MARLEY (Monitoring deep-seA coRaL EcosYstems) is a deep seafloor observing system dedicated to the monitoring of cold-water coral habitats. The system is deployed in the Lampaul canyon off Brittany, France since August 2021 and maintained each year during the ChEReef-Obs cruises. The study site is a coral garden dominated by Madrepora oculata, located on a sedimented platform at 780 m depth. MARLEY is equipped with a CTD SBE 37-SIP, an oxygen optode Aanderaa (4330 or 4831), an ADCP Teledyne RDI Workhorse 300kHz, a turbidity sensor Wetlabs ECO NTU (sensitivity: 0-1000 NTU), a sediment trap Technicap PPS 4/3 – 24 bottles and a camera module. The camera module, which can be moved from up to 30 m from the main station, is equipped with a camera AXIS Q1786, two flash lights and a fluorometer & scattering meter SEA-BIRD ECO FLNTU. All sensors are controlled and synchronised by the Communication and Storage Front-end - 2nd generation (COSTOF2), which is also managing data storage. Optical sensors are protected from fouling by electrochlorination (20 seconds, each 6 hours). The oxygen optode is calibrated each year prior to deployment. These datasets provide raw data from the oxygen optode Aandera 4831, the CTD Seabird SBE37, the Wetlabs ECO NTU and the SEAR-BIRD ECO FLNTU covering the period 28/08/2021 to 19/01/2022, with a frequency of 15 minutes. Data from Wetlabs ECO NTU include raw counts and Nephelometric Turbidity Unit (NTU) derived from manufacturer’s calibration with Scale Factor = 0.0611 and Dark Counts = 50. Data form SEABIRD ECO FLNTU include raw counts at 695 nm (Chlorophyll) and 700 nm (Turbidity). Chlorophyll concentration (µg/l) is derived from manufacturer’s calibration with Scale Factor = 0.0180 and Dark Counts = 48. Nephelometric Turbidity Unit (NTU) is derived from manufacturer’s calibration with Scale Factor = 0.0481 and Dark Counts = 50. 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.

This dataset consists of a glider deployment in greater Te Moana-o-Raukawa (Cook Strait) as part of the DeepSouth National Science Challenge in Aotearoa New Zealand. This submission continues from previous deployments uploaded to SEANOE (doi:10.17882/76530). Survey uses a Teledyne Webb Research Slocum G2 glider equipped with a pumped SeaBird CTD to measure conductivity, temperature, and pressure, along with instruments to measure dissolved oxygen, chlorophyll-a fluorescence, backscatter at 470, 532, 660, and 700nm, chromophoric dissolved organic matter (CDOM), and photosynthetically active radiation (PAR). Part-way through the deployment, in order to save battery, the science package was turned on only during downcasts and these subsequently appear as empty casts in the dataset. Science data were processed using the GEOMAR Glider Toolbox (https://git.geomar.de/open-source/geomar_glider_toolbox). Comparison with the previously-utilized SOCIB (Troupin et al. (2015), doi: 10.1016/j.mio.2016.01.001) toolbox shows negligible differences in outputs. Data have been averaged into vertical bins of 1dBar (~1m). Despite processing to minimize lag-error in salinity (following Garau et al., 2011, doi: 10.1175/JTECH-D-10-0503.1), some casts (n=10, out of 4246 total) were made empty after visual inspection in T-S space. Oxygen data were lag-corrected, whereas other variables are presented as-is without further processing. Depth-integrated water velocity derived from GPS and dead-reckoning are included. 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.

This dataset contains turbidity (NTU) data acquired between August 2018 and June 2019 using a Wetlabs turbidimeter (ECO-BBRTD, serial # 215R) installed horizontally at 1.5 m height at the top of the SeaMoN East frame. The sensor was not calibrated as the sizes of the natural particles are unknown. Data was acquired every 15 minutes. The instrument is part of the SeaMoN East ecological monitoring node deployed at ca 10m away from the active hydrothermal edifice Tour Eiffel. Deployment : 2018/08/23 -Victor 6000 Dive 707-12 (Momarsat 2018 cruise https://doi.org/10.17600/18000514) Recovery : 2019/06/15 - Nautile dive 1942-04 (Momarsat 2019 cruise (https://doi.org/10.17600/18001110)-[https://doi.org/10.17600/18000514]) Location : 37.8N, 36.77S, -31.64E, -32.91W   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.

This dataset contains turbidity (NTU) data acquired between April 2015 and September 2016 using a Wetlabs turbidimeter (ECO-BBRTD, serial # 215R) installed horizontally at 1.5 m height at the top of the SeaMoN East frame. The sensor was not calibrated as the sizes of the natural particles are unknown. Data was acquired every 15 minutes. The instrument is part of the SeaMoN East ecological monitoring node. 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 French Atlantic coast hosts numerous macrotidal and turbid estuaries that flow into the Bay of Biscay that are natural corridors for migratory fishes. The two best known are those of the Gironde and the Loire. However, there are also a dozen estuaries set geographically among them, of a smaller scale. The physico-chemical quality of estuarine waters is a necessary support element for biological life and determines the distribution of species, on which many ecosystem services (e.g. professional or recreational fishing) depend. With rising temperatures and water levels, declining precipitation and population growth projected for the New Aquitaine region by 2030, the question of how the quality and ecological status of estuarine waters will evolve becomes increasingly critical. The MAGEST (Mesures Automatisées pour l’observation et la Gestion des ESTuaires nord aquitains) high-frequency monitoring of key physico-chemical parameters was first developed in the Gironde estuary in 2004 ; the Seudre and Charente estuaries were instrumented late 2020. First based on real-time automated systems, MAGEST is now equipped by autonomous multiparameter sensors. Depending of the stations, an optode is also deployed to secure dissolved oxygen measurement. By the end of 2020, MAGEST had 12 instrumented sites. Portets is a measuring station located in the upper Gironde estuary (Garonne subestuary, about 20 km upstream of the Bordeaux metropolis. 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.

86 CTD casts collected by Marine Scotland Science on cruise FRV Scotia 1119S in the North Sea.

19 CTD casts collected by Marine Scotland Science on cruise FRV Scotia 1319S in the North East Atlantic Ocean.

68 CTD casts collected by Marine Scotland Science on cruise FRV Scotia 1819S in the North Sea and North East Atlantic Ocean.

39 CTD casts collected by Marine Scotland Science on cruise FRV Scotia 0519S in the North Sea and North East Atlantic Ocean.

85 CTD casts collected by Marine Scotland Science on cruise FRV Scotia 1519S in the North Sea and North East Atlantic Ocean.