A model that relates the coefficients of absorption (a) and backscattering (b b ) to diffuse attenuation (K d ), radiance reflectance (R L ), and the mean cosine for downward irradiance (μ d ) is presented. Radiance transfer simulations are used to verify the physical validity of the model for a wide range of water column conditions. Analysis of these radiance transfer simulations suggests that absorption and backscattering can be estimated with average errors of 1% and 3%, respectively, if the value of μ d is known with depth. If the input data set is restricted to variables that can be derived from measurements of upward radiance (L u ) and downward irradiance (E d ), it is necessary to use approximate values of μ d . Examination of three different approximation schemes for μ d shows that the average error for estimating a and b b increases to ∼13%. We tested the model by using measurements of L u and E d collected from case II waters off the west coast of Scotland. The resulting estimates of a and b b were compared with independent in situ measurements of these parameters. Average errors for the data set were of the order of 10% for both absorption and backscattering.
© 2003 Optical Society of America
Original Manuscript: September 9, 2002
Revised Manuscript: January 28, 2003
Published: May 20, 2003
David McKee, Alex Cunningham, and Susanne Craig, "Estimation of absorption and backscattering coefficients from in situ radiometric measurements: theory and validation in case II waters," Appl. Opt. 42, 2804-2810 (2003)