Identification_Information: Citation: Citation_Information: Originator:Originator: NOAA Pacific Island Fisheries Science Center Coral Reef Ecosystem Division Pacific Islands Benthic Habitat Mapping Center Publication_Date: 200703 Title: Simrad em120 multibeam backscatter data from portions of the banktop and bank edge environments at Maro Reef, Hawaii, USA Geospatial_Data_Presentation_Form: digital data Online_Linkage: http://www.soest.hawaii.edu/pibhmc/ Description: Abstract: Multibeam backscatter imagery extracted from gridded bathymetry of Maro Reef, Northwestern Hawaiian Islands, USA. These data provide coverage between 20 and 5000 meters. The backscatter dataset includes data collected using Simrad EM300, Simrad EM3002d, Simrad EM120, and Reson 8101 multibeam sonars. The sonars frequencies are 30 kHz, 300 kHz, 12 kHz, and 240 kHz respectively and the backscatter data from each sonar are processed and gridded separately. These metadata are for the 30 m grid cell size Simrad em120 multibeam backscatter data only. Purpose: This ASCII file of backscatter imagery was created using data gathered from multibeam soundings for use as a planning and reference document. The data are also being used for benthic habitat mapping, for locating Essential Fish Habitat, and for studying geologic features of the area. Refer to supplemental information for description of instrument and survey. Supplemental_Information: Multibeam data were collected aboard the R/V Kilo Moana, a 186’ United States Navy owned research vessel operated by the University of Hawaii. The R/V Kilo Moana's survey sensors include a 12 kHz Simrad EM120 sonar and a 95 kHz Simrad EM1002 sonar, which provide bathymetry and imagery data, a TSS/Applanix POS/MV Model 320, which measures position, velocity, attitude and heading, and a Sippican MK-21/PC based XBT system plus a Seabird SBE 9/11 CTD both of which measured sound velocity profiles. Specific equipment configurations are documented in metadata from cruise: KM0206. These metadata can be accessed at: http://www.soest.hawaii.edu/pibhmc/pibhmc_cruise-catalog.htm. Time_Period_of_Content: Time_Period_Information: Range of Dates/Times: Beginning_Date: 20021022 Ending_Date: 20021116 Currentness_Reference: ground condition Status: Progress: Complete Maintenance_and_Update_Frequency: As needed Spatial_Domain: Bounding_Coordinates: West_Bounding_Coordinate: -171.372 East_Bounding_Coordinate: -170.022 North_Bounding_Coordinate: 25.754 South_Bounding_Coordinate: 24.987 Keywords: Theme: Theme_Keyword_Thesaurus: CoRIS Theme Thesaurus Version 1.0 Theme_Keyword: EARTH SCIENCE > Oceans > Bathymetry/Seafloor Topography > Backscatter Theme_Keyword: Acoustic Imagery Theme_Keyword: Multibeam Backscatter Theme_Keyword: Backscatter Place: Place_Keyword_Thesaurus: None Place_Keyword: Maro Reef Place_Keyword: Hawaii Place_Keyword: Northwestern Hawaiian Islands Place_Keyword: United States of America Place: Place_Keyword_Thesaurus: CoRIS Place Thesaurus Version 1.0 Place_Keyword: OCEAN BASIN > Pacific Ocean > Central Pacific Ocean > Hawaiian Islands > Maro Reef 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 and the Joint Institute for Marine and Atmospheric Research (JIMAR) University of Hawaii as the sources of this information. 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_File_Name: maro-bs.jpg Browse_Graphic_File_Name: maro-em120-bs.jpg Browse_Graphic_File_Description: Multibeam Backscatter Browse_Graphic_File_Description: Acoustic Imagery Browse_Graphic_File_Type: JPEG Data_Set_Credit: PIBHMC, CRED, PIFSC, NOAA and JIMAR Native_Data_Set_Environment: Arc ASCII file created using MB-System and GMT software in a LINUX environment 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: Multibeam data were collected using Simrad Neptune software. Multibeam data were processed using MB-System, an open source software package for the processing and display of bathymetry and backscatter imagery data. The data were destriped using mbfilter, a grazing angle correction was calculated and appplied to the data using mbbackangleold and mbanglecorrect, and the data were gridded using mbmosaic. ASCII files were created from netCDF grids using the Generic Mapping Tools (GMT). More information about MB-System and GMT can be found at: www.ldeo.columbia.edu/res/pi/MB-System/ www.soest.hawaii.edu/gmt/ Process_Date: 20021101 Spatial_Data_Organization_Information: Direct_Spatial_Reference_Method: Raster Raster_Object_Information: Raster_Object_Type: Grid Cell Row_Count: 2841 Column_Count: 4519 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: 30 Ordinate_Resolution: 30 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: 0.9996 Longitude_of_Central_Meridian: -171 Latitude_of_Projection_Origin: 0 False_Easting: 500000 False_Northing: 0 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 meters Depth_Distance_Units: meters Depth_Encoding_Method: Attribute values Entity_and_Attribute_Information: Overview_Description: Entity_and_Attribute_Overview: Sidescan data within a Simrad file are arranged as small sequences of intensity values, one sequence per beam per ping. The intensity values represent the amplitude of echo returns to the sensor and can be related to seabed roughness. 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), 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, .asc Format_Information_Content: Arc ASCII can be converted to Arc Raster using ArcToolbox Conversion Tools. File_Decompression_Technique: none Transfer_Size: Variable 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: 20070312 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