OCEAN OPTICAL SOURCE ESTIMATION WITH WIDELY SPACED IRRADIANCE MEASUREMENTS

A method was developed for determining the spatial distribution of a s ource from downward and upward irradiance measurements at a single wav elength in seawater of known optical properties. The algorithm uses me asurements at two depths located an arbitrary distance apart and solve s two nonlinear equations for two parameters that fit a globally expon ential or linear source shape. Complex spatially dependent source shap es can be estimated from an irradiance profile by piecing together est imates from neighboring measurement pairs. Numerical tests illustrate the sensitivity of the algorithm to depth, measurement spacing, chloro phyll concentration, sensor noise, and uncertainty in the a priori ass umed inherent optical properties. The algorithm works well with widely spaced measurements, moderate sensor noise, and uncertainties in the optical properties regardless of whether the assumed and true profiles are the same shape. (C) 1998 Optical Society of America.