Earlier this month the whole instrument suite went to sea together for the first time. From 7 to 9 October, in the Venice lagoon, we operated the LIFL-11 multi-wavelength LIF LiDAR, the compact MFL-12, and the passive mHR-2 radiometer side by side as part of the European Space Agency’s PHY2FLEX campaign, with vessel support from Italy’s Consiglio Nazionale delle Ricerche (CNR).
The point of the exercise was simple: confirm that instruments which perform in the laboratory also perform in real sea conditions — spray, motion, changing light. They did. All three ran through the campaign and returned clean data.
What makes the pairing useful is the combination. The mHR-2 measures above-water remote-sensing reflectance (Rrs) — the same quantity an ocean-colour satellite estimates from orbit — and on 8 October it recorded example Rrs spectra in the lagoon. At the same time and place, the active LIF sensors measured what is actually in the water. Put those two together and you have a satellite match-up: ground truth on one side, the satellite’s-eye view on the other. Producing many of those pairs in a single day is the whole idea behind our approach to cal/val.
This is the most current entry in a field record that goes back two decades. More field notes will follow as campaigns happen.