Turbidity depends on absorption and diffusion parameters in the water column, due in particular to suspended sediment matter (SSM). Hytech-imaging offers systems for monitoring, climatology, and forecasting turbidity in coastal and offshore areas, obtained from multispectral satellite images at different resolutions, automatically, with or without in situ data, using its Secchisat© processing chain.

The Secchisat© solution is based on the measurement of diffuse attenuation parameters using the inversion of a radiative transfer model that links marine radiance to the optical properties of the constituents of the water, the seabed and the water depth. Products from the Secchisat© chain include spectral changes in diffuse attenuation, and estimates of the amount of suspended matter, turbidity in NTU, and Secchi depth. The parameters are all accompanied by a measure of associated uncertainty, estimated using a procedure for the analytical propagation of sensor errors in the processing chain.

Turbidity climatology La Rochelle Ile de Ré, first semester of 2020, based on Landsat 8 and Sentinel 2 images