Time-series measurement of suspended particulate matter (SPM) in turbid coastal waters

The transport of sediments is important for the coastal zone and for ecosystem functioning. The tidal inlets between the East Frisian islands connect the back-barrier intertidal flats to the North Sea. The concentrations of suspended particulate matter (SPM) in the water column are highly variable, depending on weather conditions and tides. In situ measurements were carried out at a Time Series Station in the tidal inlet between the islands of Spiekeroog and Langeoog. This study shows the suitability of multispectral transmissometry (MST) for obtaining long-term SPM measurements with high resolution.

A time series of SPM data covering nearly four months is presented. As a major result, the data reveal that a single storm surge can have less impact on SPM dynamics than longer lasting gales. This high-resolution long-term data provides background information for studying the influence of SPM dynamics on coastal sediments and for validation of satellite data.