Benthic Habitats of American Samoa Derived from Sonar and IKONOS Imagery, 2001-2012

Metadata also available as - [Outline] - [Parseable text] - [XML]

Frequently anticipated questions:


What does this data set describe?

Title:
Benthic Habitats of American Samoa Derived from Sonar and IKONOS Imagery, 2001-2012
Abstract:
This project is a cooperative effort between the National Ocean Service, National Centers for Coastal Ocean Science, Center for Coastal Monitoring and Assessment, Biogeography Branch, the Pacific Islands Benthic Mapping Center, the National Marine Fisheries Service, Pacific Islands Fishery Science Center, Coral Reef Ecosystem Division, University of Hawaii, BAE Spectral Solutions, and Analytical Laboratories of Hawaii, LLC. The goal of the work was to map the coral reef habitats from shoreline to shelf edge of Tutuila, American Samoa by visual interpretation and manual delineation of sonar and IKONOS satellite imagery. A three part habitat classification system was used. Benthic features were mapped as polygons and labeled with geomorphologic structure, reef zone, and percent hard bottom attributes.
  1. How should this data set be cited?

    Department of Commerce (DOC), National Oceanic and Atmospheric Administration (NOAA), National Ocean Service (NOS), National Centers for Coastal Ocean Sciences (NCCOS), Center for Coastal Monitoring and Assessment (CCMA), and Analytical Laboratories of Hawaii, 2012, Benthic Habitats of American Samoa Derived from Sonar and IKONOS Imagery, 2001-2012: NOAA's Ocean Service, National Centers for Coastal Ocean Science (NCCOS), Silver Spring, Maryland.

    This is part of the following larger work.

    Department of Commerce (DOC), National Oceanic and Atmospheric Administration (NOAA), National Ocean Service (NOS), National Centers for Coastal Ocean Science (NCCOS), Center for Coastal Monitoring and Assessment (CCMA), Biogeography Program, 2012, Shoreline to Shelf Edge Benthic Habitat Map of Tutuila, American Samoa Prepared by Visual Interpretation from Remote Sensing Imagery: NOAA's Ocean Service, National Centers for Coastal Ocean Science (NCCOS), Silver Spring, MD.

  2. What geographic area does the data set cover?

    West_Bounding_Coordinate: -170.92905
    East_Bounding_Coordinate: -170.48096
    North_Bounding_Coordinate: -14.19588
    South_Bounding_Coordinate: -14.38429

  3. What does it look like?

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

    Beginning_Date: 2002
    Ending_Date: 2010
    Currentness_Reference: ground condition

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

    Geospatial_Data_Presentation_Form: vector 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):

      • G-polygon (2089)

    2. What coordinate system is used to represent geographic features?

      Grid_Coordinate_System_Name: Universal Transverse Mercator
      Universal_Transverse_Mercator:
      UTM_Zone_Number: -2
      Transverse_Mercator:
      Scale_Factor_at_Central_Meridian: 0.999600
      Longitude_of_Central_Meridian: -171.000000
      Latitude_of_Projection_Origin: 0.000000
      False_Easting: 500000.000000
      False_Northing: 10000000.000000

      Planar coordinates are encoded using coordinate pair
      Abscissae (x-coordinates) are specified to the nearest 0.001024
      Ordinates (y-coordinates) are specified to the nearest 0.001024
      Planar coordinates are specified in meters

      The horizontal datum used is D_North_American_1983_HARN.
      The ellipsoid used is Geodetic Reference System 80.
      The semi-major axis of the ellipsoid used is 6378137.000000.
      The flattening of the ellipsoid used is 1/298.257222.

  7. How does the data set describe geographic features?

    tutuila_shore_to_shelfedge_final
    Shapefile attribute table (Source: None)

    FID
    Internal feature number. (Source: ESRI)

    ESRI

    Shape
    Feature geometry. (Source: ESRI)

    Coordinates defining the features.

    OBJECT_ID
    Incremental value generated for QA/QC adjacency test (Source: ArcView script)

    Incremental numeric field

    ZONE_
    Geomorphologic zone (Source: Habitat classification scheme)

    Assigned during digitizing character field

    M_STRUCT
    Major reef structure (Source: Habitat digitizing extension)

    Assigned during digitizing character field

    D_STRUCT
    Detailed structure (Source: Habitat digitizing extension)

    Assigned during digitizing character field

    P_HARD
    Percent hard bottom in the polygon (Source: Habitat classification scheme)

    Assigned during digitizing character field

    Shape_area
    Area of polygon (Source: ArcGIS script)

    Range of values
    Minimum:10.03
    Maximum:200389160.20
    Units:NA

    Shape_leng
    Length of polygon (Source: ArcGIS script)

    Range of values
    Minimum:13.84
    Maximum:925134.59
    Units:NA


Who produced the data set?

  1. Who are the originators of the data set? (may include formal authors, digital compilers, and editors)

  2. Who also contributed to the data set?

    Matt Kendall, NOAA and Miles Anderson, Analytical Laboratories of Hawaii

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

    National Oceanic and Atmospheric Administration (NOAA), National Ocean Service (NOS), National Centers for Coastal Ocean Science (NCCOS), Center for Coastal Monitoring and Assessment (CCMA), Biogeography Program
    Biogeography Branch, Marine Biologist
    1305 East West Highway
    Silver Spring, MD 20910

    301-713-3028 (voice)
    301-713-4384 (FAX)
    matt.kendall@noaa.gov

    Hours_of_Service: 0800 - 1700, Monday to Friday, EST


Why was the data set created?

The National Ocean Service is digitally mapping biotic resources to support long-term monitoring programs and detect and predict change in U.S. coral reefs, and their associated habitats and biological communities.


How was the data set created?

  1. From what previous works were the data drawn?

    Classification Scheme for Benthic Habitats of the Pacific (source 1 of 5)
    Coyne, M.S., 2003, Classification Scheme for Benthic Habitats of the Pacific: NOAA's Ocean Service, National Centers for Coastal Ocean Science (NCCOS), Silver Spring, MD.

    Online Links:

    Type_of_Source_Media: Report
    Source_Contribution:
    This document identified the zone, structure and biological cover types attributed in the data set

    Habitat Digitizer (source 2 of 5)
    Buja, Ken, 2003, Coral Reef Digitizing Extension: NOAA's Ocean Service (NOS), National Centers for Coastal Ocean Science (NCCOS), Silver Spring, MD.

    Online Links:

    Type_of_Source_Media: computer program
    Source_Contribution:
    This ArcView extension was used to digitize and attribute benthic zones, structure and percent hard bottom of this map.

    IKONOS imagery (source 3 of 5)
    Inc., Space Imaging , 2003, IKONOS Satellite Imagery: Space Imaging Inc., Thornton, CO.

    Other_Citation_Details:
    This imagery was obtained at a 4 m pixel resolution, corrected for water column and atmospheric effects, deglinted and Pan sharpened.
    Type_of_Source_Media: CD-ROM
    Source_Contribution:
    Used to identify and digitize benthic habitats for American Samoa.

    Sonar imagery (source 4 of 5)
    Pacific Islands Benthic Habitat Mapping Center, 2006, Sonar imagery and derived products for Tutuila: PIBHMC, Honolulu, HI.

    Online Links:

    Other_Citation_Details:
    Sonar bathymetry was obtained at 5 m pixel resolution and backscatter was collected 1 m resolution.
    Type_of_Source_Media: online arcGIS files
    Source_Contribution:
    Used to identify and digitize benthic habitats for American Samoa.

    Drop camera video (source 5 of 5)
    Department of Marine and Wildlife Resources, American Samoa, 2010, Drop Camera Videos for Fisheries Assessment: Department of Marine and Wildlife Resources, American Samoa, Pago Pago, AS.

    Other_Citation_Details:
    Video of sea floor features collected with GPS coordinate stamp.
    Type_of_Source_Media: video files
    Source_Contribution: Used to determine thematic accuracy of benthic habitat maps.

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

    Date: 2011 (process 1 of 2)
    Benthic habitat maps were digitized by delineating habitat boundaries from georeferenced sonar and orthorectified IKONOS satellite imagery loaded into ArcGIS software with the NOAA Habitat Digitizing extension activated. Digitizing was conducted using on computer screen methods with the minimum mapping unit (MMU) set to 1 acre and the image scale at 1:6,000 for IKONOS and 1:10,000 for sonar.

    A first draft map was completed and features in the imagery where uncertainties existed, due to confusing or difficult to interpret signatures, were identified for ground validation. An ArcGIS point theme was generated with points positioned on the features of uncertain habitat type or along transects though gradients between habitat types. The GIS points were converted to GPS waypoints and were navigated to in the field using a Trimble GeoExplorer 3 GPS data logger.

    A benthic habitat characterization was conducted at each site by drop camera, free diving, or where water depth and clarity permitted, by observation from the surface. GPS data were collected at each location and site ID, depth, habitat type, zone and the method used to make the assessment were recorded. A second draft of the map was generated incorporating these ground validation data.

    The sonar and satellite based maps were edge matched primarily by clipping out any areas of overlap and retaining the sonar derived map. Polygon edges were merged where attributes matched and seams corrected for any inconsistencies.

    Person who carried out this activity:

    Matt Kendall
    National Oceanic and Atmospheric Administration (NOAA), National Ocean Service (NOS), National Centers for Coastal Ocean Science (NCCOS), Center for Coastal Monitoring and Assessment (CCMA), Biogeography Program
    1305 East-West Highway
    Silver Spring, MD 20910

    301-713-3028 (voice)
    301-713-4388 (FAX)

    Date: 2011 (process 2 of 2)
    Metadata imported.

  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?

    To assess the thematic accuracy of the sonar portion of the maps, an independent field data set originally collected for a fishery assessment, was made available by scientists from the Department of Marine and Wildlife Resources in American Samoa (R. Tulafono, D. Ochavillo, M. Sabater, E. Simonsen, E. Schuster, T. Letalie). Each site consisted of GPS coordinates and several minutes of video data of the seafloor. Useable data were acquired for 77 points and compared to the attributes of the map polygons at each site to check thematic accuracy. A statistical analysis that generated a Tau statistic was preformed. The Tau statistic for the major classes exceeded 0.94 and for detailed classes exceeded 0.93. Overall thematic accuracy was established as 97.4% and 93.5% for the major and detailed structure classes respectively. A separate accuracy assessment was conducted for the shallow water-IKONOS based portion of the map that yielded similar results.

  2. How accurate are the geographic locations?

    Horizontal accuracy of the benthic maps is inherited from the source imagery. For example, RMS from digitized output based on IKONOS was determined using the ESRI RMEer2 extension and shown to be <1m when conducted at 1:6000 scale.

  3. How accurate are the heights or depths?

  4. Where are the gaps in the data? What is missing?

    Delineation of all habitat boundaries was conducted with the image scale at 1:6,000 for IKONOS and 1:10,000 for sonar. The minimum mapping unit (MMU) for identifying habitats or features was 1 acre.

  5. How consistent are the relationships among the observations, including topology?

    All mapping was conducted from sonar and orthorectified IKONOS satellite imagery. IKONOS satellite imagery was corrected for atmospheric and water column effects, color balanced, pan sharpened and deglinted. During the digitizing process, image stretches and manipulating image contrast, brightness and color balance were performed in the ArcView Image Analysis Extension to enhance features in the processed imagery. Sonar imagery and derived datasets were downloaded from <http://www.soest.hawaii.edu/pibhmc/>.

    Sonar based maps were edge matched to the IKONOS based maps and GIS topologic quality was established by executing ArcView extension routines that check for: overlapping polygons, multipart polygons, sliver polygons and void polygons. Additionally checks for adjacent polygons with the same habitat attributes were completed. All errors were identified and corrected. This file is believed to be logically consistent.


How can someone get a copy of the data set?

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

Access_Constraints: None
Use_Constraints: Not for navigation

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

    National Oceanic and Atmospheric Administration (NOAA), National Ocean Service (NOS), National Centers for Coastal Ocean Science (NCCOS), Center for Coastal Monitoring and Assessment (CCMA), Biogeography Program
    Biogeography Branch, Marine Biologist
    1305 East West Highway
    Silver Spring, MD 20910

    301-713-3028 (voice)
    301-713-4384 (FAX)
    matt.kendall@noaa.gov

    Hours_of_Service: 0800 - 1700, Monday to Friday, EST
  2. What's the catalog number I need to order this data set?

    Downloadable Data

  3. What legal disclaimers am I supposed to read?

    The National Oceanic and Atmospheric Administration (NOAA) National Centers for Coastal Ocean Science (NCCOS) produced this data CD-ROM. NCCOS Biogeography Program does not guarantee the accuracy of the geographic features or attributes. Please see the metadata records for each data set for complete information on the source, limitations, and proper use.

  4. How can I download or order the data?

  5. Is there some other way to get the data?

    Contact NOAA for distribution options (see Distributor). All maps of American Samoa prepared during this tenure are incorporated into this metadata summary.


Who wrote the metadata?

Dates:
Last modified: 16-Sep-2014
Last Reviewed: 18-May-2012
Metadata author:
National Oceanic and Atmospheric Administration (NOAA), National Ocean Service (NOS), National Centers for Coastal Ocean Science (NCCOS), Center for Coastal Monitoring and Assessment (CCMA), Biogeography Program
1305 East West Highway
Silver Spring, MD 20910

301-713-3028 (voice)
301-713-4384 (FAX)
matt.kendall@noaa.gov

Hours_of_Service: 0800 - 1700, Monday to Friday, EST
Metadata standard:
FGDC Content Standards for Digital Geospatial Metadata (FGDC-STD-001-1998)


Generated by mp version 2.9.13 on Wed Sep 17 10:42:41 2014