RQM - CTD Data From the Coriolis Concerted Mission (MAC2020): Odyssée Saint-Laurent 2020

The September 2020 concerted mission, funded by the Odyssée Saint-Laurent program of the Réseau Québec maritime (RQM), aimed to gather strategic scientific knowledge destined for the understanding and management of the St. Lawrence River and Gulf. This mission enabled extensive data acquisition for 9 research projects, largely focused on sediment sampling and analysis, as well as the study of drift currents as part of the TReX (TRacer Release eXperiment, RQM-MEOPAR) project. Particular attention was paid to characterize the industrial port areas of Sept-Îles, Baie-Comeau and Port-Cartier.

Vertical profiles of CTD data (conductivity, temperature, depth) were made in the water column at 36 stations between the mouth of the Saguenay River and the Îles-de-la-Madeleine in the Gulf of St. Lawrence. These profiles were taken from the surface to a maximum of 5 m from the seabed. They include measurements of temperature, salinity, density, dissolved oxygen, light transmission, vertical stratification, and sound velocity in seawater. Discrete water samples were collected at various stations and depths to compare CTD's direct measurements with laboratory analyses of dissolved oxygen concentration (11 samples, 5 stations, Winkler chemical titration). These comparisons were used to adjust the calibration of dissolved oxygen data from the CTD.