Gridded bathymetry (1m) of Reef Runway ship grounding site, Oahu, Hawaii, USA. The data include multibeam bathymetry from the Reson 8101 multibeam sonar collected in April, 2015 by the NOAA Coral Reef Ecosystem Division in depths between ~ 3.5 and 12.5 meters.
The ASCII grid was created using data gathered from multibeam soundings to document the impact of a ship grounding on the benthic habitat, and for use as a planning and reference document. Further data were collected to fill gaps in the existing bathymetry. Refer to supplemental information for description of instrument and survey.
Data were collected aboard the R/V AHI (Acoustic Habitat Investigator), a 8 m (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 which measures bathymetry and acoustic backscatter imagery, a TSS/Applanix POS/MV Model 320 which measures time, position, velocity, attitude and heading, and a Seabird SBE 19 Plus CTD used to measure sound velocity profiles. Specific equipment configurations are documented in metadata from cruise AHI1502. These metadata can be accessed at: <http://www.soest.hawaii.edu/pibhmc/cms/cruise-catalog/>
ground condition
These data are not to be used for navigation purposes. Please acknowledge NOAA Pacific Islands Fisheries Science Center, and the Joint Institute for Marine and Atmospheric Research (JIMAR) 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/MHI_images/ReefRunway_grounding_site_2015_445.jpg
PIBHMC, CRED, PIFSC, NOAA and JIMAR
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 (SPS) Horizontal position accuracy: 25 m
1 m Raw sounding resolution: Variable
Multibeam swath files are acquired in the Generic Sensor Format (GSF) and are edited on a swath by swath basis using SAIC's SABER editing software. The edited swath files are then combined into a Pure File Magic (PFM) format with a defined grid cell size (1 m) in SABER and area based editing is performed. The edited PFM is then exported as X,Y,Z data with a value at each grid node. The X,Y,Z data are then gridded using nearneighbor, a Generic Mapping Tools (GMT) algorithm that converts an ASCII or binary table to a netCDF grid file format. NetCDF grids are then converted to an ArcGIS ASCII file format using LINUX/UNIX commands in combination with GMT. GMT is an open source collection of tools for manipulating geographic data sets. Additional information about GMT can be found at: <http://www.soest.hawaii.edu/gmt> and additional information about the multibeam data processing is recorded in the cruise metadata.
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 meter.
none
1845 Wasp Blvd., Bldg. 176
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.
These data can be downloaded as either a 2-D binary netCDF raster grid or an ArcGIS ASCII text file. The netCDF grid is the default grid file format used by GMT (Generic Mapping Tools), which created this file. More information can be located at <http://www.soest.hawaii.edu/gmt/> and <http://www.unidata.ucar.edu/software/netcdf/>. The Arc ASCII file, for use in ESRI's (<http://www.esri.com>) GIS software, can be converted to an Arc Raster Grid using ArcToolbox ASCII to Raster conversion tool.
