.44310
    East_Bounding_Coordinate: -81.36494
    North_Bounding_Coordinate: 24.59724
    South_Bounding_Coordinate: 24.53637
  3. What does it look like?
  4. Does the data set describe conditions during a particular time period?
    Beginning_Date: 14-Dec-2017
    Ending_Date: 31-Jan-2019
    Currentness_Reference:
    ground condition
  5. What is the general form of this data set?
    Geospatial_Data_Presentation_Form: tabular, vector, and raster digital data
  6. How does the data set represent geographic features?
    1. How are geographic features stored in the data set?
      This is a Vector data set. It contains the following vector data types (SDTS terminology):
      • Entity point (6668365)
    2. What coordinate system is used to represent geographic features?
      Grid_Coordinate_System_Name: Universal Transverse Mercator
      Universal_Transverse_Mercator:
      UTM_Zone_Number: 17
      Transverse_Mercator:
      Scale_Factor_at_Central_Meridian: 0.9996
      Longitude_of_Central_Meridian: -81.0
      Latitude_of_Projection_Origin: 0.0
      False_Easting: 500000.0
      False_Northing: 0.0
      Planar coordinates are encoded using coordinate pair
      Abscissae (x-coordinates) are specified to the nearest 0.6096
      Ordinates (y-coordinates) are specified to the nearest 0.6096
      Planar coordinates are specified in meters
      The horizontal datum used is NAD83_National_Spatial_Reference_System_2011.
      The ellipsoid used is GRS 1980.
      The semi-major axis of the ellipsoid used is 6378137.0.
      The flattening of the ellipsoid used is 1/298.257222101.
  7. How does the data set describe geographic features?
    1719_LKR_IntersectPoints.shp
    Shapefile attribute table of the elevation change points, clipped to the Looe Key study area. (Source: USGS)
    FID
    Internal feature number. (Source: ESRI) Sequential unique whole numbers that are automatically generated.
    Shape*
    Feature geometry. (Source: ESRI) Point
    ELEV2017
    2017 multibeam elevations (in meters) extracted to point locations. (Source: USGS)
    Range of values
    Minimum:-28.7481
    Maximum:-1.10817
    ELEV2019
    2019 lidar elevations (in meters) extracted to point locations. (Source: USGS)
    Range of values
    Minimum:-28.68
    Maximum:-1.02
    Diff_m
    Difference in elevation (ELEV2019 - ELEV2017) at point locations. (Source: USGS)
    Range of values
    Minimum:-4.02007
    Maximum:4.07977
    POINT_X
    NAD83 UTM 17N easting (X) coordinate. (Source: USGS)
    Range of values
    Minimum:455122.5
    Maximum:461130.5
    POINT_Y
    NAD83 UTM 17N northing (Y) coordinate. (Source: USGS)
    Range of values
    Minimum:2713682.5
    Maximum:2715398.5
    Entity_and_Attribute_Overview:
    1719_LKR_habitat_clipped.zip: The detailed attribute descriptions for the habitat designations in the 1719_LKR_habitat_clipped shapefile are provided in the included data dictionary (DataDictionary_HabitatTypes.docx). These metadata are not complete without these files.
    Entity_and_Attribute_Detail_Citation:
    The entity and attribute information were generated by the individual and/or agency identified as the originator of the dataset. Please review the rest of the metadata record for additional details and information.
    Entity_and_Attribute_Overview:
    1719_LKR_Elevation_and_Volume_Statistics.zip: The detailed attribute descriptions for the elevation (1719_LKR_elevationchange.csv) and volume change (1719_LKR_volume.csv) statistics files are provided in the included data dictionaries (DataDictionary_ElevationChange.docx DataDictionary_HabitatTypes.docx, and DataDictionary_VolumeChange.docx). These metadata are not complete without these files.
    Entity_and_Attribute_Detail_Citation:
    The entity and attribute information were generated by the individual and/or agency identified as the originator of the dataset. Please review the rest of the metadata record for additional details and information.
    Entity_and_Attribute_Overview:
    2017_LKR_multibeam_19lidarExtent.tif: 2017 DEM (.tif) clipped to the Looe Key study area. Values range from -1.10817 m to -28.8242 m and is projected to the NAD83 (NSRS2007) UTM 17N coordinate system. The file format is a 32-bit floating point TIFF with 7925 columns and 6723 rows.
    Entity_and_Attribute_Detail_Citation:
    The entity and attribute information were generated by the individual and/or agency identified as the originator of the dataset. Please review the rest of the metadata record for additional details and information.
    Entity_and_Attribute_Overview:
    2019_LKR_lidar _19multibeamExtent.tif: 2019 DEM (.tif) clipped to the Looe Key study area. Values range from -1.102 m to -28.74 m and is projected to the NAD83 (NSRS2007) UTM 17N coordinate system. The file format is a 32-bit floating point TIFF with 7925 columns and 6723 rows.
    Entity_and_Attribute_Detail_Citation:
    The entity and attribute information were generated by the individual and/or agency identified as the originator of the dataset. Please review the rest of the metadata record for additional details and information.

Who produced the data set?

  1. Who are the originators of the data set? (may include formal authors, digital compilers, and editors)
    • Selena A. Johnson
    • Zachery W. Fehr
    • Connor M. Jenkins
  2. Who also contributed to the data set?
  3. To whom should users address questions about the data?
    Selena A. Johnson
    U.S. Geological Survey - St. Petersburg Coastal and Marine Science Center
    Research Physical Scientist
    600 4th Street South
    St. Petersburg, FL

    727-502-8053 (voice)
    selenajohnson@usgs.gov

Why was the data set created?

These data were used to determine seafloor elevation and volume changes from 2017 to 2019 at Looe Key Reef.

How was the data set created?

  1. From what previous works were the data drawn?
    2017–2018 multibeam data (source 1 of 4)
    Fredericks, Joseph J., Reynolds, Billy J., Farmer, Andrew S., Yates, Kimberly K., and Zawada, David G., 20190722, Multibeam Bathymetry Data Collected in December 2017, February and March 2018 at Looe Key, the Florida Keys: U.S. Geological Survey, St. Petersburg, FL.

    Online Links:

    Type_of_Source_Media: Digital data
    Source_Contribution: Source of historical elevation data used in these analyses.
    2019 lidar data (source 2 of 4)
    Survey, National Geodetic, 20201002, 2018-2019 NOAA NGS Topobathy Lidar DEM Hurricane Irma: Miami to Marquesas Keys, FL: National Oceanic and Atmospheric Administration Office for Coastal Management, Charleston, SC.

    Online Links:

    Type_of_Source_Media: Digital data
    Source_Contribution:
    Source of contemporary elevation data in these analyses. Time period provided represents the range of dates that were used in analysis. The entire lidar dataset spans a larger time period.
    SECAT model (source 3 of 4)
    Zieg, Jonathan A., and Zawada, David G., 2021, Seafloor elevation change analysis tool: U.S. Geological Survey, St. Petersburg, FL.

    Online Links:

    Type_of_Source_Media: Digital data
    Source_Contribution:
    Analysis tool used to calculate seafloor elevation and volume change statistics.
    Unified Florida Reef Tract Map Version 2.0 (source 4 of 4)
    Florida Fish and Wildlife Conservation Commission, 20150901, Florida's Unified Reef Map: Fish and Wildlife Research Institute, St. Petersburg, FL.

    Online Links:

    Type_of_Source_Media: Digital data
    Source_Contribution: Source of habitat type designations used for this analysis.
  2. How were the data generated, processed, and modified?
    Date: 2023 (process 1 of 11)
    Step 1: Seafloor elevation and volume change analyses were performed using methods from Yates and others (2017). The original 2017–2018 multibeam data were downloaded from Fredericks and others (2019). Using VDatum v.3.9, the multibeam data were transformed from their native World Geodetic System of 1984 (WGS84) horizontal datum and ellipsoid heights to the North American Datum of 1983 (NAD83 [2011]) horizontal datum and North American Vertical Datum 1988 (NAVD88) vertical datum, applying the GEOID12B model. The transformed XYZ points were loaded into Global Mapper version 18.2 and gridded using the "Create Elevation Grid from 3D Vector/Lidar Data" tool in the Analysis menu. Grid spacing was manually set to 1 m for the X- and Y-axes and the 'Elevation Grid No Data Distance Criteria' was set to 3.0. The resultant 2017_LooeKey_Multibeam_Clip DEM was exported as a Tagged Image File Format (TIFF, .tif) with the following parameters: 32-bit floating point samples, Sample Spacing of 1 m for both X- and Y-axes, Always Generate Square Pixels, LZW Compression, Generate TFW (World) File, and Generate PRJ File. The 2019 lidar data were downloaded from National Geodetic Survey (2020). The data were downloaded with the following parameters: UTM zone: Zone 17 Range 084W-078W; Horizontal Datum: NAD83; Horizontal Units: Meters; Vertical Datum: NAVD88; Vertical Units: Meters; File Format: Tiff 32-bit Float; Bin Method: TIN; Bin Size: 1.0; Bin Units: Meters; Data Classification: Bathymetric Lidar Points; Data Returns: Any Points; Ancillary Data: No Ancillary Data; and Geoid Name: GEOID12B. Using VDatum version 3.9 Data sources used in this process:
    • 2017–2018 multibeam data
    • 2019 lidar data
    Data sources produced in this process:
    • 2017_LooeKey_Multibeam_Clip DEM
    Date: 2023 (process 2 of 11)
    Step 2: Using ArcGIS Pro version 3.4.3, footprints of both the 2017–2018 multibeam data and 2019 lidar data were made using the "Reclassify (Spatial Analyst)" tool to replace all valid values with 1 and setting the 'No Data' value to NoData to create a raster mask of data coverage for each source dataset. The "Raster to Polygon (Conversion)" tool was then used to convert those raster files to polygon shapefiles (SHP) representing the footprints of each dataset. The intersection of these footprints was generated using the "Intersect (Analysis)" tool and using the multibeam and lidar shapefile footprints as inputs to create the intersection footprint (Intersect_footprint SHP file). Both digital elevation models (DEMs) were then clipped to the extent of the intersect footprint using the "Clip (Data Management)" tool, creating the 2017_LKR_multibeam_19lidarExtent.tif and 2019_LKR_lidar_17multibeamExtent.tif files. Data sources used in this process:
    • 2017_LooeKey_Multibeam_Clip DEM
    • 2019 lidar data
    Data sources produced in this process:
    • Intersect_footprint SHP file
    • 2017_LKR_multibeam_19lidarExtent.tif
    • 2019_LKR_lidar_17multibeamExtent.tif
    Date: 2023 (process 3 of 11)
    Step 3: A 2-m grid was then created using the "Create Fishnet (Data Management)" tool, using the following parameters: Template extent: Intersect_footprint SHP file (created in Step 2); Cell size width: 2; Cell size height: 2; Number of Rows: left blank, Number of Columns: left blank; Geometry type: POLYLINE and box checked for 'Create Label Points'. The 2-m grid label points SHP file was clipped to the extent of the Intersect_footprint SHP file using the "Clip (Analysis)" tool by specifying the 2-m grid label points SHP file as the 'Input features' and the Intersect_footprint SHP file as the 'Clip features.' XY coordinates were added to the 2-m grid SHP file using the "Add XY Coordinates (Data Management)" tool, to create the 2m_grid point SHP file with coordinate fields POINT_X and POINT_Y in Universal Transverse Mercator (UTM) units. Data sources used in this process:
    • Intersect_footprint SHP file
    Data sources produced in this process:
    • 2m_grid point SHP file
    Date: 2023 (process 4 of 11)
    Step 4: Elevation values were extracted from the 2017 and 2019 DEMs at the location of the 2-m grid points in Global Mapper. The clipped 2017 DEM and the 2-m grid shapefile were loaded into Global Mapper, and the resampling method was changed to No Resampling (Nearest Neighbor) within the "Options" menu of the DEM. The 2-m grid was then selected using the "Digitizer" tool and within the "Attributes/Style Functions" window, "Apply Elevations to Selected Feature(s)" was selected, with "Terrain Layers" as the only selected parameter. An attribute named ELEVATION was created containing the 2017 DEM values. Using the "Digitizer" tool, the "Edit Selected Features" window was selected to rename the ELEVATION attribute to ELEV2017. The same steps were repeated for the clipped 2019 DEM, creating the ELEV2019 field. Data sources used in this process:
    • 2017_LKR_multibeam_19lidarExtent.tif
    • 2019_LKR_lidar_17multibeamExtent.tif
    • 2m_grid point SHP file
    Data sources produced in this process:
    • ELEV2017 field
    • ELEV2019 field
    Date: 2023 (process 5 of 11)
    Step 5: Elevation-differences between the ELEV2017 and ELEV2019 values were calculated using the "Digitizer" tool in Global Mapper. "Calculate/Copy Attributes for Feature Selection" was selected from the "Attribute/Style Functions" window. The elevation-difference was calculated using the following parameters: “Select Existing or Create New Attribute to Assign Calculated Values”: Diff_m; “Source Attribute”: ELEV2019; “Operation”: Subtract; and “Use Attribute Value”: ELEV2017. ELEV2019 represents the modern elevation values and ELEV2017 represents the historical elevation values in this analysis. The final 2-m grid was then exported as a shapefile, 1719_LKR_IntersectPoints.shp. Data sources used in this process:
    • ELEV2017 field
    • ELEV2019 field
    Data sources produced in this process:
    • LooeKey_1719_IntersectPoints.shp
    Date: 2023 (process 6 of 11)
    Step 6: Elevation change surface models were created in ArcGIS Pro using the calculated elevation-difference (Diff_m) field within the 1719_LKR_IntersectPoints.shp point shapefile. A triangular irregular networks (TIN) file was created from the Diff_m points using the "Create TIN (3D Analyst)" tool by specifying the 1719_LKR_IntersectPoints.shp shapefile as the "Input Feature Class", Diff_m as the "Height Field" and Mass_Points as the "Type", creating the 1719_LK_Diffm_TIN file. The TIN was then delineated using the "Delineate TIN Data Area (3D Analyst)" tool by specifying the 1719_LK_Diffm_TIN file as the "Input TIN", a "Maximum Edge Length" of 2.828428 (hypotenuse of a triangle with 2-m legs) and the "Method" set to ALL EDGES. Data sources used in this process:
    • 1719_LKR_IntersectPoints.shp
    Data sources produced in this process:
    • 1719_LK_Diffm_TIN file
    Date: 2023 (process 7 of 11)
    Step 7: The Unified Florida Reef Tract Map Version 2.0 shapefile was downloaded from Florida Fish and Wildlife Conservation Commission (2015). Using ArcGIS Pro, the habitat shapefile was modified using the "Clip (Analysis)" tool to clip the habitat shapefile to the extent of the 2017 and 2019 DEMs by specifying the habitat shapefile as the "Input Features" and the Intersect_footprint SHP file from step 2 as the "Clip Features", creating the LK_HabMap_Clip.shp file. The shapefile was then loaded into Global Mapper and exported using the 2011 realization of NAD83 as LK_Habmap_2011_GM_Export.shp. Data sources used in this process:
    • Unified Florida Reef Tract Map Version 2.0
    • Intersect_footprint SHP file
    Data sources produced in this process:
    • LK_HabMap_Clip.shp
    • LK_Habmap_2011_GM_Export.shp
    Date: 2023 (process 8 of 11)
    Step 8: The DEMs used in this analysis cover additional areas outside of the Unified Florida Reef Tract Map Version 2.0, so an additional polygon needed to be integrated into the shapefile. Using the "Erase (Analysis)" tool in ArcGIS Pro, the Intersect_footprint SHP file was used as the "Input Features" and the LK_HabMap_2011_GM_Export.shp file was used as the "Erase Features" creating the LK_HabMap_2011_GM_Export_UnclassifiedAdded file. The Unclassified_Polygons.shp shapefile was edited in an edit session to add the "ClassLv2" attribute and assign its value as "Unclassified.” The edit session was closed, and the changes were saved. Data sources used in this process:
    • Intersect_footprint SHP file
    • LK_Habmap_2011_GM_Export.shp
    Data sources produced in this process:
    • Unclassified_Polygons.shp
    Date: 2023 (process 9 of 11)
    Step 9: Using the "Merge (Data Management)" tool, the Unclassifed_Polygons.shp file and the LK_HabMap_2011_GM_Export.shp shapefile were used as the "Input Datasets" creating the 1719_LKR_habitat_clipped.shp file. Using the "Select by Attribute" tool, 11 individual habitat shapefiles were created from the LK_HabMap_2011_GM_Export_UnclassifiedAdded.shp file by selecting one ClassLv2 habitat and exporting it as a separate shapefile. Data sources used in this process:
    • Unclassified_Polygons.shp
    • LK_HabMap_2011_GM_Export.shp
    • UR_HabMap_2011_GM_Export_UnclassifiedAdded.shp
    Data sources produced in this process:
    • 1719_LKR_habitat_clipped.shp
    • 11 individual habitat shapefiles
    Date: 2023 (process 10 of 11)
    Step 10: Elevation change statistics were determined by habitat type from the LooeKey_1719_IntersectPoints.shp file. In ArcGIS Pro, the "Select Layer by Locations (Data Management)" tool was used to extract points within or on the boundary of a specific habitat type by using the following parameters: "Input Feature Layer": LooeKey_1719_IntersectPoints.shp; "Relationship": INTERSECT; "Selecting Features": Clipped Habitat shapefile; "Search Distance": left blank; and "Selection Type": NEW_SELECTION. An ArcGIS Pro model named Seafloor Elevation Change Analysis Tool (SECAT; Zieg and Zawada, 2021) was created to automate the process, as these steps were repeated for 11 habitat types across the extent of the study area. Elevation change statistics were compiled by habitat type into a single comma separated values (CSV) file, see 1719_LKR_Elevation_and_Volume_Statistics.zip for this file. Data sources used in this process:
    • 1719_LKR _IntersectPoints.shp
    • 1719_LKR _habitat_clipped.shp
    • SECAT model
    • 11 individual habitat shapefiles
    Data sources produced in this process:
    • 1719_LKR_elevationchange.csv
    Date: 2023 (process 11 of 11)
    Step 11: Volume change statistics per habitat type were calculated utilizing the TIN generated in Step 6. Surface volume changes were calculated using the "Surface Volume (3D Analyst)" tool in ArcGIS Pro. To calculate the net erosion lower limit, the "Reference Plane" was set to BELOW and the "Plane Height" was set to -0.19 m. For the net erosion upper limit, the "Reference Plane" was set to Below, and the "Plane Height" to 0 m. Net accretion lower and upper limits were calculated by setting the "Reference Plane" to ABOVE and the "Plane Height" to 0.19 m and 0 m for each case, respectively. The 0.19 m threshold was determined via vertical error analysis of the reported vertical uncertainties for the original 2017 multibeam (0.15 m) and 2019 lidar (0.11 m) to calculate a root mean square error (RMSE) of 0.19 m (Yates and others, 2017). The area normalized volume change lower limit was calculated by dividing the minimum net volume change for each habitat by the habitat's total area. The area normalized volume change upper limit was calculated by dividing the maximum net volume for each habitat by the habitat's total area. The SECAT model (Zieg and Zawada, 2021) was used to automate the process, as these steps were repeated for 11 habitat types. The volume statistics were compiled by habitat type into a single CSV file, see 1719_LKR_Elevation_and_Volume_Statistics.zip for this file. Data sources used in this process:
    • 1719_LK_Diffm_TIN file
    • 11 individual habitat shapefiles
    Data sources produced in this process:
    • 1719_LKR_volume.csv
  3. What similar or related data should the user be aware of?
    Yates, Kimberly K., Fehr, Zachery W., Johnson, Selena A., and Zawada, David G., 20240524, Impact of Hurricane Irma on coral reef sediment redistribution at Looe Key Reef, Florida, USA: Ocean Sciences Volume 20, Issue 3, European Geosciences Union, Online.

    Online Links:

    Other_Citation_Details: pages 661-688
    Yates, Kimberly K., Zawada, David G., Smiley, Nathan A., and Tiling-Range, Ginger, 20170420, Divergence of seafloor elevation and sea level rise in coral reef ecosystems: Biogeosciences Volume 14, Issue 16, European Geosciences Union, Online.

    Online Links:

    Other_Citation_Details: pages 1739–1772
    Organization, International Hydrographic, 200802, IHO Standards for Hydrographic Surveys: International Hydrographic Bureau, 4, quai Antoine 1er B.P. 445 - MC 98011 MONACO Cedex Principauté de Monaco.

    Online Links:

    Other_Citation_Details: 28 pages

How reliable are the data; what problems remain in the data set?

  1. How well have the observations been checked?
    The 2017–2018 and 2019 datasets were visually compared by USGS staff in ArcGIS Pro for identification of anomalous elevations or data inconsistencies following the methods of Yates and others (2017).
  2. How accurate are the geographic locations?
    The 2017–2018 multibeam data were collected and processed in accordance with International Hydrographic Organization (IHO) Special Order standards for positioning and depth (IHO, 2008). The Total Propagated Uncertainty values associated with the multibeam data are available in Fredericks and others (2019). The 2019 lidar data have a recorded horizontal accuracy of 0.115 meters (m) at the 95% confidence level using the National Standards for Spatial Data Accuracy (NSSDA) reporting method. The NSSDA report is included in 2018-2019 NOAA NGS Topobathy Lidar DEM Hurricane Irma: Miami to Marquesas Keys, FL metadata (National Geodetic Survey, 2020).
  3. How accurate are the heights or depths?
    The 2017–2018 multibeam data were collected and processed in accordance with International Hydrographic Organization (IHO) Special Order standards for positioning and depth (IHO, 2008). The Total Propagated Uncertainty values associated with the multibeam data are available in Fredericks and others (2019). The 2019 lidar data reported 0.110 m vertical accuracy at the 95% confidence level against the classified point cloud using NSSDA reporting standards. The NSSDA report is included in 2018-2019 NOAA NGS Topobathy Lidar DEM Hurricane Irma: Miami to Marquesas Keys, FL metadata (National Geodetic Survey, 2020).
  4. Where are the gaps in the data? What is missing?
    Dataset is considered complete for the information presented, as described in the abstract. Users are advised to carefully read the rest of the metadata record and refer to Yates and others (2017) for additional details.
  5. How consistent are the relationships among the observations, including topology?
    This dataset was derived from post-Hurricane Irma high-resolution lidar and multibeam DEM data. All elevation layers were georeferenced and aligned using standardized transformation methods. TIN models were generated in ArcGIS Pro to compute seafloor elevation and volume statistics. Data layers were clipped to a uniform extent to exclude “no data” values and ensure consistent spatial coverage across all layers.

How can someone get a copy of the data set?

Are there legal restrictions on access or use of the data?
Access_Constraints No access constraints. Please see 'Distribution Information' for details.
Use_Constraints These data are marked with a Creative Commons CC0 1.0 Universal License. These data are in the public domain and do not have any use constraints. Users are advised to read the dataset's metadata thoroughly to understand appropriate use and data limitations.
  1. Who distributes the data set? (Distributor 1 of 1)
    U.S. Geological Survey, St. Petersburg Coastal and Marine Science Center
    Attn: USGS SPCMSC Data Management
    600 4th Street South
    Saint Petersburg, FL
    United States

    727-502-8000 (voice)
    gs-g-spcmsc_data_inquiries@usgs.gov
  2. What's the catalog number I need to order this data set? 2017_LKR_multibeam_19lidarExtent.tif, 2019_LKR_lidar_17multibeamExtent.tif, 1719_LKR_habitat_clipped.shp, 1719_LKR_IntersectPoints.shp, 1719_LKR_elevationchange.csv, 1719_LKR_volume.csv, DataDictionary_ElevationChange.docx, DataDictionary_HabitatTypes.docx, DataDictionary_VolumeChange.docx
  3. What legal disclaimers am I supposed to read?
    Unless otherwise stated, all data, metadata and related materials are considered to satisfy the quality standards relative to the purpose for which the data were collected. Although these data and associated metadata have been reviewed for accuracy and completeness and approved for release by the U.S. Geological Survey (USGS), no warranty expressed or implied is made regarding the display or utility of the data for other purposes, nor on all computer systems, nor shall the act of distribution constitute any such warranty. Any use of trade, firm, or product names is for descriptive purposes only and does not imply endorsement by the U.S. Government.
  4. How can I download or order the data?

Who wrote the metadata?

Dates:
Last modified: 14-Nov-2025
Metadata author:
U.S. Geological Survey, St. Petersburg Coastal and Marine Science Center
Attn: USGS SPCMSC Data Management
600 4th Street South
Saint Petersburg, FL
United States

727-502-8000 (voice)
gs-g-spcmsc_data_inquiries@usgs.gov
Metadata standard:
Content Standard for Digital Geospatial Metadata (FGDC-STD-001-1998)
This page is <https://cmgds.marine.usgs.gov/catalog/spcmsc/1719_LooeKey_metadata.faq.html>
Generated by mp version 2.9.51 on Mon Nov 17 09:48:47 2025