Identification_Information: Citation: Citation_Information: Originator: Benthic Habitat Mapping Group, CRED, PIFSC, NOAA Publication_Date: 20100607 Title: Mosaic of gridded multibeam bathymetry and bathymetry derived from multispectral IKONOS satellite imagery of Rose Atoll, American Samoa, USA Geospatial_Data_Presentation_Form: raster digital data Online_Linkage: http://www.soest.hawaii.edu/pibhmc Online_Linkage: http://www.soest.hawaii.edu/pibhmc/development/pibhmc_amsamoa_rose_bathy.htm Description: Abstract: Gridded multibeam bathymetry is integrated with bathymetry derived from multispectral IKONOS satellite data. Gridded (5 m cell size) multibeam bathymetry were collected aboard the R/V AHI (Acoustic Habitat Investigator). Bathymetry values shallower than 25 m were derived from multispectral IKONOS satellite image by analyzing the relative attenuation of blue and green spectral radiance as a function of depth. A multiple linear regression analysis of linearized blue and green band spectral values against multibeam depths determined the variables of y-intercept, blue slope and green slope values. Variables were then used in multivariate slope intercept formula to derive depth. Variables were adjusted to improve the statistical accuracy and spatial coverage of the final derived bathymetry product. Digital image processing to derive depths conducted with the ENVI 4.5 software program while data editing and integration was performed using ArcGIS 9.3. This dataset is for the bank and lagoon environment of Rose Atoll, American Samoa, USA. Purpose: The data were derived in support of NOAA 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 integration of derived bathymetry data provides a GIS layer with expanded spatial coverage that may be used for benthic and essential fish habitat characterization, and for the study of geologic features. By combining the dataset with other bathymetry, backscatter, derivatives, and in situ data, they collectively compose benthic habitat maps designed to be used to understand and predict shallow depth (0m to 150m) benthic habitats for organisms that inhabit coral reef ecosystems. Supplemental_Information: Original IKONOS imagery was purchased to support the Pacific Islands Geographic Information System (GIS) project and National Ocean Service's (NOS) coral mapping activities. Orthographically corrected IKONOS Imagery was provided by NOAA's National Centers for Coastal Ocean Science, Center for Coastal Monitoring and Assessment. The metadata for this IKONOS imagery is documented in the original product metadata, po_87351_metadata_rose (http://www.soest.hawaii.edu/pibhmc/) 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 metadata for the bathymetry is documented in the product metadata, Rose_5m.asc.txt. http://www.soest.hawaii.edu/pibhmc/pibhmc_amsamoa_rose.htm Time_Period_of_Content: Time_Period_Information: Range_of_Dates/Times: Beginning_Date: 20020305 Ending_Date: 20060313 Currentness_Reference: ground condition Status: Progress: Complete Maintenance_and_Update_Frequency: As needed Spatial_Domain: Bounding_Coordinates: West_Bounding_Coordinate: -168.173489 East_Bounding_Coordinate: -168.136652 North_Bounding_Coordinate: -14.527710 South_Bounding_Coordinate: -14.561023 Keywords: Theme: Theme_Keyword_Thesaurus: CoRIS Theme Keyword Thesaurus Theme_Keyword: EARTH SCIENCE > Biosphere > Zoology > Corals > Reef Monitoring and Assessment > Remote Sensing > Satellite (digital scans) > IKONOS Theme_Keyword: EARTH SCIENCE > Biosphere > Aquatic Habitat > Reef Habitat > Description Theme_Keyword: EARTH SCIENCE > Oceans > Bathymetry/Seafloor Topography > Bathymetry Theme_Keyword: EARTH SCIENCE > Oceans > Bathymetry/Seafloor Topography > Water Depth 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) Access_Constraints: None Use_Constraints: These data are not to be used for navigation purposes. Please acknowledge NOAA Pacific Islands Fisheries Science Center, the Joint Institute for Marine and Atmospheric Research (JIMAR) University of Hawaii and Davey Jones Locker GIS Laboratory Oregon State University 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/amsamoa/bathymetry/Rose_bathymetry_mb&IKONOS.jpg Browse_Graphic_File_Description: Gridded Bathymetry Browse_Graphic_File_Type: JPEG Data_Set_Credit: NOAA PIFSC CRED, the Pacific Islands Benthic Habitat Mapping Center and Davey Jones Locker GIS Laboratory Oregon State University Native_Data_Set_Environment: ArcGIS ASCII file or ArcGIS Grid file, bathymetry derived from 4x4m multispectral satellite imagery (IKONOS) using ENVI 4.5, multibeam and derived bathymetry were integrated using ArcGIS 9.3 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 sonar product: ~ 1% of water depth Vertical accuracy of derived bathymetry product: 5 meter range Lineage: Process_Step: Process_Date: 20100601 Process_Description: Multiple tools in ENVI 4.5 were used to complete the following processing steps: Data conversion from digital number to radiance, correction for atmosphere and water surface reflection, linearization of spectral decay as function of depth, masking of non-applicable values, and bathymetric derivation using variables from multiple linear regression analysis. Multiple tools in ArcGIS 9.3 were used for dataset integration and to extract values for the multiple linear regression analysis and subsequent error analyses. The statistics program S-Plus was used for the multiple linear regression analysis to provide original variables for depth derivation. The multivariate slope intercept formula used to derive depth was Depth=Yint+(Mblue)(Xblue)+(Mgreen)(Xgreen). Fourteen derived products from the image rose_msi_rat_final (Rose351) were integrated to expand spatial coverage. This image was provided in TIFF format. The original MLR variables for Rose351 were Yint=13.2711, Mblue=1.8847, and Mgreen=11.2034. The product derived from these variables (Rose351_DB) was mosaiced with thirteen additional products derived using increasingly reduced Y-intercept values as follows: Yint=12.2711 (Rose351_DB1), Yint=11.2711 (Rose351_DB2), Yint=10.2711 (Rose351_DB3), Yint=9.2711 (Rose351_DB4), Yint=8.2711 (Rose351_DB5), Yint=7.2711 (Rose351_DB6), Yint=6.2711 (Rose351_DB7), Yint=5.2711 (Rose351_DB8), Yint=4.2711 (Rose351_DB9), Yint=3.2711 (Rose351_DB10), Yint=2.2711 (Rose351_DB11), Yint=1.2711 (Rose351_DB12), Yint=0.2711 (Rose351_DB13). This was done to increase coverage in shallow areas. A detailed description of these processing steps is available at: http://oregonstate.edu/~hogrefek/Cookbook/Cookbook_042108.pdf An error analysis of each derived bathymetry grid used is available from PIBHMC upon request. This mosaiced derived bathymetry product (rose_dball2) was then integrated with the multibeam sonar data, with sonar data prioritized over derived data, to create the final product (rose_5m_dbmb), through the following steps. Initially, grdmath, a Generic Mapping Tools (GMT) algorithm that combines multiple grids, was used to combine the mosaicked derived bathymetry product (rose_dball2) with the gridded multibeam bathymetry (rose_5m). The AND operator was used to prioritize use of the multibeam grid over the derived bathymetry grid, where the two overlapped. The resulting product was found to have a noticeable artifact in the form of a marked step in depth on the bank top, where the derived bathymetry and multibeam bathymetry grids met. To avoid this problem, the final product was created by integrating the mosaic derived bathymetry product (rose_dball2) with an extracted subset of the multibeam data that only covered the inner lagoon. First, Fledermaus 3D Editor was used to extract xyz values from the multibeam data to create a subset covering the inner lagoon (rose_lagoon.xyz). The GMT nearneighbor algorithm was used to create a netCDF grid from the lagoon multibeam data. Secondly, xyz points were extracted from the derived bathymetry product (rose_dball2) using the Sample tool, available in ESRI ArcToolbox. The GMT nearneighbor algorithm was used to create a nearneighbor grid from these data. The two nearneighbor grids (one from the lagoon multibeam bathymetry and one from the mosaiced derived bathymetry product) were combined using grdmath. The AND operator was used to prioritize use of the multibeam grid over the derived bathymetry grid, where the two overlapped. The resulting grid (ros_5m_dbmb.nn.grd) was then converted to ASCII format using LINUX/UNIX commands in combination with GMT. (rose_5m_dmbm.asc). GMT is an open source collection of tools for manipulating geographic data sets. Additional information about GMT can be found at: www.soest.hawaii.edu/gmt 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: Planar_Coordinate_Information: Planar_Coordinate_Encoding_Method: row and column Coordinate_Representation: Abscissa_Resolution: 5.000000 Ordinate_Resolution: 5.000000 Planar_Distance_Units: meters Grid_Coordinate_System: Grid_Coordinate_System_Name: Universal Transverse Mercator Universal_Transverse_Mercator: UTM_Zone_Number: 2S 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 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: 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 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/development/pibhmc_amsamoa_rose_bathy.htm Fees: None Metadata_Reference_Information: Metadata_Date: 20100601 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