The ships4sst: FRM4SST project provides in situ SST data using Fiducial Reference Measurements (FRM) that are used to validate Copernicus Sentinel-3A and Sentinel-3B SLSTR SST data. We do this by collecting, processing, analysing, publicising and reporting in situ FRM field measurements made using ISAR and SISTeR instruments. These instruments are near-contemporaneous with satellite data from the SLSTR-A and SLSTR-B instruments. Click here for more information about the ISAR and SISTeR instruments.

Providing reliable, traceable and timely FRMs to support the validation of SLSTR SST involves the use of three unique European activities and data sets:

1. Continuation of the ISAR 002 and 003 radiometer deployments in the English Channel and Bay of Biscay by the University of Southampton, involving:

  • ISAR instrument operation on the Pont Aven or equivalent ferry,
  • Quality assurance of ISAR data, including pre- and post-deployment laboratory validations,
  • ISAR instrument maintenance.

2. Continuation of SISTeR A deployments by STFC RAL Space on the Queen Mary 2 liner between Southampton and New York, and round the world, involving:

  • Regular deployments of a single SISTeR radiometer on the Queen Mary 2 liner to collect radiometric measurements of the sea surface,
  • Validating the radiometric calibrations of the SISTeR radiometers before and after every deployment, following best practice,
  • SISTeR instrument maintenance.

3. Deployment of ISAR 008 by DMI on a Smyril-line ship between Denmark - Faroe Islands - Iceland, in synergy with the Ferrybox project and instrumentation, involving:

  • Regular deployments of an ISAR radiometer on the Norröna passenger ferry or equivalent to collect radiometric measurements of the sea surface,
  • Validating the radiometric calibrations of the radiometer against a blackbody reference before and after every deployment, following best practice,
  • ISAR instrument maintenance.

The SST FRM products will be ISAR and SISTeR data in L2R format with calibrated skin SST and associated uncertainties. In addition, match-up data will be provided between the SST FRM products and satellite data, principally SLSTR-A and SLSTR-B, using the Felyx tool hosted by Ifremer.

Data are now available online and can be accessed on account after completing a simple registration form. We also encourage anyone with data to share them through this website. Please contact us if you require more information on sharing data.