The color of reflected light from sunlit seawater contains important information about ocean health and the amount of dissolved carbon dioxide. But taking color measurements from ships has been notoriously difficult because there is no dependable color standard for comparison.
Now PML scientists have designed and produced a sand-blasted blue tile to serve as an ocean-like reflectance sample. It is currently deployed on NOAA’s 2014 Marine Optical Characterization Cruise. This 10-day cruise with 44 planned observation points will sample the Gulf Stream and coastal waters up and down the East Coast (Charleston, SC to the Chesapeake Bay) in a sawtooth pattern.
Before deployment, PML scientists measured the reflectance of the tile using NIST’s Spectral Tri-function Automated Reference Reflectometer (STARR). The tile will be re-measured at NIST following completion of the cruise to assess the stability of the tile for use as a validation or “check” standard for ocean color measurements.