Identification_Information: Citation: Citation_Information: Originator: Hogrefe Natural Systems Analysis in collaboration with Davey Jones Locker GIS Laboratory, Oregon State Universtiy for Coral Reef Ecosystem Division, NOAA Pacific Islands Fisheries Science Center, Pacific Islands Benthic Habitat Mapping Center Publication_Date: 20081203 Title: Mosaic of gridded multibeam bathymetry and bathymetry derived from multispectral IKONOS satellite imagery of Ofu and Olosega Islands, Territory of American Samoa, USA Geospatial_Data_Presentation_Form: raster digital data Online_Linkage: http://soest.hawaii.edu/pibhmc Description: Abstract: Gridded multibeam bathymetry is integrated with bathymetry derived from multpectral IKONOS satellite data. Gridded (5 m cell size) multibeam bathymetry collected aboard NOAA Ship Hiialaka'i and R/V AHI. Bathymetry values shallower than 25 m were derived by gauging the reletive 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 depth determined the variables of y-intercept, blue slope and green slope values. Variables 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 4.3 software program while data editing and integration was performed using ArcGIS 9.3. This data set is for the shelf environment of Ofu and Olosega Islands, American Samoa. 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 with multibeam sonar 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: Gridded multibeam data were collected aboard the Hi'ialakai, a 218-ft. United States National Oceanographic and Atmospheric Administration (NOAA) research ship, and aboard the R/V AHI (Acoustic Habitat Investigator), a 25-ft. 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, ofuolo_5m.grd.txt. http://www.soest.hawaii.edu/pibhmc/pibhmc_amsamoa_ofu_bathy.htm 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_91074_metadata_manua, and the orthorectified product metadata, ofu_msi_metadata_2003. (http://www.soest.hawaii.edu/pibhmc/) Time_Period_of_Content: Time_Period_Information: Range_of_Dates/Times: Beginning_Date: 20020407 Ending_Date: 20040212 Currentness_Reference: ground condition Status: Progress: Complete Maintenance_and_Update_Frequency: As needed Spatial_Domain: Bounding_Coordinates: West_Bounding_Coordinate: -169.705274 East_Bounding_Coordinate: -169.583687 North_Bounding_Coordinate: -14.133505 South_Bounding_Coordinate: -14.203385 Keywords: Theme: Theme_Keyword_Thesaurus: CoRIS Theme Keyword Thesaurus 200806 Theme_Keyword: EARTH SCIENCE > Oceans > Bathymetry/Seafloor Topography > Bathymetry Theme: Theme_Keyword_Thesaurus: CoRIS Theme Keyword Thesaurus 200806 Theme_Keyword: EARTH SCIENCE > Oceans > Bathymetry/Seafloor Topography > Water Depth Theme: Theme_Keyword_Thesaurus: CoRIS Theme Keyword Thesaurus 200806 Theme_Keyword: EARTH SCIENCE > Biosphere > Zoology > Corals > Reef Monitoring and Assessment > Remote Sensing > Satellite (digital scans) > IKONOS Theme: Theme_Keyword_Thesaurus: None Theme_Keyword: Slope Theme_Keyword: Bathymetry Theme_Keyword: Multibeam sonar Place: Place_Keyword_Thesaurus: None Place_Keyword: Ofu Island Place_Keyword: Olosega Island Place_Keyword: American Samoa Place_Keyword: United States of America Place: Place_Keyword_Thesaurus: CoRIS Place Keywords by Ocean - Pacific Ocean April 2007 (without Great Barrier Reef) Place_Keyword: OCEAN BASIN > Pacific Ocean > Manu'a Group > Olosega Island (14S169W0014) Place_Keyword: OCEAN BASIN > Pacific Ocean > Manu'a Group > Ofu Island (14S169W0014) Place: Place_Keyword_Thesaurus: CoRIS Place Keywords by Country/Territory - Pacific Ocean November 2007 (without Great Barrier Reef) Place_Keyword: COUNTRY/TERRITORY > United States of America > American Samoa > American Samoa > Olosega Island (14S169W0014) Place_Keyword: COUNTRY/TERRITORY > United States of America > American Samoa > American Samoa > Ofu Island (14S169W0013) Place_Keyword: COUNTRY/TERRITORY > United States of America > Hawaii > Honolulu 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. Browse_Graphic: Browse_Graphic_File_Name: OO_DBMB_Mosaic.pdf Browse_Graphic_File_Description: Gridded Bathymetry Browse_Graphic_File_Type: PDF 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 4.3, 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: 20081201 Process_Description: Multiple tools in ENVI 4.3 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 statisitcs 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). Four derived products, two from the image manua_msi_001_rat (OO-01) and two from the image manua_msi_004_rat (OO-04) were integrated to expand coverage. The original MLR variables for OO-01 were Yint=0.3846, Mblue=-5.9154, and Mgreen=10.2817. The product derived from these variables (OO-01-DB) was mosaiced with the product derived using a reduced Y-intercept value of -1.6154 (OO-01-DB2) to increase coverage in shallow areas. Data from OO-01-DB replaced data from OO-01-DB2 during integration due to better statistical accuracy. The original MLR variables for OO-04 were Yint=2.7799, Mblue=-8.6960, and Mgreen=15.1653. The product derived from these variables (OO-04-DB) was mosaiced with the product derived using reduced linearized blue and green band slope values of -0.6960 and 7.1653 (OO-04-DB5) to increase coverage in shallow areas. Data from OO-04-DB replaced data from OO-04-DB5 during integration due to better statistical accuracy. The derived bathymetry mosaics from each image were in turn mosaiced giving the data from image OO-01 priority due to its better spatial coverage in areas of shallow depth. This mosaiced derived bathymetry product (OO_DBAll_mos3) was then integrated with the multibeam sonar data, with sonar data prioritized over derived data, to create the final product (OO_DBMB_mos4). A detailed description of all processing steps is available at: http://oregonstate.edu/~hogrefek/Cookbook/Cookbook_042108.pdf An error analysis of each derived bathymetry grid used is available upon request. Spatial_Data_Organization_Information: Direct_Spatial_Reference_Method: Raster Raster_Object_Information: Raster_Object_Type: Pixel Row_Count: 1531 Column_Count: 2616 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: -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 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: NOAA PIFSC CRED PIBHMC and DJLab OSU Contact_Person: Kyle Hogrefe Contact_Address: Address_Type: mailing and physical address Address: 104 Wilkinson Hall, Oregon State University City: Corvallis State_or_Province: Oregon Postal_Code: 97331 Country: USA Contact_Voice_Telephone: 541-737-2397 Contact_Electronic_Mail_Address: hogrefek@geo.oregonstate.edu 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 Grid Format_Information_Content: Arc Grid can be opened directly using ArcMap or ArcCatalog. 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: 20081203 Metadata_Contact: Contact_Information: Contact_Person_Primary: Contact_Organization: NOAA PIFSC CRED PIBHMC and DJLab OSU Contact_Person: Kyle Hogrefe Contact_Address: Address_Type: mailing and physical address Address: 104 Wilkinson Hall, Oregon State University City: Corvallis State_or_Province: Oregon Postal_Code: 97331 Country: USA Contact_Voice_Telephone: 541-737-2397 Contact_Electronic_Mail_Address: hogrefek@geo.oregonstate.edu 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