Field Validation of the Low-Cost SailingBox for Reliable Ocean Monitoring in the Mediterranean

The SailingBox is a novel, reliable and user-friendly citizen-science device. Thanks to its compact, low-cost design, it can simultaneously measure up to six essential ocean variables. The SailingBox was tested on two separate sailing vessels in 2025, and here we present the preliminary results from a deployment on a Monaco Explorations sailing catamaran.

Surface water measurements were conducted in the Mediterranean Sea, in September-October 2025, during the Greece Mission, coordinated by Monaco Explorations. We deployed the SailingBox alongside a Pocket FerryBox system used for reference measurements, including temperature, salinity and pH. The resulting data provide insights into the variability of surface water properties along the boat's route from Monaco to Volos, Greece, and back. This study compares the data between the two platforms to assess the quality and consistency of the measurements, and to investigate the characteristics of the surface water dynamic during the stormy fall weather in the Mediterranean. Preliminary analysis indicates good agreement between the two measurement systems for temperature, salinity and density.

We present here the first demonstration of the citizen science version of the SailingBox on sailing vessels across variable conditions, and we demonstrate the potential of this miniaturized flow-through observation system for conducting autonomous, low-power and reliable observations in the surface coastal ocean.