NCCOS Mapping: Geospatial products of water depth, acoustic backscatter, and ROV data collected from NOAA Ship Nancy Foster in the Tortugas South Ecological Reserve and Florida Keys National Marine Sanctuary from 2020-09-07 to 2020-09-16 (NCEI Accession 0295610)

The Nancy Foster is outfitted with Kongsberg EM2040 and EM710 multibeam echo sounder systems (MBES), as well as a Simrad EK60 split beam echosounder system (SBES) for water column and fisheries acoustics. MBES data for NF-20-08 was collected using only the EM710. The Nancy Foster's EM2040 was out of order during this mission from a major system failure that occurred on August 31st, prior to the FKNMS EFH cruise. Raw EK60 data was collected, but are not included in this data package. All acquisition and processing workstations are located in the Dry Lab of the Nancy Foster, are networked as a workgroup, and are interfaced with the ship’s backup system. Coastal Oceanographics Hypack 2018 was used for vessel navigation and survey line planning. Kongsberg Seafloor Information System (SIS) software was used to acquire the EM710 bathymetric data in the .all and .wcd formats. The reference point for all vessel offsets and lever arms was set as the IMU at 0,0,0 in all acquisition systems. Transducer, Surface Sound Speed, and GPS antenna offsets were input into the SIS acquisition system. The CARIS vessel configuration file for processing this survey only contains the patch test values and uncertainty values, so that any offsets were not double applied. Nancy Foster used an Applanix POS/MV 320 Version 5 GNSS inertial system with Trimble BD982 receivers to measure attitude, heading, heave, and position for the MBES system. The POS/MV consists of an Inertial Motion Unit (IMU), two dual frequency GNSS antennas and a topside control unit. The POS/MV is augmented in real time with Fugro Marinestar Satellite service which improves the POS/ MV positional accuracies to sub-DGPS standards. The POS/MV position, timing, heading and motion data were output to the Hypack and SIS acquisition systems using the POS/MV real-time ethernet option at 25 Hz. Additionally, using the ethernet logging controls, the POS/MV was configured to log TrueHeave™ and all of the raw observable groups needed to post process real-time navigation data. The POS/MV logged 13 megabyte files, which resulted in multiple files created per day Acoustic backscatter was collected with both Kongsberg systems for benthic habitat delineation and chart creation. The Marine Spatial Ecology Division processed backscatter in Fledermaus Geocoder Toolbox (FMGT).