CRED 16M Multibeam backscatter at Tutuila, American Samoa, 2006

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Metadata:

Identification_Information:
Citation:
Citation_Information:
Originator:
NOAA Pacific Island Fisheries Science Center Coral Reef Ecosystem Division Pacific Islands Benthic Habitat Mapping Center
Publication_Date: 20070501
Title: CRED 16M Multibeam backscatter at Tutuila, American Samoa, 2006
Geospatial_Data_Presentation_Form: digital data
Online_Linkage: <http://www.soest.hawaii.edu/pibhmc>
Description:
Abstract:
Multibeam backscatter imagery extracted from gridded bathymetry of Tutuila, American Samoa, South Pacific. These data provide coverage between 20 and 5000 meters. The backscatter dataset includes data collected using Simrad EM3002d and Reson 8101 multibeam sonars. The sonars frequencies are 300 kHz and 240 kHz respectively and the backscatter data from each sonar are processed and gridded separately. These metadata are for the 16 m grid cell size Simrad em3002d multibeam backscatter data only.
Purpose:
The netCDF grids of backscatter imagery were 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 NOAA Ship Hi'ialakai, a 218' United States National Oceanographic and Atmospheric Administration research ship. The NOAA Ship Hi'ialakai's survey sensors include a 30 kHz Simrad EM300 sonar and a 300 kHz Simrad EM3002d sonar, which provide bathymetry and imagery data, a TSS/Applanix POS/MV Model 320, which measures position, velocity, attitude and heading, and a Seabird SBE 9/11 plus CTD used to measure sound velocity profiles.Specific equipment configurations are documented in metadata from cruises: HI0602. 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: 20060217
Ending_Date: 20060224
Currentness_Reference: ground condition
Status:
Progress: Complete
Maintenance_and_Update_Frequency: As needed
Spatial_Domain:
Bounding_Coordinates:
West_Bounding_Coordinate: -170.93
East_Bounding_Coordinate: -170.56
North_Bounding_Coordinate: -14.21
South_Bounding_Coordinate: -14.38
Keywords:
Theme:
Theme_Keyword_Thesaurus: CoRIS Theme Thesaurus
Theme_Keyword:
EARTH SCIENCE > Oceans > Bathymetry/Seafloor Topography > Backscatter
Theme_Keyword: EARTH SCIENCE > Oceans > Coastal Processes > Coral Reefs
Theme:
Theme_Keyword_Thesaurus: None
Theme_Keyword: Acoustic Imagery
Theme_Keyword: Multibeam Backscatter
Theme_Keyword: HI0602
Theme:
Theme_Keyword_Thesaurus: CoRIS Discovery Thesaurus
Theme_Keyword: Geographic Information > Backscatter
Theme:
Theme_Keyword_Thesaurus: ISO 19115 Topic Category
Theme_Keyword: oceans
Theme_Keyword: elevation
Place:
Place_Keyword_Thesaurus: CoRIS Place Thesaurus
Place_Keyword:
OCEAN BASIN > Pacific Ocean > American Samoa > American Samoa (14S170W0000)
Place_Keyword:
COUNTRY/TERRITORY > United States of America > American Samoa > American Samoa > American Samoa (14S170W0000)
Place_Keyword:
OCEAN BASIN > Pacific Ocean > American Samoa > Tutuila Island (14S170W0016)
Place_Keyword:
COUNTRY/TERRITORY > United States of America > American Samoa > American Samoa > Tutuila Island (14S170W0016)
Place:
Place_Keyword_Thesaurus: None
Place_Keyword: South Pacific
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.
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 and the Joint Institute for Marine and Atmospheric Research (JIMAR)
Contact_Person: Jonathan Weiss
Contact_Address:
Address_Type: mailing and physical address
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: jonathan.weiss@noaa.gov
Browse_Graphic:
Browse_Graphic_File_Name:
<ftp://ftp.soest.hawaii.edu/pibhmc/website/data/amsamoa/backscatter/tutuila/tutuila-em3002d-bs-boxes.jpg>
Browse_Graphic_File_Description: Tutuila, 16M Multibeam Backscatter
Browse_Graphic_File_Type: JPEG
Data_Set_Credit: PIBHMC, CRED, PIFSC, NOAA and JIMAR
Native_Data_Set_Environment: netCDF file created using HMRG 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: approximately 1.25 cm Raw sounding resolution: Variable Vertical accuracy of gridded product: 1 percent of water depth
Lineage:
Process_Step:
Process_Description:
Science Applications International Corporation's (SAIC) ISS-2000 acquires, processes and records data, provides survey control and underway quality control displays. SAIC's SABER processing software is used to process the raw soundings, analyze the results, manually edit the sounding data to remove outliers and derive average gridded data values. Additional data acquisition and processing information can be found in the metadata for cruise HI0602. Hawaii Mapping Research Group (HMRG) processing software was then used to extract values of acoustic intensity from the soundings. HMRG is an organization of scientists, engineers and technicians whose mission is to design, build, and operate tools for mapping the seafloor. HMRG is a group within the School of Ocean and Earth Science and Technology at the University of Hawaii at Manoa. The gsf2bs program (July, 2005) converts the swath bathymetry ping records contained within a GSF (Generic Sensor Format) version 2.02 dataset into bs file format. This is done as follows: (i) position each beam's bottom detect intensity sample at the across-track location of that beam's bathymetry value; (ii) assuming a flat bottom in the near neighborhood of the beam, compute across-track distances for all of the beam's remaining intensity samples based on their temporal relation to the bottom detect sample and the computed average sound velocity for that beam as derived from it range and travel time; (iii) after all of the intensity samples from all beams of a ping have been located in across-track distance, fill the gaps between them as necessary by comparing travel times of beams adjacent to the gap, assigning the position using the adjacent sample closest to nadir, and averaging the interpolated values that fall within a cell. The conversion described above is necessary in order to run HMRG backscatter processing operations on the data, such as filtering to remove noise, and to create netCDF grids, raster images and GeoTIFF's. In addition to the standard processing routines applied to Simrad em3002d backscatter data, an additional gain correction was applied to the data to address a systematic mismatch in received acoustic signal strength between the port and starboard sonar heads. Data with a lower strength were multiplied by an empirically determined scaling factor. For more information on the backscatter processing technique see <http://www.soest.hawaii.edu/pibhmc/pibhmc_documentation.htm>. Software_Used: SAIC ISS-2000 Acquisition Software, v 3.4 SAIC SABER Processing Software, v 3.3.15 Hawaii Mapping Research Group (HMRG) Processing Software GMT Generic Mapping Tools, v 4.1 MB System, v 5.0.7
Process_Date: 20070328
Spatial_Data_Organization_Information:
Direct_Spatial_Reference_Method: Raster
Raster_Object_Information:
Raster_Object_Type: Grid Cell
Row_Count: 2407
Column_Count: 2830
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: 0
Planar_Coordinate_Information:
Planar_Coordinate_Encoding_Method: Row and Column
Coordinate_Representation:
Abscissa_Resolution: 16
Ordinate_Resolution: 16
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:
Sidescan data within a GSF 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: PIBHMC, CRED, PIFSC, NOAA and JIMAR
Contact_Person: Jonathan Weiss
Contact_Position: Seafloor Mapping Specialist
Contact_Address:
Address_Type: mailing and physical address
Address: 1680 East-West Road, POST 833
City: Honolulu
State_or_Province: Hawaii
Postal_Code: 96822
Country: USA
Contact_Voice_Telephone: 808-956-5239
Contact_Electronic_Mail_Address: jonathan.weiss@noaa.gov
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: netCDF, .grd
Format_Information_Content:
This file is formatted as a 2-D binary netCDF grid file. This is the default grid file format used by GMT (Generic Mapping Tools). The file was created by the HMRG sofware program bsovl. More information about netCDF files can be found at at <http://www.soest.hawaii.edu/gmt/> and <http://www.unidata.ucar.edu/software/netcdf/>.
File_Decompression_Technique: Unzip
Digital_Transfer_Option:
Online_Option:
Computer_Contact_Information:
Network_Address:
Network_Resource_Name: <http://www.soest.hawaii.edu/pibhmc>
Fees: None
Standard_Order_Process:
Digital_Form:
Digital_Transfer_Information:
Format_Name: GeoTIFF, .tif
Format_Information_Content:
TIFF is a format for storage, transfer, display, and printing of raster images. The TIFF file structure allows both the tag and the image data to be encoded into the same file. GeoTIFF refers to a TIFF file that has geographic data embedded as tags within the TIFF file. The geographic data can be used to position the image in the correct location and geometry on the screen of a geographic information display. Any GIS, CAD, Image Processing, Desktop Mapping and other types of systems using geographic images can read any GeoTiff file. More specifically, files of this type can be added to ArcInfo and ArcView 8.x or higher and may be viewed in the Table of Contents as a new raster layer. Image visualization software that does not use geography as a basis for image placement can view a GeoTIFF image as if there were no geographic information in the TIFF file. For example, GeoTIFF files can be viewed using Windows Picture and Fax viewer.The GeoTIFF format is public domain, non-proprietary.
File_Decompression_Technique: Unzip
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: 20080812
Metadata_Contact:
Contact_Information:
Contact_Organization_Primary:
Contact_Organization: PIBHMC, CRED, PIFSC, NOAA and JIMAR
Contact_Person: Jonathan Weiss
Contact_Position: Seafloor Mapping Specialist
Contact_Address:
Address_Type: mailing and physical address
Address: 1680 East-West Road, POST 833
City: Honolulu
State_or_Province: Hawaii
Postal_Code: 96822
Country: USA
Contact_Voice_Telephone: 808-956-5239
Contact_Electronic_Mail_Address: jonathan.weiss@noaa.gov
Metadata_Standard_Name: FGDC Content Standard for Digital Geospatial Metadata
Metadata_Standard_Version: FGDC-STD-001-1998
Generated by mp version 2.8.23 on Fri Sep 5 04:18:55 2008