This record describes multibeam echosounder data collected on the RV Investigator voyage IN2016_V03, 'Monitoring Ocean Change and Variability along 170° W from the ice edge to the equator', which departed Hobart on the 26 April 2016 and returned to Lautoka, Fiji on the 30 June 2016. There was a port call at Wellington, New Zealand, 26 - 27 May for some science personnel change; this resulted in two "legs" of the voyage therefore Leg 1 is 26 April - 26 May 2016, and Leg 2 27 May - 30 June 2016.
The Kongsberg EM122 multibeam echosounder was used to acquire seafloor bathymetry and backscatter information on both legs and watercolumn backscatter information on Leg 2.
The EM122 provides a 1 degree by 1 degree angular resolution. The echosounder's nominal frequency is 12 kHz.
Data are stored in .all raw format for bathymetry and backscatter and .wcd format for watercolumn backscatter at CSIRO. There are 2516 files totalling 75.6 GB of raw data in this dataset.
Sound velocity profiles were applied to this data during data acquisition. Bathymetry data contained in *.all format is corrected for motion and position.
Tide corrections were not applied to the processed data. Processed data had outliers removed. Processed line data are available in *.gsf and ascii format, and processed bathymetry grids in geotiff format.
Additional information regarding this dataset, including information on processing streams, is contained in the GSM data acquisition and processing report. Additional data products may be available on request.
