Model for separating the contributions of non-algal particles and colored dissolved organic matter to light absorption by seawater

Appl Opt. 2019 May 10;58(14):3790-3806. doi: 10.1364/AO.58.003790.

Abstract

We evaluated the performance of a recently developed absorption partitioning model [J. Geophys. Res. Oceans120, 2601 (2015)JGRCEY0148-022710.1002/2014JC010604] that derives the spectral absorption coefficients of non-algal particles, a N A P (λ), and colored dissolved organic matter, a g (λ), from the total absorption coefficient of seawater. The model's performance was found unsatisfactory when the model was tested with a large dataset of absorption measurements from diverse open-ocean and coastal aquatic environments. To address these limitations, we developed a new model based on a different approach for estimating a N A P (λ) and a g (λ) from the sum of these two coefficients, a d g (λ), within the visible spectral region. The very good overall performance of the model is demonstrated, with no tendency for bias and relatively small absolute differences (the median ≤20%) between the model-derived and measured values of a N A P (λ) and a g (λ) over a wide range of aquatic environments.