Underway (Ferrybox) data collected in North West European Shelf waters from 2010 onwards dataset https://portal.medin.org.uk/portal/start.php?tpc=009_CEFAS1c58089b-616c-4375-97e8-28941d8750c1 A 4H JENA Ferrybox system runs continuously on RV Cefas Endeavour during all surveys where appropriate since 2010, generating data across the North Sea, Irish Sea, and English Channel at a resolution of one measurement per minute. A continuous inflow is taken from a dedicated inlet and pump at approximately 4m under the waterline. Key parameters measured include sea surface temperature **(SST)**, through a hull mounted temperature probe**,** salinity **(SAL),** chlorophyll fluorometry **(FLUORS)**, turbidity **(FTU),** and Photosynthetically Active Radiation **(PAR)**. Other parameters recorded include meteorological variables, oxygen concentrations, and measures of photosynthetic activity. New data is added annually. 20240718 20240409