Cruise 64PE431: a south to north hydrographic transect in the central Caribbean Sea in February 2018.
|Temporal extent||2018-02-04 -2018-02-11|
|Author(s)||de Jong Marieke Femke1|
|Affiliation(s)||1 : NIOZ Royal Netherlands Institute for Sea Research and Utrecht University, Department of Ocean Systems (OCS), P.O. Box 59, 1790 AB Den Burg, Texel, the Netherlands|
|Note||Data included in this DOI is CTD data. Other data mentioned in the cruise report is available on request.|
|Keyword(s)||CTD, Caribbean Sea, hydrography, Pelagia, 64PE431, NICO, anticyclone|
This data set consist of CTD data collected on board the RV Pelagia during cruise 64PE431. This cruise started in Oranjestad, Aruba on 4 February 2018 and ended in Phillipsburg, Sint Maarten on 11 February 2018. The cruise consisted of a survey across the Caribbean Sea, with hydrographic stations performed between the 1200 m isobath north of Aruba to the 800 m isobaths just south of the Dominican Republic. The aim of these measurements was to document the background hydrography of the Caribbean Sea as well as the hydrographic and velocity structure of a Caribbean anticyclone. A large anticyclone was detected north of Aruba with the use of altimetry field before the start of the cruise. The CTD station positions were adjusted in order to transect the center of this anticyclone. Furthermore four Argo floats provided by the European Argo program were deployed at hydrographic stations. Details on the floatnumbers can be found in the cruise report.
|Acknowledgements||This work is part of the Netherlands Initiative Changing Oceans (NICO) research programme, which is (partly) financed by the Netherlands Organisation for Scientific Research (NWO).|
A recently (November 2017) calibrated SBE 9/11+ CTD has been used to measure temperature, salinity, and chlorophyll/turbidity profiles. The sensors mounted on the CTD were an SBE3 temperature sensor SN-032118, SBE4 conductivity sensor SN-1204, a Digiquatz pressure sensor SN-127486. Also mounted were a Wetlabs CStar beam transmission meter SN-CST-1406DR (calibrated September 2017) with a path length of 25 cm and a SBE43 Oxygen sensor SN-043-0350 (calibrated July 2016). Chlorophyll was recorded by a Chelsea Aqua 3 Fluorometer SN-092 (calibrated October 2017) and a Wetlabs ECO-FLNT NS-4787 (calibrated July 2017) that additionally measured turbidity. PAR/Irradiance was measured by a Chelsea licor sensor SN-118 (calibrated July 2014). The CTD was mounted in a rack containing water samplers.
Four salinity samples were taken from the up-cast of each of the CTD stations. Depths with minimum salinity gradients were selected for these samples. The sample bottles were taken to the labcontainer in the ship’s hold where they rested for at least 24 hour to equilibrate to container temperature. The samples were analysed on the Guildline Autosal SN-66179. Each measurement started and ended with a standard seawater calibration, OSIL batch P161. Additional standard calibration was done every 15 samples. Results from these reference salinity measurements were used to calibrate the CTD conductivity sensor.
For the data collection the Seasave software for Windows (version V 7.26.7), produced by SBE, was used. The CTD data were recorded with a frequency of 24 data cycles per second. After each CTD cast the data were copied to the appropriate directory on the hard disk of the ship's computer network, where a daily back-up copy was made.