This tool visualises data collected during surveys on board the RV Cefas Endeavour, focussing on chlorophyll and phytoplankton functional types.

Separate pages are available to explore each dataset (pigments, flow cytometry, and ferrybox) separately, as well as to compare datasets. Each page has tabs for quality control of the data, plots and data download.

This tool is a work in progress. Future developments will include comparisons of phytoplankton functional types using flow cytometry and microscopy, the ability to convert ferrybox fluorescence to chlorophyll concentration. Potentially, we will also add modelled or remote sensing data


These data contain concentrations (μg/l) of the individual accessory pigments of phytoplankton measured by High Pressure Liquid Chromatography. These can be applied like a 'fingerprint' to identify phytoplankton functional types, and also used for comparison with other chlorophyll measurements by in situ fluorometers or remote sensing.

Raw data and associated metadata can be viewed on the Cefas Data Hub

These data contain information about concentration (particles/ml) and relative fluorescence (%) of phytoplankton functional types measured by flow cytometry. Flow cytometry measurement provides abundance, size and fluorescence of the phytolankton cells. During surveys on the RV Cefas Endeavour, the sea water was analysed for 10 minutes every hour by a Cytosense (Cytobuoy b.v., NL), connected to the continous flow intake at 4m depth.

Raw data and associated metadata can be viewed on the Cefas Data Hub


These data are from the RV Cefas Endeavour FerryBox (4H-JENA engineering GmbH,DE), which measures a range of parameters from the continuous flow water intake at approximately 4m depth, recording every minute.

Data is quality controlled on a per survey basis. Checks are applied for DateTime, flow rate, and GPS track. Flow lag is corrected (length of time between the intake of water and measurement) to ensure correct times and positions. Parameters are individually checked for valid range, rate of change and standard deviation. Parameters measured with multiple sensors are cross checked for consistency. Instrument calibrations are applied (fluorescence is corrected based on sensor specific fluorescent bead calibrations), and salinity is checked against bottle samples collected concurrently. Oxygen data is provided here but is known to be problematic due to interference from ship wakes.

Raw data and associated metadata can be viewed on the Cefas Data Hub


Fluorescence is in arbitrary units. Seapoint fluorometers (Seapoint Sensors, Inc., USA) on the FerryBox are standardised to a master sensor. Flow cytometry fluoresence is calibrated with beads but the units are not exactly the same. In future we hope to be able to reference both to an agreed standard (quinine sulphate).