Single-Beam Bathymetry Sounding Data of Charlotte Harbor and offshore Captiva Island, Florida (2003-2004) in XYZ format

Frequently anticipated questions:

• What does this data set describe?
  1. How might this data set be cited?
  2. What geographic area does the data set cover?
  3. What does it look like?
  4. Does the data set describe conditions during a particular time period?
  5. What is the general form of this data set?
  6. How does the data set represent geographic features?
  7. How does the data set describe geographic features?
• Who produced the data set?
  1. Who are the originators of the data set?
  2. Who also contributed to the data set?
  3. To whom should users address questions about the data?
• Why was the data set created?
• How was the data set created?
  1. From what previous works were the data drawn?
  2. How were the data generated, processed, and modified?
  3. What similar or related data should the user be aware of?
• How reliable are the data; what problems remain in the data set?
  1. How well have the observations been checked?
  2. How accurate are the geographic locations?
  3. How accurate are the heights or depths?
  4. Where are the gaps in the data? What is missing?
  5. How consistent are the relationships among the data, including topology?
• How can someone get a copy of the data set?
  1. Are there legal restrictions on access or use of the data?
  2. Who distributes the data?
  3. What's the catalog number I need to order this data set?
  4. What legal disclaimers am I supposed to read?
  5. How can I download or order the data?
• Who wrote the metadata?

What does this data set describe?

1. How might this data set be cited?
   Hansen, Mark, 2015, Single-Beam Bathymetry Sounding Data of Charlotte Harbor and offshore Captiva Island, Florida (2003-2004) in XYZ format: Archive of Bathymetry Data Collected in South Florida from 1995 to 2015 U.S. Geological Survey Data Series-1031, U.S. Geological Survey, St. Petersburg, Florida.

   Online Links:

   • https://doi.org/10.3133/ds1031

2. What geographic area does the data set cover?

   West_Bounding_Coordinate: -82.35908
   East_Bounding_Coordinate: -82.04828
   North_Bounding_Coordinate: 26.32486
   South_Bounding_Coordinate: 26.85241
   

3. What does it look like?
4. Does the data set describe conditions during a particular time period?

   Beginning_Date: 2003

   Ending_Date: 2004

   Currentness_Reference:

   Data assumed to be constant over time but may change due to geologic processes.

5. What is the general form of this data set?

   Geospatial_Data_Presentation_Form: tabular digital data
   

6. How does the data set represent geographic features?
   1. How are geographic features stored in the data set?
      This is a Point data set. It contains the following vector data types (SDTS terminology):
      • Point (634075)
   2. What coordinate system is used to represent geographic features?
      Horizontal positions are specified in geographic coordinates, that is, latitude and longitude. Latitudes are given to the nearest 0.0000001. Longitudes are given to the nearest 0.0000001. Latitude and longitude values are specified in decimal degrees. The horizontal datum used is WGS84-G1150.
      The ellipsoid used is WGS84.
      The semi-major axis of the ellipsoid used is 6378137.0.
      The flattening of the ellipsoid used is 1/298.257223563.
      

      Vertical_Coordinate_System_Definition:

      Depth_System_Definition:

      Depth_Datum_Name: NAVD88
      Depth_Resolution: 0.01
      Depth_Distance_Units: meters
      Depth_Encoding_Method: Explicit depth coordinate included with horizontal coordinates
      

7. How does the data set describe geographic features?

   DS1031_CharlotteH_WS84_NAVD88-G03_SB.xyz.txt, DS1031_CharlotteH_WS84_NAVD88-G03_SB.xyz.shp

   Post-processed, area-specific x,y,z attributed single-beam bathymetry data. (Source: USGS)

   FID

   Field ID (Source: USGS)

   Range of values
   Minimum:	0
   Maximum:	107106

   longitude

   WGS84(G1150) x-coordinate (easting) of sample point (Source: NOAA/NGS UTMS)

   Range of values
   Minimum:	-82.35908
   Maximum:	-82.04828
   Units:	decimal degrees
   Resolution:	0.00000001

   latitude

   WGS84(G1150) y-coordinate (northing) of sample point (Source: NOAA/NGS UTMS)

   Range of values
   Minimum:	26.32486
   Maximum:	26.85241
   Units:	decimal degrees
   Resolution:	0.00000001

   z-ellipsoid height

   WGS84(G1150) ellipsoid height of sample point, in meters (Source: SANDS)

   Range of values
   Minimum:	-45.954
   Maximum:	-24.258
   Units:	meters
   Resolution:	0.001

   z-NAVD88

   Orthometric height of sample point, in meters. Relative to geoid model Geoid99. (Source: SANDS)

   Range of values
   Minimum:	-22.203
   Maximum:	-0.667
   Units:	meters
   Resolution:	0.001

Who produced the data set?

1. Who are the originators of the data set? (may include formal authors, digital compilers, and editors)
   • Mark Hansen
2. Who also contributed to the data set?

   South Florida Water Management District (SFWMD) provided funding for the study. The project was conducted as a cooperative study by personnel from the USGS in St. Petersburg, FL and the SFWMD, in Fort Myers, FL. Mark Hansen was the USGS principal investigator. Gina Perry performed a significant portion of bathymetric survey data collection and processing.

3. To whom should users address questions about the data?
   Mark Hansen

   U.S. Geological Survey

   Oceanographer

   600 Fourth Street South

   St. Petersburg, FL
   

   USA

   (727) 502-8000 (voice)

   mhansen@usgs.gov

Why was the data set created?

This project supports several SFWMD efforts including the Caloosahatchee MFL, the Southwest Florida Feasibility Study, and the SWIM designation of Charlotte Harbor. In addition, a need for a Charlotte Harbor estuarine mixing model has been identified by the Southwest Florida Regional Restoration Coordination Team and the Southwest Florida Feasibility Study.
In order to create an accurate model, current bathymetric data was obtained for the Charlotte Harbor system. Bathymetry data was also needed for the creation of a seagrass vision map (an NEP effort) and to populate the species response models being created as assessment tools for the restoration program. This project addresses the collection and interpretation of data necessary to develop the present day bathymetry of the lower portion of Charlotte Harbor, which includes Pine Island Sound, the region offshore of from Little Gaspiralla Island to south Captiva Island, Florida.

How was the data set created?

1. From what previous works were the data drawn?

   USGS Charlotte Harbor bathymetry (source 1 of 1)

   U.S. Geological Survey, Unpublished material, 2003-2004 Charlotte Harbor, Florida single-beam bathymetry.

   Type_of_Source_Media: digital tabular data
   Source_Contribution: Original processed single-beam bathymetric data
   

2. How were the data generated, processed, and modified?

   Date: 2004 (process 1 of 5)

   Data Acquisition - The sea-floor of Charlotte Harbor and offshore Captiva Island was mapped by using an outboard motor boat, equipped with a high-precision Global Positioning Systems (GPS) coupled with a high-precision depth sounder. To accomplish this task, the SANDS (System for Accurate Nearshore Depth Surveying) system was developed by Mark Hansen (SPCMSC) and Jeff List (WHSC) of the U.S. Geological Survey. SANDS consists of two components, hardware and processing techniques.
   Survey track lines were spaced 500-meters apart and orientated shore normal along the project area. Track lines collected parallel to the coast (intersecting track lines) functioned to serve as a cross-check and to assess the relative vertical accuracy of the survey. Crossing lines are critical because they serve as a check on the internal accuracy of the data. Soundings were collected along each track line at 3 m spacing. In shallow areas, data were collected in a minimum of 0.3 m water depth except where there was potential damage to the bottom environment or the boat/motors.
   Reference GPS reference stations were operated on an USGS bench mark, typically located within approximately 15 km of the farthest single-beam track line. Reference and rover GPS receivers recorded the 12-channel full-carrier-phase positioning signals (L1/L2) from satellites via ASHTECH choke-ring antennas. The reference and rover receivers record their positions concurrently at 1-second(s) recording intervals throughout the survey.
   Boat motion was recorded at 50-millisecond (ms) intervals using a TSS Dynamic Motion Sensor 05 (TSS DMS-05). Bathymetric soundings were recorded at 10-ms intervals using an Marimatech EC-100 survey grade echo-sounder. The single-beam data were acquired using the hydrographic software HYPACK version 5. All data strings from the instruments were streamed in real time and recorded through HYPACK software. Person who carried out this activity:
   

   U.S. Geological Survey

   Attn: Mark Hansen

   Oceanographer

   600 4th Street South

   St. Petersburg, FL
   

   USA

   (727) 502-8000 (voice)

   mhansen@usgs.gov

   Data sources produced in this process:

   • Raw sensor data files in ASCII text format and GPS Carrier-phase data in binary format.

   Date: 2004 (process 2 of 5)

   Differentially Corrected Navigation Processing- The coordinate values of the reference GPS base stations obtained from OPUS were provided in the ITRF00 coordinate system. All survey data for the project was referenced to WGS84. Consequently, reference station coordinates were transformed to WGS84 coordinates using the NOAA/NGS software HTDP v1.3. The respective reference (base) station coordinates utilized as reference positions were imported into PNAV v2.0 software by ASHTECH, Inc. Differentially corrected rover trajectories were computed by merging the master and rover the GPS data. During processing, steps were taken to ensure that the trajectories between the base and rover were clean, resulting in fixed positions. By analyzing the graphs, trajectory maps, and processing logs that GrafNav produces for each GPS session, GPS data from satellites flagged by the program as having poor health or satellite time segments that had cycle slips could be excluded, or the satellite elevation mask angle could be adjusted to improve the position solutions. The final differentially corrected precise DGPS positions were computed for each rover GPS session and exported in ASCII text format. Person who carried out this activity:
   

   Mark Hansen

   U.S. Geological Survey

   Oceanographer

   600 Fourth St. South

   St. Petersburg, FL
   

   727-502-8000 (voice)

   727-502-8032 (FAX)

   mhansen@usgs.gov

   Data sources produced in this process:

   • Boat trajectory data files in ASCII text format.

   Date: 2004 (process 3 of 5)

   Single-beam Bathymetry Processing- All data were processed using SANDS version 1.2. The primary purpose of SANDS is to time synchronize processed trajectories, soundings, and heave/pitch/roll, then merge all data strings. SANDS applies latency errors, applies geometric corrections for antenna staff pitch and roll, applies geometric corrections for antenna transducer pitch and roll (beam correction), time synchronizes the GPS trajectory and HYPACK files for each GPS epoch, and converts WGS84 latitude/longitude coordinates to North American Datum of 1983 NAD83/GRS80 UTM coordinates (m), and applies a geoid separation based upon the NOAA/NGS Geoid03 model. Latitude/longitude conversion to UTM coordinates was accomplished using NOAA/NGS UTM v2.0 software. Intermediate output files are comma delimited text files containing: time of day (seconds of day), UTM X coordinate (m), UTM Y coordinate (m), ellipsoid height, orthometric height, smoothed raw depths, PNAV RMS value, and HYPACK line number. A header line indicates the attributes entry for each column. Person who carried out this activity:
   

   Mark Hansen

   U.S. Geological Survey (USGS) - St. Petersburg Coastal and Marine Science Center

   Oceanographer

   600 4th Street South

   St. Petersburg, FL
   

   USA

   727-502-8000 (voice)

   727-502-8032 (FAX)

   mhansen@usgs.gov

   Data sources used in this process:

   • Completely processed final XYZ files representing sea-floor elevations.

   Data sources produced in this process:

   • Final processed bathymetry data files in ASCII text format.

   Date: 2015 (process 4 of 5)

   The final processed bathymetry files were reformatted for publication. UTM coordinate were converted to latitude/longitude using NOAA/NGS UTMS v2.0 software. Shapefiles were created from X,Y,Z text files using in-house developed software. Person who carried out this activity:
   

   U.S. Geological Survey

   Attn: Mark Hansen

   Oceanographer

   600 4th Street South

   St. Petersburg, FL
   

   USA

   (727) 502-8000 (voice)

   (727) 502-8032 (FAX)

   mhansen@usgs.gov

   Data sources produced in this process:

   • DS1031_CharlotteH_WS84_NAVD88-G03_SB.xyz.txt, DS1031_CharlotteH_WS84_NAVD88-G03_SB.xyz.shp

   Date: 13-Oct-2020 (process 5 of 5)

   Added keywords section with USGS persistent identifier as theme keyword. Person who carried out this activity:
   

   U.S. Geological Survey

   Attn: VeeAnn A. Cross

   Marine Geologist

   384 Woods Hole Road

   Woods Hole, MA
   

   508-548-8700 x2251 (voice)

   508-457-2310 (FAX)

   vatnipp@usgs.gov

3. What similar or related data should the user be aware of?
   Hansen, Mark Eduardo Patino, 2003, Hydrodynamic and Bathymetric Characteristics of South Florida Estuarine and Coastal Systems: USGS South Florida Information Access (SOFIA) SOFIA, U.S. Geological Survey, St. Petersburg, FL.

   Online Links:

   • http://sofia.usgs.gov/projects/index.php?project_url=hires_bathy

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

1. How well have the observations been checked?
   The accuracy of the data is determined during data collection. This dataset is derived from a multiple research cruises using identical equipment, set-ups, and staff; therefore, it is internally consistent. Methods are employed to maintain data collection consistency aboard the platform. During mobilization, each piece of equipment is isolated to obtain internal and external offset measurements with respect to the survey platform. All the critical measurements are recorded manually and digitally entered into their respective programs. Offsets between the single-beam transducers and the Ashtech antenna reference point (ARP) were measured and accounted for in post-processing. Bar checks were performed as calibration efforts and accounted for any drift in the Marimatech Echosounder. Differential Geographic Positioning System (DGPS) coordinates were obtained using post-processing software packages developed by the National Oceanic and Atmospheric Administration (NOAA)/National Geodetic Survey (NGS) Online Positioning User Service (OPUS), National Aeronautics and Space Administration (NASA)/Jet Propulsion Laboratory (JPL) Online Positioning User Service (GIPSY), and Scripps Orbit and Permanent Array Center Online Positioning User Service (SCOUT). Boat trajectories were computed with PNAV v2.0 software by ASHTECH, Inc. These bathymetric data have not been independently verified for accuracy.
2. How accurate are the geographic locations?
   The GPS antenna and receiver acquisition configuration used at the reference station was duplicated on the survey vessel (rover). The base receiver and the rover receiver record their positions concurrently at 1Hz recording intervals throughout the survey. All processed measurements are referenced to the base station coordinates.
   GPS base or differential reference stations were operated within approximately 15 to 20 km of the survey area. Five new temporary ground-control points or benchmarks (surveyed to within 1 cm to 2 cm accuracy) were established throughout the study area for use as reference receiver sites using standard benchmarks procedures. The new benchmarks were surveyed using Ashtech Z-12, 12 channel dual-frequency GPS receivers. Full-phase carrier data were recorded on each occupied benchmark in Ashtech proprietary BIN format with daily occupations ranging from 6 to 12 hours. BIN files were then converted to RINEX-2 format for position processing.
   All static base station GPS sessions were submitted for processing to the online OPUS, GIPSY, and SCOUT system software. The computed base location results were entered into a spreadsheet to compute one final positional coordinate and error analysis for that base location. The final positional coordinate (latitude, longitude, and ellipsoid height) is the weighted average of all GPS sessions. For each GPS session, the weighted average was calculated from the total session time in seconds; therefore, longer GPS occupation times held more value than shorter occupation times. Results were computed relative to ITRF00 coordinate system. The established geodetic reference frame for the project was WGS84. Therefore, final reference coordinates used to process the rover data were transformed from ITRF00 to WGS84 using National Oceanic and Atmospheric Administration/National Geodetic Survey(NOAA/NGS) HTDP software v2.1.
   OPUS, GIPSY, and SCOUT results provide an error measurement for each daily solution. Applying these error measurements, the horizontal accuracy of the base station is estimated to be 0.04 (m) root mean squared (RMS).
   The kinematic (rover) trajectories were processed using PNAV v2.0, by ASHTECH, Inc. A horizontal error measurement, RMS is computed for each epoch. The horizontal trajectory errors for varied between 0 and 0.08(m).
   The combined horizontal error from base station coordinate solutions and rover trajectories range from 0 and 0.12 (m), with the average approximately 0.06 (m).
3. How accurate are the heights or depths?
   The GPS antenna and receiver acquisition configuration used at the reference station was duplicated on the survey vessel (rover). The base receiver and the rover receiver record their positions concurrently at 1Hz recording intervals throughout the survey. All processed measurements are referenced to the base station coordinates.
   GPS base or differential reference stations were operated within approximately 15 to 20 km of the survey area. Five new temporary ground-control points or benchmarks (surveyed to within 1 cm to 2 cm accuracy) were established throughout the study area for use as reference receiver sites using standard benchmarks procedures. The new benchmarks were surveyed using Ashtech Z-12, 12 channel dual-frequency GPS receivers. Full-phase carrier data were recorded on each occupied benchmark in Ashtech proprietary BIN format with daily occupations ranging from 6 to 12 hours. BIN files were then converted to RINEX-2 format for position processing.
   All static base station GPS sessions were submitted for processing to the online OPUS, GIPSY, and SCOUT system software. The computed base location results were entered into a spreadsheet to compute one final positional coordinate and error analysis for that base location. The final positional coordinate (latitude, longitude, and ellipsoid height) is the weighted average of all GPS sessions. For each GPS session, the weighted average was calculated from the total session time in seconds; therefore, longer GPS occupation times held more value than shorter occupation times. Results were computed relative to ITRF00 coordinate system. The established geodetic reference frame for the project was WGS84. Therefore, final reference coordinates used to process the rover data were transformed from ITRF00 to WGS84 using National Oceanic and Atmospheric Administration/National Geodetic Survey(NOAA/NGS) HTDP software v2.1.
   OPUS, GIPSY, and SCOUT results provide an error measurement for each daily solution. Applying these error measurements, the vertical accuracy of the base station is estimated to be 0.04 (m) root mean squared (RMS).
   The kinematic (rover) trajectories were processed using PNAV v2.0, by ASHTECH, Inc. A vertical error measurement, RMS is computed for each epoch. The vertical trajectory errors for varied between 0 and 0.08(m).
   The combined vertical error from base station coordinate solutions and rover trajectories range from 0 and 0.14 (m), with the average approximately 0.08 (m).
4. Where are the gaps in the data? What is missing?
   These are complete post-processed x,y,z bathymetric data points from acoustic single-beam system collected in 2003-2004 in Charlotte Harbor and offshore Captiva Island, Florida.
5. How consistent are the relationships among the observations, including topology?
   This dataset was acquired on multiple research cruises in 2003-2004 with identical hardware and software systems.

How can someone get a copy of the data set?

Are there legal restrictions on access or use of the data?

Access_Constraints:

The U.S. Geological Survey requests that it be referenced as the originator of this dataset in any future products or research derived from these data.

Use_Constraints: These data should not be used for navigational purposes.

1. Who distributes the data set? (Distributor 1 of 1)
   
   Mark E. Hansen

   U.S. Geological Survey

   Oceanographer

   600 Fourth St. South

   St. Petersburg, FL
   

   (727) 502-8000 (voice)

   (727) 502-8032 (FAX)

   mhansen@usgs.gov
2. What's the catalog number I need to order this data set? Single-beam bathymetry, vessel (R/V Streeterville) acquired, bathymetric data
3. What legal disclaimers am I supposed to read?

   The data have no explicit or implied guarantees. Any use of trade, firm, or product names is for descriptive purposes only and does not imply endorsement by the U.S. Government. 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 or the U.S. Government shall not be held liable for improper or incorrect use of the data described and/or contained herein.

4. How can I download or order the data?
   • Availability in digital form:

     Data format:	ASCII
     Network links:	https://pubs.usgs.gov/ds/1031/download/CharlotteH/soundings/DS1031-CharlotteH_WGS84_NAVD88-G03_SB_txt.xyz.zip

   • Cost to order the data: none

Who wrote the metadata?

Dates:

Last modified: 13-Oct-2020

Metadata author:

U.S. Geological Survey

Attn: Mark Hansen

Oceanographer

600 4th Street South

St. Petersburg, FL

USA

(727) 502-8000 (voice)

mhansen@usgs.gov

Metadata standard:

FGDC Content Standard for Digital Geospatial Metadata (FGDC-STD-001-1998)