Bathymetry data for Santa Cruz Harbor, California collected during USGS field activity 2022-609-FA

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?
   Dartnell, Peter, and Jaffe, Bruce E., 20230322, Bathymetry data for Santa Cruz Harbor, California collected during USGS field activity 2022-609-FA: data release DOI:10.5066/P9IY4ZEK, U.S. Geological Survey, Pacific Coastal and Marine Science Center, Santa Cruz, California.

   Online Links:

   • https://doi.org/10.5066/P9IY4ZEK

   This is part of the following larger work.
   Dartnell, Peter, and Jaffe, Bruce E., 2023, Bathymetry and acoustic backscatter data for Santa Cruz Harbor, California collected during USGS field activity 2022-609-FA: data release DOI:10.5066/P9IY4ZEK, U.S. Geological Survey, Pacific Coastal and Marine Science Center, Santa Cruz, CA.

   Online Links:

   • https://doi.org/10.5066/P9IY4ZEK

2. What geographic area does the data set cover?

   West_Bounding_Coordinate: -122.017
   East_Bounding_Coordinate: -121.998
   North_Bounding_Coordinate: 36.973
   South_Bounding_Coordinate: 36.956
   

3. What does it look like?

   https://cmgds.marine.usgs.gov/data-releases/datarelease/10.5066-???/name=SCharbor_bathymetry_QV.jpg&allowOpen=true (JPEG)

   Quick view image of the Santa Cruz harbor bathymetry data.

4. Does the data set describe conditions during a particular time period?

   Beginning_Date: 26-Jan-2022

   Ending_Date: 26-Jan-2022

   Currentness_Reference:

   ground condition at time data were collected.

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

   Geospatial_Data_Presentation_Form: GeoTIFF
   

6. How does the data set represent geographic features?
   1. How are geographic features stored in the data set?
      This is a Raster data set. It contains the following raster data types:
      • Dimensions 1907 x 1646 x 1, type Grid Cell
   2. What coordinate system is used to represent geographic features?
      

      Grid_Coordinate_System_Name: Universal Transverse Mercator
      Universal_Transverse_Mercator:

      UTM_Zone_Number: 10
      Transverse_Mercator:

      Scale_Factor_at_Central_Meridian: 0.9996
      Longitude_of_Central_Meridian: -123.00000
      Latitude_of_Projection_Origin: 0.00000
      False_Easting: 500000.0
      False_Northing: 0.00
      

      Planar coordinates are encoded using coordinate pair
      Abscissae (x-coordinates) are specified to the nearest 1.0
      Ordinates (y-coordinates) are specified to the nearest 1.0
      Planar coordinates are specified in Meters
      The horizontal datum used is North American Datum of 1983, 2011 realization (NAD83(2011)).
      The ellipsoid used is GRS80.
      The semi-major axis of the ellipsoid used is 6378137.00.
      The flattening of the ellipsoid used is 1/298.257222101.
      

      Vertical_Coordinate_System_Definition:

      Altitude_System_Definition:

      Altitude_Datum_Name: North America Vertical Datum 1988
      Altitude_Resolution: 0.1
      Altitude_Distance_Units: meters
      Altitude_Encoding_Method:

      Explicit elevation coordinate included with horizontal coordinates

7. How does the data set describe geographic features?

   value

   depth in meters relative to NAVD-88 (Source: Producer defined)

   Entity_and_Attribute_Overview:

   The complete 1-m resolution grid "SCharbor_1m_bathymetry_NAD83_NAVD88.tif" was originally archived as a TIFF image with the following attributes.
   

   Cell size = 1.0
   Number of rows = 1907
   Number of columns = 1646
   
   Data type = floating point
   
   Boundary
   Xmin = 587546
   Xmax = 589192
   Ymin = 4090475
   Ymax = 4092382
   
   Statistics
   Minimum value = -9.77
   Maximum value = -0.04
   Mean = -6.10
   Standard deviation = 2.73
   
   Coordinate system description
   Projection:  UTM
   Zone:  10
   Datum:  NAD83(2011)
   Vertical Reference: NAVD88
   Units:  meter[CSA1]
   

   Entity_and_Attribute_Detail_Citation: U.S. Geological Survey
   

Who produced the data set?

1. Who are the originators of the data set? (may include formal authors, digital compilers, and editors)
   • Peter Dartnell
   • Bruce E. Jaffe
2. Who also contributed to the data set?
3. To whom should users address questions about the data?
   U.S. Geological Survey, Pacific Coastal and Marine Science Center

   Attn: PCMSC Science Data Coordinator

   2885 Mission Street

   Santa Cruz, CA
   

   831-427-4747 (voice)

   pcmsc_data@usgs.gov

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?

   Date: 2023 (process 1 of 1)

   The Swath bathymetric survey was conducted with a SWATHplus-M 234-kHz interferometric side-scan sonar system pole-mounted on the U.S. Geological Survey (USGS) R/V San Lorenzo. During the mapping mission, an Applanix POS-MV (Position and Orientation System for Marine Vessels) was used to position the vessel during data collection, and it also accounted for vessel motion such as heave, pitch, and roll. The POS-MV also recorded position and vessel motion parameters for later post-processing. Sound-velocity profiles were collected throughout the survey day with a Castaway sound velocimeter. Post-processed POS-MV Smoothed Best Estimate of Trajectory (SBET) files were merged with the survey line files using BathySwath software and then the line files were imported into SonarWiz software. Soundings were cleaned for obvious errors and gridded into a 1-m base surface. The base surface was exported as an Erdas Imagine file in UTM-10, WGS-84 coordinates vertically referenced to the WGS84 ellipsoid. The grid was re-projected to UTM-10, NAD83 coordinates using "Project Raster" tool in ArcToolbox. NOAA's on-line VDATUM transformation tool states there is a +33.98m difference between WGS-84 and NAVD-88 elevations (vertical uncertainty of 0.06m) at a point in the center of the survey area. A value of 33.98 was added to the original bathymetry grid to transform from WGS-84 elevations to NAVD-88 elevations. The NAVD-88 bathymetry grid was then exported as a geoTIFF file in UTM zone 10, NAD-83(2011) coordinates, relative to NAVD88.

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?
   The SWATHPlus sonar system's (234 kHz) depth accuracy reduces with horizontal range. The system has an estimated vertical depth uncertainty ranging from about 0.05 m to 0.34 m over a horizontal range of 0 to 90 m (http://www.bathyswath.com/sites/default/files/documents/ETD_2002_Bathyswath%20information_EN.pdf). Accuracies of final products may be lower due to total propagated uncertainties of the mapping systems, which include sonar system, position and motion compensation system, and navigation, as well as data processing that includes sounding cleaning, gridding, and datum transformations. Comparing these data with previously published bathymetry data of northern Monterey Bay (https://pubs.usgs.gov/ds/514/) showed there is a mean difference of 0.02m in the overlap regions.
2. How accurate are the geographic locations?
   The Applanix POS-MV post-processed horizontal positional accuracy is about 0.1 m with roll and pitch accuracies of about 0.02 degrees (https://www.applanix.com/downloads/products/specs/posmv/POS-MV-WaveMaster-II.pdf). The SWATHPlus sonar system (234 kHz) has an across track resolution of about 5 cm (http://www.bathyswath.com/sites/default/files/documents/ETD_2002_Bathyswath%20information_EN.pdf). Accuracies of final products may be lower due to total propagated uncertainties of the mapping systems, which include sonar system, position and motion compensation system, and navigation, as well as data processing that includes sounding cleaning, gridding, and datum transformations.
3. How accurate are the heights or depths?
   The Applanix POS-MV post-processed vertical positional accuracy is about 0.2 m (https://www.applanix.com/downloads/products/specs/posmv/POS-MV-WaveMaster-II.pdf). The SWATHPlus sonar system (234 kHz) has a measurement resolution limit of about 0.6 cm and a resolution detection limit of about 3 mm (http://www.bathyswath.com/sites/default/files/documents/ETD_2002_Bathyswath%20information_EN.pdf). Accuracies of final products may be lower due to total propagated uncertainties of the mapping systems, which include sonar system, position and motion compensation system, and navigation, as well as data processing that includes sounding cleaning, gridding, and datum transformations.
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 read the rest of the metadata record carefully for additional details.
5. How consistent are the relationships among the observations, including topology?
   No formal logical accuracy tests were conducted

How can someone get a copy of the data set?

1. Who distributes the data set? (Distributor 1 of 1)
   
   U.S. Geological Survey - CMGDS

   2885 Mission Street

   Santa Cruz, CA
   

   831-427-4747 (voice)

   pcmsc_data@usgs.gov
2. What's the catalog number I need to order this data set? These data are available in GeoTIFF format, including a tif world file (.tfw) and are accompanied by CSDGM FGDC-compliant metadata.
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 on any other system or for general or scientific purposes, nor shall the act of distribution constitute any such warranty.
4. How can I download or order the data?
   • Availability in digital form:

     Data format:	Downloadable zip file contains the TIFF (.tif) version of the bathymetry data and a projection file (.tfw). in format GeoTIFF (version ArcMap (version 10.3.1)) Size: 1.02
     Network links:	https://cmgds.marine.usgs.gov/data-releases/datarelease/10.5066-P9IY4ZEK/name=SCharbor_1m_bathymetry_NAD83_NAVD88.zip/ https://doi.org/10.5066/P9IY4ZEK

   • Cost to order the data: None.

5. What hardware or software do I need in order to use the data set?
   The downloadable data file has been compressed with the "zip" command and can be unzipped with Winzip (or other tool) on Windows systems. To utilize these data, the user must have software capable of uncompressing the WinZip file and importing and viewing a GeoTIFF file.

Who wrote the metadata?

Dates:

Last modified: 22-Mar-2023

Metadata author:

U.S. Geological Survey, Pacific Coastal and Marine Science Center

Attn: PCMSC Science Data Coordinator

2885 Mission Street

Santa Cruz, CA

831-427-4747 (voice)

pcmsc_data@usgs.gov

Metadata standard:

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