Identification_Information: Citation: Citation_Information: Originator: Pacific Islands Benthic Habitat Mapping Center (PIBHMC), Coral Reef Ecosystem Division (CRED), Pacific Islands Fisheries Science Center (PIFSC), National Marine Fisheries Service (NMFS), National Oceanic and Atmospheric Administration (NOAA) Publication_Date: 20110729 Title: Preliminary hard and soft bottom seafloor substrate map (5m grid) derived from an unsupervised classification of gridded backscatter and bathymetry derivatives at Rose Atoll Lagoon, Territory of American Samoa, USA. Geospatial_Data_Presentation_Form: digital data Online_Linkage: http://www.soest.hawaii.edu/pibhmc/pibhmc_amsamoa_rose_geomorph.htm Online_Linkage: http://www.soest.hawaii.edu/pibhmc/pibhmc_amsamoa_rose_geomorph.htm#substrate5m Description: Abstract: Preliminary hard and soft seafloor substrate map derived from an unsupervised classification of multibeam backscatter and bathymetry derivatives at Rose Atoll Lagoon, Territory of American Samoa, USA. The dataset was created from gridded (5 m cell size) multibeam bathymetry derivatives collected aboard R/V AHI; 2 scales of bathymetric variance and bathymetric rugosity, and from multibeam backscatter. Backscatter data were from a 240 kHz Reson 8101 sonar, gridded at 5 m. Very limited seafloor photographs for groundtruthing are available for Rose Atoll and therefore no supervised classification was performed and we are unable to visually or empirically evaluate the accuracy of the unsupervised classification seafloor substrate map. However, in locations such French Frigate Shoals, NWHI and Tutuila, American Samoa, where ground truth data are available, the unsupervised classification method is a robust predictor of substrate type in similar depth ranges and seafloor environments. Since groundtruthing was not used to validate the unsupervised classification at Rose Atoll Lagoon extreme caution should be used when examining these data to locate habitat of biological significance. The map should be used in conjunction with bathymetric derivatives such as rugosity, slope, and Bathymetric Position Index (BPI). Purpose: The hard and soft seafloor map is being used to improve sampling techniques for long-term ecosystem monitoring, to guide future ground-truthing operations and to identify coral-rich and species specific environments. This is a preliminary product and the methods used to generate the map are currently being evaluated for their accuracy. Supplemental_Information: Gridded multibeam data were collected 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 process for deriving the 5-m gridded multibeam bathymetry is described in Rose_5m.asc.txt, available on www.soest.hawaii.edu/pibhmc. The resulting grid (rose_5m.grd) was clipped using the ESRI ArcToolbox tool 'Extract by Mask' leaving only the multibeam data collected within the lagoon and excluding the narrow band of data around the upper slopes of the atoll. Classification was carried out just for this lagoon area, as classification using the full multibeam dataset was heavily affected by artifacts within this narrow band of data. The process for deriving the gridded multibeam backscatter is described in rose-8101-bs-1m.grd.txt. These data are gridded at 1m. Prior to classification the backscatter data were re-gridded at 5m, using the resample tool in the Arc Toolbox. The rugosity data used in this classification is also available on the same website, metadata describing the process of producing the rugosity grid is described in Rose_5m_rugosity.txt. The bathymetric variance grids were generated for use in the classification process and are not served separately. See the process description portion of this document for additional informaiton about how the variance and unsupervised layers were derived. A second classification was carried out using data collected on the slopes surrounding the atoll, and these are served separately on www.soest.hawaii.edu/pibhmc. Metadata for this second classification product is described in Rose_40m_hardsoft.txt. Time_Period_of_Content: Time_Period_Information: Range_of_Dates/Times: Beginning_Date: 20060210 Ending_Date: 20060313 Currentness_Reference: ground condition Status: Progress: Complete Maintenance_and_Update_Frequency: As needed Spatial_Domain: Bounding_Coordinates: West_Bounding_Coordinate: -168.176635 East_Bounding_Coordinate: -168.131605 North_Bounding_Coordinate: -14.525078 South_Bounding_Coordinate: -14.563367 Keywords: Theme: Theme_Keyword_Thesaurus: CRCP Project Theme_Keyword: Benthic Habitat Mapping and Characterization in the Pacific Islands Region Theme_Keyword: 467 Theme: Theme_Keyword_Thesaurus: CoRIS Theme Thesaurus Theme_Keyword: EARTH SCIENCE > Oceans > Coastal Processes > Coral Reefs > Coral Reef Ecology > Habitats Theme_Keyword: EARTH SCIENCE > Oceans > Coastal Processes > Coral Reefs > Coral Reef Ecology > Rugosity Theme_Keyword: EARTH SCIENCE > Biosphere > Zoology > Corals > Reef Monitoring and Assessment > Mapping Theme_Keyword: EARTH SCIENCE > Biosphere > Zoology > Corals > Reef Monitoring and Assessment > Mapping > geomorphology Mapping Theme_Keyword: EARTH SCIENCE > Biosphere > Zoology > Corals > Reef Monitoring and Assessment > Mapping > Habitat Mapping 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 Place: Place_Keyword_Thesaurus: CoRIS Place Thesaurus Place_Keyword: OCEAN BASIN > Pacific Ocean > American Samoa > Rose Atoll (14S168W0001) Place_Keyword: COUNTRY/TERRITORY > United States of America > American Samoa > American Samoa > Rose Atoll (14S168W0001) Place: Place_Keyword_Thesaurus: CoRIS Region Place_Keyword: AmSam 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) and School of Ocean and Earth Science and Technology (SOEST), University of Hawaii 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), National Marine Fisheries Service (NMFS), National Oceanic and Atmospheric Administration (NOAA) Contact_Address: Address_Type: mailing and physical address Address: NOAA IRC Address: NMFS/PIFSC/CRED Address: 1845 WASP Blvd., Building 176 City: Honolulu State_or_Province: HI Postal_Code: 96818 Contact_Voice_Telephone: 808 725-5360 Contact_Facsimile_Telephone: 808 725-5429 Contact_Electronic_Mail_Address: nmfs.pic.credinfo@noaa.gov Contact_Instructions: e-mail preferred Browse_Graphic: Browse_Graphic_File_Name: http://www.soest.hawaii.edu/pibhmc/amsamoa_images/Rose_5m_hardsoft_440.jpg Browse_Graphic_File_Description: Hard and Soft Seafloor Substrate Browse_Graphic_File_Type: JPEG, PDF Data_Set_Credit: PIBHMC, CRED, PIFSC, NOAA, and JIMAR Security_Information: Security_Classification_System: Not applicable Security_Classification: Unclassified Security_Handling_Description: Not applicable 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 (SPS) Horizontal position accuracy: 25 meters Vertical_Positional_Accuracy: Vertical_Positional_Accuracy_Report: 1 m Range resolution of sonar ~1.25 cm Raw sounding resolution: Variable Vertical accuracy of gridded product: 1% of water depth Lineage: Process_Step: Process_Description: Processing steps used to generate the backscatter, bathymetry, and bathymetric rugosity grids used in the unsupervised classification process are described in their own metadata that can be found at www.soest.hawaii.edu/pibhmc. Bathymetric variance was calculated from the 5 m multibeam bathymetry in a two-step process using ArcMap Version 9.2. The first step involved calculating the standard deviation of the bathymetry layer using the Neighborhood Statistic tool from the Spatial Analyst pull-down menu in ArcMap Version 9.2. Rectangular neighborhood settings were set to a height and width of 3 grid cells to create a small-scale variance layer. The standard deviation output was then squared using the ArcMap Raster Calculater tool. A large-scale variance layer was also generated using a rectangular neighborhood height and width of 5 grid cells. The fine-scale variance is useful for defining small features that may indicate the presence of sediment ripples or possible coral-rich areas whereas the large-scale variance is useful for defining seafloor ridges, pinnacles, and significant changes in slope. Bathymetric variance proved to be a useful tool in previous efforts to map seafloor habitats by Dartnell and Gardner (2004). Their publication can be downloaded from www.soest.hawaii.edu/pibhmc/pibhmc_documentation.htm. Bathymetric rugosity was calculated using the ArcGIS Benthic Terrain Modeler (D.J. Wright et al., 2005) accessible at http://www.csc.noaa.gov/digitalcoast/tools/btm/index.html. The layers were then opened as ESRI GRIDS in the image processing software package ENVI (Environment for Visualizing Images) Version 4.3. A multi-band images were then created with the backscatter, small- and large-scale variance, and rugosity. A mask was also created in ENVI for the dataset. Image classification was performed on the multi-band image using the K-Means unsupervised classification method, which calculates initial class means evenly distributed in the data space and then iteratively clusters the pixels into the nearest class using a minimum distance technique. More information about K-Means algorithm can be found in the ENVI documentation available at www.ittvis.com/envi/. The number of classes was set to two and all other options were set to default. Class color mapping was performed on the resulting classified images. The substrate types of hard and soft were assigned based on a visual interpretation of backscatter intensity and corresponding classes. Process_Date: 20110221 Spatial_Data_Organization_Information: Direct_Spatial_Reference_Method: Raster Raster_Object_Information: Raster_Object_Type: Grid Cell Row_Count: 835 Column_Count: 917 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: -2 Transverse_Mercator: Scale_Factor_at_Central_Meridian: 0.9996 Longitude_of_Central_Meridian: -171 Latitude_of_Projection_Origin: 0 False_Easting: 500000 False_Northing: 10000000 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 Vertical_Coordinate_System_Definition: Depth_System_Definition: Depth_Datum_Name: mean lower low water Depth_Resolution: 0.01 Depth_Distance_Units: meters Depth_Encoding_Method: Attribute Values Entity_and_Attribute_Information: Overview_Description: Entity_and_Attribute_Overview: none Entity_and_Attribute_Detail_Citation: none Distribution_Information: Distributor: 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), National Marine Fisheries Service (NMFS), National Oceanic and Atmospheric Administration (NOAA) Contact_Address: Address_Type: mailing and physical address Address: NOAA IRC Address: NMFS/PIFSC/CRED Address: 1845 WASP Blvd., Building 176 City: Honolulu State_or_Province: HI Postal_Code: 96818 Contact_Voice_Telephone: 808 725-5360 Contact_Facsimile_Telephone: 808 725-5429 Contact_Electronic_Mail_Address: nmfs.pic.credinfo@noaa.gov Contact_Instructions: e-mail preferred 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: ftp://ftp.soest.hawaii.edu/pibhmc/website/data/amsamoa/benthichabitatlayers/Rose_5m_HardSoft.zip Fees: None Metadata_Reference_Information: Metadata_Date: 20170124 Metadata_Review_Date: 20110830 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), National Marine Fisheries Service (NMFS), National Oceanic and Atmospheric Administration (NOAA) Contact_Address: Address_Type: mailing and physical address Address: NOAA IRC Address: NMFS/PIFSC/CRED Address: 1845 WASP Blvd., Building 176 City: Honolulu State_or_Province: HI Postal_Code: 96818 Contact_Voice_Telephone: 808 725-5360 Contact_Facsimile_Telephone: 808 725-5429 Contact_Electronic_Mail_Address: nmfs.pic.credinfo@noaa.gov 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 CoRIS: CoRIS_ID: 20110830065050 CoRIS_Children: None CoRIS_Beginning_Date: 20060210 CoRIS_Ending_Date: 20060313 CoRIS_Metadata_Link: https://www.coris.noaa.gov/metadata/records/html/rose_5m_hardsoft.html CoRIS_Tracking_ID: 6351