Method for the determination of the index of refraction of particles suspended in the ocean*

It is shown that the complex index of refraction of a given particle-size distribution may be calculated if the particle extinction coefficient and the particle absorption coefficient are known. If the particles are assumed to be nonabsorbing, a real index of refraction may be calculated from the ratio of light scattering at 45° from the forward for two wavelengths. Application of the method to two stations off Ecuador indicates that the particle index of refraction can be determined with sufficient accuracy to become an important parameter in the study of the oceans.