Processed 2 minutes-averaged continuous VM-ADCP (vessel-mounted Acoustic Doppler Current Profiler) profiles during POLARSTERN cruise PS95

DOI

This data set was collected during the R. V. Polarstern cruise PS95. Outside territorial waters, current velocities were measured nearly continuously along the ship's track with a vessel-mounted TRD Instruments 153.6-kHz Ocean Surveyor ADCP. The transducers were located 11 meters below the water line and were protected against ice floes by an acoustically transparent plastic window. The current measurements used a pulse of 2 seconds and vertical bin length of 4 meters. The ship's velocity was calculated from position fixes obtained by the Global Positioning System (GPS). Heading, roll and pitch data from the ship's gyro platforms and the navigation data were used to convert the ADCP velocities into earth coordinates. The 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. The ADCP data were processed using the Ocean Surveyor Sputum Interpreter (OSSI) software developed by GEOMAR Helmholtz-Zentrum für Ozeanforschung Kiel. The reference layer was set to avoid near surface effects. The averaging interval was set to 120 seconds.Sampling interval setting: 2s; Number of bins: 80; Bin length: 4m; Pulse length: 4m; Blank beyond transmit length: 4m.Data processing setting: Upper depth of reference layer: 30m; Lower depth of reference layer: 80m; Time average: 120s; Misalignment angle: 0.845; amplitude: 1.0170.The precision for single ping and 4m cell size reported by TRDI is 0.30m/s. Resulting from the single ping precision and the number of pings (most of the time 36) during 120seconds the velocity accuracy is nearly 0.05m/s.(Velocity accuracy = single ping precision divided by square root of the number of pings).

Identifier
DOI https://doi.org/10.1594/PANGAEA.892103
Related Identifier References https://doi.org/10.2312/BzPM_0702_2016
Related Identifier References https://doi.org/10.1594/PANGAEA.859919
Metadata Access https://ws.pangaea.de/oai/provider?verb=GetRecord&metadataPrefix=datacite4&identifier=oai:pangaea.de:doi:10.1594/PANGAEA.892103
Provenance
Creator Witte, Hannelore
Publisher PANGAEA
Contributor Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research, Bremerhaven
Publication Year 2018
Rights Creative Commons Attribution 3.0 Unported; https://creativecommons.org/licenses/by/3.0/
OpenAccess true
Representation
Resource Type Dataset
Format text/tab-separated-values
Size 3258345 data points
Discipline Acoustics; Engineering Sciences; Mechanical and industrial Engineering; Mechanics and Constructive Mechanical Engineering
Spatial Coverage (-25.126W, -33.837S, 18.275E, 48.176N)
Temporal Coverage Begin 2015-11-01T20:44:00Z
Temporal Coverage End 2015-12-01T05:16:00Z