High Resolution Maps of suspended Particulate Matter Concentration in the German Bight

Abstract

Concentration of suspended particulate matter (SPM) is one of the major parameters that regulate the penetration of light into the water and hence the primary production. In this paper an algorithm for retrieving the SPM concentration from satellite borne SPOT imagery of the North Sea is introduced. For the derivation the synergy of satellite borne Modular Optoelectronic Scanner (MOS) data and SPOT imagery is used. In a first step the SPM concentrations are retrieved from the rather coarsely gridded MOS data using existing SPM algorithms for MOS data. The resulting MOS-derived SPM concentrations are used to tune an algorithm for retrieving SPM concentrations from SPOT data. Thus the tuning of this SPOT SPM algorithm is based on a synoptic and highly accurate set of satellite-derived SPM connecting the high spectral resolution of the MOS data to the high spatial resolution of the SPOT images. The high spatial resolution of SPOT images is ideally suited to measure SPM concentrations in coastal areas like the Wadden Sea in the German Bight of the North Sea, yielding the opportunity to retrieve SPM concentrations in the small water inlets of the Wadden Sea, which are needed to validate and fine tune numerical SPM models for this area. In the inlets the concentrations vary considerably between 6 and 60 mg/l as measured by SPOT. These data are compared to in situ measurements and transport models and explained by the local current and sea state situation