Predicted tides were applied to the data in real time. At Jarvis Island, Hilo (1617760) predicted tides were used with a +2.0 time corrector and a range ratio of 1.10. At Palmyra and Kingman, Honolulu (1612340) predicted tides were used with a +1 hr 19 min time corrector and a range ratio of 0.56.
Horizontal accuracy is 20m (no differential GPS correctors applied), vertical accuracy is depth dependent (~1% of water depth), WGS84 datum. These data are not to be used for navigation. Depths mapped range from 20 to 3500 m. Concurrent mapping was done by the R/V AHI in water depths ranging from 10-250 m with the data set being AHI-06-04; metadata for AHI-06-04 are submitted separately.
The Hi'ialakai's equipment serial numbers, software versions and sensor configuration settings are as follows:
SIMRAD EM300 multibeam echosounder Serial #: 303 PU Software Versions: 1.1.3 040427,2.0.0 040614,2.3.2 040615,2.0.1 040629 SIS Software Version: 1.0, build 117, July 2, 2004
HI'IALAKAI POS/MV Model 320, version 3 PCS serial #: 295 IMU serial #: 1333 PCS Firmware: 2.21, Feb 02, 2006 Controller software: v 2.1
Seabird SBE 9/11 plus CTD: Serial #: 09P35130-0737
Hi'ialakai Lever Arm Distances and Alignment Offsets: The Hi'ialakai's Reference Point (RP) is a granite block situated 1.222 m starboard of the ship's centerline, 1.23 m above the ship's baseline/datum on the keel. The RP is located under the forward deck, in the ship's laundry room. The ship's sensors, the sonar systems and permanent benchmarks are measured with respect to the RP. Positive X means the point is forward of the RP, positive Y means the point is to starboard of the RP, positive Z means the point is below the RP. The survey waterline is defined to be at the 15' draft mark on the vessel's starboard side.
POS/MV Settings: X Y Z RP to IMU, m 0.434 0.000 -0.117 RP to Primary GPS(port),m -18.101 -2.011 -23.545 RP to Vessel, m 0.00 0.00 0.00 IMU w.r.t. Ref. Frame, deg 0.00 0.00 0.00 RP to Heave lever arm, m -14.532 -1.179 -5.234 Sensor 1 & 2 lever arms & angles: 0 0 0 Antenna Baseline Distance: 1.779
EM300 Settings: X Y Z Pos sensors 1 2 & 3, m 0 0 0 TX Transducer, m -04.091 -2.217 1.727 RX Transducer, m -06.065 -1.222 1.727 Attitude sensors 1 & 2, m 0 0 0 Waterline, m -3.26 Roll Pitch Heading TX Transducer, deg 0.00 0.00 359.96 RX Transducer, deg 0.00 0.00 0.05 Attitude 1, deg -0.20 0.00 0.00 Attitude 2, deg 0 0 0 Stand-alone heading, deg 0
Resource Description: EM300 Multibeam Sonar Data from Cruise Hi'ialakai HI-06-04
These data are also archived through NOAA's National Geophysical Data Center at <http://www.ngdc.noaa.gov/mgg/bathymetry/multibeam.html>
Data Format - Generic Sensor Format, as described in <http://www.ldeo.columbia.edu/res/pi/MB-System/formatdoc/gsf_spec.pdf>