Where flow-through systems average, we resolve

Most regulatory monitoring of European waters runs on two instruments, flow-through sampling on research vessels and bio-optical retrievals from satellites. The first returns one point every several minutes; the second views the water through about 100 km of atmosphere, where up to 90% of the recorded signal is atmosphere rather than water. Neither resolves the sub-metre variability that drives an algal bloom, defines the boundary of a hydrocarbon spill, or distinguishes a treated outflow plume from background coastal water.

A LIF lidar closes that gap by carrying its own light source to the water, which is also why it works through the night. Mounted on a motorboat, glider, drone, or autogyro, the LIFL-11 records the full 48-band echo spectrum of the upper water layer in about fifteen seconds at a station, or streams four selected bands at up to 10 Hz underway, which puts up to 20 measurements inside a single Sentinel-2 pixel at 10 kn. Run against a satellite overpass, one measurement day returns thousands of synchronous pairs of true in-water concentration and the reflectance the satellite sees, at a match-up density no flow-through system reaches.

LIFeLiDAR runs this work inside the funding and regulatory architecture that already needs it. OQOMETHI, funded by France 2030 through ADEME's Innov'Eau call, puts up to 1,000 micro-observatories on French lakes, rivers, and coastal lagoons, mounted above the water on structures that already exist and reading chlorophyll-a, suspended sediment, and dissolved organic matter day and night. SubseaLIF takes the same physics into the water column, at depths to 6000 m, after the hydrocarbon leaks and wastewater discharge that no remote method reads before they surface. In both, our workpackage is the sensors. What they measure is already mandated: chlorophyll-a and transparency on continental water under the Water Framework Directive, eutrophication and contamination at sea under the Marine Strategy Framework Directive's D5 and D8 descriptors, and in-situ ground truth for calibrating the Copernicus missions overhead.