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author Kopte, Robert
Schulz-Bull, Detlef E
Waniek, Joanna J
Frazão, Helena C
author_facet Kopte, Robert
Schulz-Bull, Detlef E
Waniek, Joanna J
Frazão, Helena C
collection Datos científicos de ciencias marinas y ambientales
contents Current velocities of the upper water column along the cruise track of R/V Sonne cruise SO296/1 were collected by a vessel-mounted 75 kHz RDI Ocean Surveyor ADCP. The ADCP transducer was located at 6.0 m below the water line. The instrument was operated in narrowband mode (WM10) with a bin size of 8.00 m, a blanking distance of 8.00 m, and a total of 100 bins, covering the depth range between 22.0 m and 814.0 m. Heading, pitch and roll data from the ship's motion reference unit and the navigation data from the Global Positioning systems were used by the data acquisition software VmDAS internally to convert ADCP velocities into earth coordinates. Single-ping data were screened for bottom signals and, where appropriate, a bottom mask was manually processed. The ship's velocity was calculated from position fixes obtained by the Global Positioning System (GPS). Accuracy of the ADCP velocities mainly depends on the quality of the position fixes and the ship's heading data. Further errors stem from a misalignment of the transducer with the ship's centerline. Data post-processing included water track calibration of the misalignment angle (-0.1252° +/- 0.4024°) and scale factor (1.0042 +/- 0.0075) of the Ocean Surveyor signal. The velocity data were averaged in time using an average interval of 60 s. Velocity quality flagging is based on different threshold criteria: Depth cells with ensemble-averaged percent-good values below 25% are marked as 'bad data'. Depth cells with velocities above 1.5 m/s are flagged as 'bad data'. Depth cells with a root-mean-square deviation between the measured ensemble-average velocity and a cell-wise running-mean velocity above 0.3 m/s are flagged as 'probably bad data'.
format Dataset Open Access
id pangaea_https___doi_org_10_1594_PANGAEA_966067
institution PANGAEA
language en
publishDate 2024
publisher PANGAEA
record_format pangaea
spellingShingle Shipboard ADCP current measurements (75 kHz) during RV SONNE cruise SO296/1
Kopte, Robert
Schulz-Bull, Detlef E
Waniek, Joanna J
Frazão, Helena C
Current velocity, east-west; Current velocity, north-south; DAM_Underway; DAM Underway Research Data; DataHub; DataHub Earth and Environment of the Helmholtz Association; DATE/TIME; DEPTH, water; Echo intensity, relative; LATITUDE; LONGITUDE; MAPUCHE; Pings, averaged to a double ensemble value; Quality flag, current velocity; Seadatanet flag: Data quality control procedures according to SeaDataNet (2010); SO296/1; SO296/1_0_Underway-4; Sonne_2; Vessel mounted Acoustic Doppler Current Profiler [75 kHz]; VMADCP-75
Current velocities of the upper water column along the cruise track of R/V Sonne cruise SO296/1 were collected by a vessel-mounted 75 kHz RDI Ocean Surveyor ADCP. The ADCP transducer was located at 6.0 m below the water line. The instrument was operated in narrowband mode (WM10) with a bin size of 8.00 m, a blanking distance of 8.00 m, and a total of 100 bins, covering the depth range between 22.0 m and 814.0 m. Heading, pitch and roll data from the ship's motion reference unit and the navigation data from the Global Positioning systems were used by the data acquisition software VmDAS internally to convert ADCP velocities into earth coordinates. Single-ping data were screened for bottom signals and, where appropriate, a bottom mask was manually processed. The ship's velocity was calculated from position fixes obtained by the Global Positioning System (GPS). Accuracy of the ADCP velocities mainly depends on the quality of the position fixes and the ship's heading data. Further errors stem from a misalignment of the transducer with the ship's centerline. Data post-processing included water track calibration of the misalignment angle (-0.1252° +/- 0.4024°) and scale factor (1.0042 +/- 0.0075) of the Ocean Surveyor signal. The velocity data were averaged in time using an average interval of 60 s. Velocity quality flagging is based on different threshold criteria: Depth cells with ensemble-averaged percent-good values below 25% are marked as 'bad data'. Depth cells with velocities above 1.5 m/s are flagged as 'bad data'. Depth cells with a root-mean-square deviation between the measured ensemble-average velocity and a cell-wise running-mean velocity above 0.3 m/s are flagged as 'probably bad data'.
title Shipboard ADCP current measurements (75 kHz) during RV SONNE cruise SO296/1
topic Current velocity, east-west; Current velocity, north-south; DAM_Underway; DAM Underway Research Data; DataHub; DataHub Earth and Environment of the Helmholtz Association; DATE/TIME; DEPTH, water; Echo intensity, relative; LATITUDE; LONGITUDE; MAPUCHE; Pings, averaged to a double ensemble value; Quality flag, current velocity; Seadatanet flag: Data quality control procedures according to SeaDataNet (2010); SO296/1; SO296/1_0_Underway-4; Sonne_2; Vessel mounted Acoustic Doppler Current Profiler [75 kHz]; VMADCP-75
url https://doi.org/10.1594/PANGAEA.966067