RV Investigator Voyage IN2025_V03 EM2040 MKII Multibeam Echosounder Data

This record describes multibeam echosounder data collected on RV Investigator voyage IN2025_V03, titled "COAST‐k – Clean Ocean Air Sampling upwind of Tasmania ‐ kennaook" which departed Hobart on the April 29, 2025 and returned to Hobart on the May 18, 2025.The EM2040MK2 provides a 0.4 degree by 0.7 degree angular resolution. The echosounder's nominal frequency is 400 kHz (with a range of 200-700 kHz) and it operated in dual swath mode. Data are stored in *.kmall raw format for bathymetry and backscatter and *.kmwcd format for watercolumn backscatter at CSIRO. There are 158 files totalling 71.3 GB of raw data and 146 files totalling 424 GB of watercolumn data in this dataset. Sound velocity profiles were applied to this data during data acquisition. Bathymetry data contained in *.kmall format are corrected for motion and position. GPS tide was computed using the EGM2008 model and applied to the processed data. Processed data has had outliers removed. Additional information regarding this dataset, including further information on processing streams, is contained in the GSM data acquisition and processing report.