Turbidity

Water clarity / suspended-sediment proxy. Standard operational measure is nephelometric turbidity units (NTU); satellite retrievals approximate this via the Dogliotti et al. 2015 single-band algorithm (red-band water-leaving reflectance mapped to NTU, with a near-infrared switch for high-turbidity waters), or via band-ratio indices such as NDTI (Lacaux et al. 2007, `(Red − Green)/(Red + Green)`) for relative comparison. Distinct from `chlorophyll-a-inland` — turbidity bundles sediment, plankton and CDOM together rather than isolating phytoplankton biomass. No clean GCOS parent: ocean-colour is adjacent but turbidity-specific, so this ships parentless in the operational tier. The CF standard name `sea_water_turbidity` is reused for inland waters by convention. Used by dredging-monitoring, watershed-erosion, post-flood water-quality, and EUDR-adjacent supply-chain ops.