Remote measurement of salinity in an estuarine environment

Abstract The microwave emission of sea water is dependent upon salinity in the low microwave spectrum and it appears possible to measure remotely surface salinity at 21cm wavelength with an accuracy up to one part salt per thousand parts water (1°/00) for a 5 – 35°/00 salinity range. The dielectric constant of sa water can be represented by that of NaCl, except the sea water conductivity is retained. The effects of the atmosphere, cosmic noise, sea surface roughness, and constant radiometer errors can be corrected using surface calibration measurements. Experiments were performed in Mississippi and Louisiana coastal waters. Salinity accuracies of 3 – 5°/00 were obtained—it is believed the accuracy was limited by the radiometer used.