Spatial-temporal Variations of the Total Suspended Matter Concentration in the South-eastern Baltic

The goal of the study is to examine spatial and temporal variability of total suspended matter (TSM) concentration in the surface layer of the South-eastern Baltic (SEB) based on satellite and in situ data. The TSM concentration was estimated from in situ measurements and MODIS-Aqua satellite data for 2003-2016. The maximum of TSM concentration is located alongside the coast of the Sambia Peninsula (2.5 mg/l). MODIS-derived TSM concentrations demonstrate a precise boundary between higher concentrations of particles in the coastal zone (1-2.5 mg/l) and lower values offshore (less than 1 mg/l) for the whole region during a year. There are three seasonal peaks in TSM values - April, June and August, that is associated with algae blooming. The coastal stations also show October maximum which appears to be owing to storms, forcing the coastal abrasion. Interannual variations of TSM concentration during the observation period are not significant in the offshore area, while considerable interannual variations are typical for the coastal zone. It is obvious that satellite-derived TSM data has benefits due to larger amount of data, but it shows lower annual mean TSM concentrations than in situ data.