The EUREC4A-OA oceanographic campaign that took place in January-February 2020 in the tropical North-West Atlantic Ocean aboard several research vessels, was a contribution to the broader international research initiative EUREC4A (http://eurec4a.eu/). The cruise was carried out in conjunction with the research vessels L'Atalante (France), Maria S. Merian and Meteor (Germany) and the Ron Brown (USA) as well as with the aircraft and UAV operations and continuous observations from the ground site on the island of Barbados (BCO) and the Saildrone© operations as part of the US ATOMIC project. This dataset is composed of the uCTD measurements obtained from the R/Vs L'Atalante and Maria S. Merian, processed using a toolbox from GEOMAR-PO based on the article from Ullman and Hebert (JAOT, 2014). A secondary quality check is performed by comparing the uCTD measurements with the nearest CTD stations. Important Note: This submission has been initially submitted to SEA scieNtific Open data Edition (SEANOE) publication service and received the recorded DOI. The metadata elements have been further processed (refined) in EMODnet Ingestion Service in order to conform with the Data Submission Service specifications.

As part of the EUREC4A-OA project, which is the French oceanographic component of the larger EUREC4A field experiments, the fugacity of CO2 (fCO2) was measured underway during the EUREC4A campaign in the region 50°W-62°W – 5°N-16°N.   Important Note: This submission has been initially submitted to SEA scieNtific Open data Edition (SEANOE) publication service and received the recorded DOI. The metadata elements have been further processed (refined) in EMODnet Ingestion Service in order to conform with the Data Submission Service specifications.

The EUREC4A-OA oceanographic campaign that took place in January-February 2020 in the tropical North-West Atlantic Ocean aboard the research vessel L'Atalante was a contribution to the broader international research initiative EUREC4A (http://eurec4a.eu/). The cruise was carried out in conjunction with the research vessels Maria S. Merian and Meteor (Germany) and the Ron Brown (USA) as well as with the aircraft and UAV operations and continuous observations from the ground site on the island of Barbados (BCO) and the Saildrone© operations as part of the US ATOMIC project. The overall objective of the EUREC4A-OA campaign was to collect observational data that will enable research on dynamic and thermodynamic processes in the atmosphere and the ocean, in order to better understand the role of fine ocean scales both in the internal dynamics of the ocean and in air-sea interactions.  To this end, measurements of oceanic and atmospheric profiles have been carried out to observe the temporal evolution and spatial heterogeneity of the atmospheric and oceanic boundary layers and the properties in these two fluids beyond these layers. Autonomous observation platforms (submarine glider, Argo profiling floats, surface buoys and the OCARINA and PICCOLO prototypes) complemented the observations carried out on board ships. Important Note: This submission has been initially submitted to SEA scieNtific Open data Edition (SEANOE) publication service and received the recorded DOI. The metadata elements have been further processed (refined) in EMODnet Ingestion Service in order to conform with the Data Submission Service specifications.