Particulate scattering and backscattering related to water constituents and seasonal changes in the Western English Channel

Abstract

The seasonality of the mass specific scattering and backscattering by different components of the suspended particulate matter (SPM) was investigated at a coastal station in the Western English Channel. This study considered different components of the SPM, including inorganic and organic suspended matter, chlorophyll a and six phytoplankton groups. The data set comprised a 9-year time series of observations at station L4. Scattering variability was best explained by the particulate organic matter content, with significant differences between spring -summer and autumn -winter. Particulate backscattering variability was best explained by the inorganic fraction, with no clear seasonal variation. The temporal variations of the spectral slopes of these optical properties were related to the particle composition and size distribution slope.