Identification_Information:
  Citation:
    Citation_Information:
      Originator:
        Coral Reef Ecosystem Division, NOAA Pacific Islands Fisheries
        Science Center, Pacific Islands Benthic Habitat Mapping Center
      Publication_Date: 20080830
      Title:
        Bathymetric Position Index (BPI) Structures 5 m grid derived from gridded
        bathymetry of Tinian Island, Commonwealth of the Northern Mariana
        Islands (CNMI), USA.
      Geospatial_Data_Presentation_Form: raster digital data
      Online_Linkage: http://www.soest.hawaii.edu/pibhmc
  Description:
    Abstract:
      BPI Structures are derived from two scales of a focal mean
      analysis on bathymetry and slope. The grid is based on
      gridded (5 m cell size) multibeam bathymetry, collected aboard NOAA
      Ship Hi'ialakai and R/V AHI, and it was created using the Benthic
      Terrain Modeler (http://www.csc.noaa.gov/products/btm/). Cell values
      represent one of 14 classes in an index of seafloor terrains. This
      data set is for the shelf and slope environments of Tinian Island. As
      part of the southern islands in the Mariana Islands archipelago,
      Tinian has a shelf (above -100m) with escarpments that lead to broad
      flat areas without forming a deeper shelf. Conversely, the northern
      islands each have a shelf (above -60m), and most have a deep shelf
      (below -60m), with escarpments that lead outside of the coverage area.
    Purpose:
      The data were derived in support of Coral Reef Conservation
      Program goals. Goal 1 is to map all U.S. Coral Reef Ecosystems.
      This data set specifically addresses Objective 1 and 4: to develop
      high-resolution benthic maps and to characterize priority deep
      water reefs and associated habitats.  This derivative of
      bathymetry provides a GIS layer that may be used for benthic and
      essential fish habitat characterization, and for the study of
      geologic features. By combining the dataset with bathymetry,
      backscatter, other derivatives, and in situ data, they
      collectively compose benthic habitat maps which are designed to
      be used to understand and predict moderate depth (~20m to 400m)
      benthic habitats for different organisms that inhabit coral
      reef ecosystems.
    Supplemental_Information:
      Gridded multibeam data were collected aboard the Hi'ialakai, a
      218' United States National Oceanographic and Atmospheric
      Administration (NOAA) research ship, and aboard the R/V AHI
      (Acoustic Habitat Investigator), a 25' survey launch owned and
      operated by the NOAA Pacific Islands Fisheries Science Center in
      Honolulu, HI.  The metadata for the bathymetry is documented in
      the product metadata, tinian_5m.txt.
      (http://www.soest.hawaii.edu/pibhmc/pibhmc_cnmi_bathy.htm)
      References:
      Lundblad et al., 2006, A benthic terrain classification scheme for
      American Samoa, Marine Geodesy, 29(2):89 - 111.
      http://www.csc.noaa.gov/products/btm/
      The terrestrial elevation data shown in the map for this data set are
      SRTM Finished 3 arc sec Shaded Relief. They were collected during
      NASA's Shuttle Radar Topograph Mission (SRTM). For more information
      on the mission, go to:
      http://www2.jpl.nasa.gov/srtm/faq.html#data. The data are available
      from the United States Geological Survey (USGS) as reformatted
      elevation data that are consistent with other Digital Elevation Models.
  Time_Period_of_Content:
    Time_Period_Information:
      Range_of_Dates/Times:
        Beginning_Date: 20030821
        Ending_Date: 20070608
    Currentness_Reference: ground condition
  Status:
    Progress: Complete
    Maintenance_and_Update_Frequency: As needed
  Spatial_Domain:
    Bounding_Coordinates:
      West_Bounding_Coordinate: 145.502
      East_Bounding_Coordinate: 145.756
      North_Bounding_Coordinate: 15.123
      South_Bounding_Coordinate: 14.803
  Keywords:
    Theme:
      Theme_Keyword_Thesaurus: CoRIS Discovery Thesaurus
      Theme_Keyword: Geographic Information > Habitats
    Theme:
      Theme_Keyword_Thesaurus: ISO 19115 Topic Category
      Theme_Keyword: imageryBaseMapsEarthCover
      Theme_Keyword: 010
    Theme:
      Theme_Keyword_Thesaurus: CoRIS Theme Thesaurus
      Theme_Keyword: EARTH SCIENCE > Oceans > Bathymetry/Seafloor Topography > Bathymetric Position Index Structures
      Theme_Keyword: EARTH SCIENCE > Biosphere > Zoology > Corals > Reef Monitoring and Assessment > Mapping > geomorphology Mapping
    Theme:
      Theme_Keyword_Thesaurus: None
      Theme_Keyword: Bathymetric Position Index Structures
      Theme_Keyword: Bathymetry
      Theme_Keyword: Multibeam sonar
    Place:
      Place_Keyword_Thesaurus: None
      Place_Keyword: Tinian Island
      Place_Keyword: Aguijan Island
      Place_Keyword: Tatsumi Bank
      Place_Keyword: Commonwealth of the Northern Mariana Islands
      Place_Keyword: United State of America
    Place:
      Place_Keyword_Thesaurus: CoRIS Place Thesaurus
      Place_Keyword: OCEAN BASIN > Pacific Ocean > Western Pacific Ocean > Tinian Island Reefs > Tinian Island (14N145E0005)
      Place_Keyword: COUNTRY/TERRITORY > Northern Mariana Islands > Tinian > Tinian Island (14N145E0005)
  Access_Constraints: None
  Use_Constraints:
    These data are not to be used for navigation
    purposes. Please acknowledge the NOAA Pacific Islands Fisheries
    Science Center (PIFSC) Coral Reef Ecosystem Division (CRED) and
    the Pacific Islands Benthic Habitat Mapping Center (PIBHMC), and
    the Joint Institute for Marine and Atmospheric Research (JIMAR)
    as the sources of this information.
  Point_of_Contact: 
    Contact_Information: 
      Contact_Organization_Primary: 
        Contact_Organization: Pacific Islands Benthic Habitat Mapping Center (PIBHMC), Coral Reef Ecosystem Division (CRED), 
          Pacific Islands Fisheries Science Center (PIFSC), NOAA National Marine Fisheries Service (NMFS)
      Contact_Address: 
        Address_Type: mailing and physical
        Address: 1680 East-West Road POST 833
        City: Honolulu
        State_or_Province: HI
        Postal_Code: 96822
        Country: USA
      Contact_Voice_Telephone: 808-956-5239
      Contact_Electronic_Mail_Address: pibhmc@soest.hawaii.edu
      Contact_Instructions: e-mail preferred
  Browse_Graphic:
    Browse_Graphic_File_Name: ftp://ftp.soest.hawaii.edu/pibhmc/website/data/cnmi-guam/benthichabitatlayers/tinian_5m_BPIstructures.jpg
    Browse_Graphic_File_Description: Gridded Bathymetry Derivative
    Browse_Graphic_File_Type: JPG
  Data_Set_Credit: NOAA PIFSC CRED PIBHMC and JIMAR
  Native_Data_Set_Environment:
    ArcGIS ASCII file, derived from bathymetry and
    slope in ArcGIS 9.3 (Spatial Analyst and Benthic Terrain Modeler)
Data_Quality_Information:
  Attribute_Accuracy:
    Attribute_Accuracy_Report:
      Data are collected for resource
      management and research purposes and are tested for
      internal consistency; however, no effort is made to compare
      these data to external references or to other published data.
  Logical_Consistency_Report:
    These data are believed to be logically
    consistent though no tests were performed
  Completeness_Report: Complete
  Positional_Accuracy:
    Horizontal_Positional_Accuracy:
      Horizontal_Positional_Accuracy_Report:
        Horizontal positioning system: GPS C/A
        Horizontal position accuracy: 25 meters
    Vertical_Positional_Accuracy:
      Vertical_Positional_Accuracy_Report:
        Range resolution of sonar: varies with depth
        Raw sounding resolution: varies with depth
        Vertical accuracy of gridded product ~ 1% of water depth
  Lineage:
    Process_Step:
      Process_Description:
        Bathymetric Position Index Structures were derived from the gridded
        multibeam bathymetry (tinian_5m) using the Benthic Terrain Modeler
        (BTM). The BTM (written for ArcGIS 8.x or 9.x) may be downloaded from
        http://dusk2.geo.orst.edu/djl/samoa/tools.html.
        BPI Structures are derived from two scales of a focal mean analysis
        on bathymetry and slope. After testing combinations, two
        scales of bpi (50 & 250) were chosen for Tinian Island. Three fine
        scale factors (20, 30, and 50) and two broad scale factors
        (250 and 500) were tested in different combinations.  After measuring
        many of the bathymetric features that indicate possible reef structures
        when overlaid on the hillshade, initially the values of 250 and 20 were
        used (also after Lundblad et al. 2006; see Supplemental_Information).
        However, after running the Benthic Terrain Modeler (BTM), it was
        apparent that most of the fine scale structures were hard to identify in
        the classification. Therefore, the other scales of BPI grids were
        created and used in the Terrain Classification Builder (part of the BTM)
        to create multiple structure and zone grids. The combination of
        20 (or 30) and 250 brought out those fine scale structures, including
        the broad crests, which are very important in coral reef environments.
        However, the fine scale factor of 50 defined the fine scale structures
        as more continuous features and cancelled out a lot of the noise that
        was falsely defined by using 20 or 30. Additionally, three ranges of
        slope define flats, slopes, and near vertical: x < 5; 5 < x < 70;
        x > 70.  Depth bounds separated broad flat (< -100m) structures from the
        shelf (0 to -100m) environments. The deep shelf class was excluded for
        Tinian since there is not a step in the bathymetry offshore of Tinian,
        rather a gradual escarpment with broad flat areas. The depths were based on
        the bathymetric drop off outside the harbor and at the edge of Tatsumi Bank.
      Process_Date: 20080820
Spatial_Data_Organization_Information:
  Direct_Spatial_Reference_Method: Raster
  Raster_Object_Information:
    Raster_Object_Type: Grid Cell
    Row_Count: 7051
    Column_Count: 5423
    Vertical_Count: 1
Spatial_Reference_Information:
  Horizontal_Coordinate_System_Definition:
    Planar:
      Grid_Coordinate_System:
        Grid_Coordinate_System_Name: Universal Transverse Mercator
        Universal_Transverse_Mercator:
          UTM_Zone_Number: 55
          Transverse_Mercator:
            Scale_Factor_at_Central_Meridian: 0.9996
            Longitude_of_Central_Meridian: 147
            Latitude_of_Projection_Origin: 0
            False_Easting: 500000
            False_Northing: 0
      Planar_Coordinate_Information:
        Planar_Coordinate_Encoding_Method: row and column
        Coordinate_Representation:
          Abscissa_Resolution: 5
          Ordinate_Resolution: 5
        Planar_Distance_Units: meters
    Geodetic_Model:
      Horizontal_Datum_Name: D_WGS_1984
      Ellipsoid_Name: WGS_1984
      Semi-major_Axis: 6378137.000000
      Denominator_of_Flattening_Ratio: 298.257224
Distribution_Information:
  Distributor:

  Resource_Description: Downloadable Data
  Distribution_Liability:
    These data are not to be used for navigational purposes.
    NOAA makes no warranty regarding these data, expressed or implied,
    nor does the fact of distribution constitute such a warranty.
    NOAA cannot assume liability for any damages caused by any errors
    or omissions in these data, nor as a result of the failure of
    these data to function on a particular system.
  Standard_Order_Process:
    Digital_Form:
      Digital_Transfer_Information:
        Format_Name: Arc ASCII
        Format_Information_Content:
          Arc ASCII can be converted to Arc Raster
          using ArcToolbox Conversion Tools (ASCIItoRaster).
      Digital_Transfer_Option:
        Online_Option:
          Computer_Contact_Information:
            Network_Address:
              Network_Resource_Name: http://www.soest.hawaii.edu/pibhmc
    Fees: None
Metadata_Reference_Information:
  Metadata_Date: 20080830
  Metadata_Contact:
    Contact_Information: 
      Contact_Organization_Primary: 
        Contact_Organization: Pacific Islands Benthic Habitat Mapping Center (PIBHMC), Coral Reef Ecosystem Division (CRED), 
          Pacific Islands Fisheries Science Center (PIFSC), NOAA National Marine Fisheries Service (NMFS)
      Contact_Address: 
        Address_Type: mailing and physical
        Address: 1680 East-West Road POST 833
        City: Honolulu
        State_or_Province: HI
        Postal_Code: 96822
        Country: USA
      Contact_Voice_Telephone: 808-956-5239
      Contact_Electronic_Mail_Address: pibhmc@soest.hawaii.edu
      Contact_Instructions: e-mail preferred
  Metadata_Standard_Name: FGDC Content Standards for Digital Geospatial Metadata
  Metadata_Standard_Version: FGDC-STD-001-1998
  Metadata_Time_Convention: Universal Time
  Metadata_Access_Constraints: None
  Metadata_Use_Constraints: None