Gridded (5 m cell size) bathymetry of the shelf and slope environments of Tutuila Island, American Samoa, South Pacific. Almost complete bottom coverage was achieved in depths between 2 and 3409 meters (5 m grid includes data to 250 m). The bathymetry dataset includes Simrad EM300, EM3002D, and Reson 8101ER multibeam data collected during Jan. to March of 2004 and during Feb. to March of 2006.
The data were collected in support of Coral Reef Conservation Program goals to map all shallow (0-30 m) coral reefs in US Pacific waters and priority moderate (> 30 m) depth areas by 2009. The data are being used to provide bathymetric and backscatter data for previously unmapped areas; in support of ecosystem management requirements for benthic habitat mapping and location of Essential Fish Habitat; and to study the geologic features of the area.
Data were collected aboard the NOAA Ship Hiialakai, a 218' United States National Oceanographic and Atmospheric Administration research ship. The NOAA Ship Hiialakai'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. Sensor configuration for the Hi'ialakai for cruise HI-06-02 is documented in the cruise/multibeam metadata file HI0602_MB_Metadata.txt. Data were also 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 R/V AHI's survey sensors include a 240 kHz RESON 8101-ER sonar providing bathymetry and imagery data, a TSS/Applanix POS/MV Model 320 which measures position, velocity, attitude and heading, and a Seabird SBE 19 CTD used to measure sound velocity profiles. Sensor configuration for the AHI for cruise AHI-06-02 is documented in the cruise/multibeam metadata file AHI0602_MB_Metadata.txt. Sensor configuration for the AHI for cruise AHI-04-02 is documented in the cruise/multibeam metadata file AHI0402_MB_Metadata.txt. Additional data for the Faga'itua bay area were gathered by the Kongsberg Simrad EM-3000 system, contracted from the Center for Coastal Ocean Mapping of the University of South Florida (USF), and operated from a boat owned by the Department of Marine & Wildlife Resources (DMWR) of the America Samoa Government. For more information please contact: Dawn Wright email:dawn@dusk.geo.orst.edu
ground condition
These data are not to be used for navigation purposes. Please acknowledge the NOAA Coral Reef Ecosystem Division, Pacific Islands Fisheries Science Center and the Pacific Islands Benthic Habitat Mapping Center, School of Ocean and Earth Science and Technology, University of Hawaii as the sources of this information.
NOAA IRC
NMFS/PIFSC/CRED
1845 WASP Blvd., Building 176
e-mail preferred
http://www.soest.hawaii.edu/pibhmc/amsamoa_images/Tutuila_5m_445px.jpg
Coral Reef Ecosystem Division (CRED), Pacific Islands Fisheries Science Center (PIFSC), NOAA and Pacific Islands Benthic Habitat Mapping Center, School of Ocean and Earth Science and Technology, University of Hawaii
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.
These data are believed to be logically consistent though no tests were performed
Complete
Horizontal positioning system: GPS C/A Horizontal position accuracy: 25 meters
Range resolution of sonar: varies with depth Raw sounding resolution: varies with depth Vertical accuracy of gridded product ~ 1% of water depth
Specifics of data processing are recorded in cruise metadata reports HI0602_MB_Metadata.txt, AHI0602_MB_Metadata.txt, AHI0402_MB_Metadata.txt
Depth values are real values based on the average of the soundings that fell within the extracted grid cells. The number of soundings per grid cell range from >1000 soundings in shallow depths to as few as 20 soundings in deeper areas. A total error budget for this survey has not been developed. Therefore, the accuracy of depth measurements should be considered to be within 1 per cent of water depth.
none
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.
Binary netCDF Grid: 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), which created this file. More information can be located at http://gmt.soest.hawaii.edu and http://unidata.ucar.edu/packages/netcdf/index.html and in http://www.ldeo.columbia.edu/res/pi/MB-System/formatdoc/gsf_spec.pdf
Arc ASCII can be converted to Arc Raster using ArcToolbox Conversion Tools.
