The capability to estimate the oceanic particulate organic carbon concentration (POC) from optical measurements is crucial for assessing the dynamics of this carbon reservoir and the capacity of the biological pump to sequester atmospheric carbon dioxide in the deep ocean. Optical approaches are routinely used to estimate oceanic POC from the spectral particulate backscattering coefficient b bp , either directly (e.g., with ba...

Since the advent of industrial manufacturing of petroleum-based plastics, their use in everyday products has become ubiquitous due to their durability, moldability, low weight, and affordability. Consequently, plastics have quickly become one of the largest components of solid waste pollution on the planet and can now be found in marine sediment, coastal waters, surface waters of oceanic gyres, and marine organisms. However, t...

Accurate estimates of the oceanic particulate organic carbon concentration (POC) from optical measurements have remained challenging because interactions between light and natural assemblages of marine particles are complex, depending on particle concentration, composition, and size distribution. In particular, the applicability of a single relationship between POC and the spectral particulate backscattering coefficient b bp (...

Measurements of the particulate volume scattering function, β p ( ψ ) , at light wavelength of 532 nm, particle size distribution, PSD, and several metrics of particulate concentration and composition were made on eight contrasting seawater samples from nearshore and coastal oceanic environments including river estuary and offshore locations. Both β p ( ψ ) and PSDs were measured on original (unfiltered) samples and particle s...