SOMLIT-like Lanvéoc time series (French Research Infrastructure ILICO): long-term core parameter monitoring in Bay of Brest

The SOMLIT-Like -Lanvéoc time series data characterize the hydrology of the Bay of Brest, at 48°17'39"N - 04°27'09"W location. The Bay of Brest is a semi-enclosed, macro-tidal, marine ecosystem of 180 km2, connected to the Iroise Sea by a narrow and deep strait of 2 km width, and 40 m depth max. It is under the influence of the Aulne river, representing 70% of the total river discharge. Fortnightly measurements have been undertaken since January 2019 by the IUEM/UBO/CNRS-LEMAR to detect the long-term evolution of hydrology in the land-sea continuum including natural and anthropogenic forcings. The data from the Lanvéoc station are collected according to protocols established by the French monitoring network SOMLIT (, accredited by the CNRS as a national Earth Science Observatory (ILICO, The Lanvéoc station is upstream of the SOMLIT-Portzic observatory station (10.17882/91173). At the time of writing, the process of requesting SOMLIT accreditation for Lanvéoc station is underway. SOMLIT-Like-Lanvéoc samples are collected at 1m depth of a 10 m water column, at high neap tide (7m tidal range), near slack water. Samples collected are analysed for more than 20 core parameters: Sea Surface Temperature (SST), Sea Surface Salinity (SSS), dissolved oxygen (O2), pH, ammonia, nitrates, nitrites, phosphates, silicates, suspended matter, particulate organic carbone, particulate organic nitrogen, chlorophyll a, delta15N, delta13C; pico- and nano- plankton; CTD-PAR-profile. The microphytoplankton is simultaneously identified in accordance with the national PHYTOBS-network’s ( protocols. Complementary parameters are also measured for specific research studies: biogenic silica  at 1m depth and the microphytobenthos and high frequency CTDO2Fluo-measurements at sediment-water interface. The SOMLIT-Like-Lanvéoc time series data are collected in compliance with the SOMLIT network quality management system, in line with the kSO/IEC 17025:2017 standard: “General requirements for the competence of testing and calibration laboratories”. Further information on standard operating procedures for sample collection and data acquisition are available at: For more information on the quality flagging scheme:


Fisheries and aquaculture


Environmental time series, Coastal system evolution, Climate impact, Coastal ecology, Hydrological and biogeochemical data


48.349249N, 48.258585S, -4.334599E, -4.55278W


A SBE-19Plus profiler is used for CTD, PAR and Fluorescence measurements. To guarantee best performances, the sensors return to the constructor every two years for calibration.


Lanvéoc HYDRO_PiconanoPlankton_CTD Profiles_Data
51 KoCSVQuality controlled data
How to cite
Grossteffan Emilie, Delebecq Gaspard, Rimmelin-Maury Peggy, Amice Erwan, Bihannic Isabelle, Bihannic Kevin, Carlier Robin, Devesa Jérémy, Gallinari Morgane, Gromberg Theo, Lambert Christophe, Lebec Thierry, Legoff Manon, Quéré Frank, Leynaert Aude (2024). SOMLIT-like Lanvéoc time series (French Research Infrastructure ILICO): long-term core parameter monitoring in Bay of Brest. SEANOE.

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