Monitoring water quality parameters in the marine area of Danube Delta using satellite remote sensing: preliminary results

The aim of this work was to produce water quality parameter maps for the marine area of the Danube Delta using remotely sensed data and to validate the results with in-situ measurements. For this reason, satellite images from ENVISAT/MERIS and Aqua/MODIS were used along with collocated in-situ measurements. The latter were in-sync with the satellite images acquisition so that rigorous and validation could be performed. Chlorophyll-a concentration and total suspended matter were estimated using the CASE-II algorithm and MERIS satellite images, while sea surface temperature was estimated from MODIS Ocean Team products. The results show that the satellite images covered the study area completely, with some data gaps due to cloud coverage. Comparisons show a good correspondence with in-situ measurements. Thus, the time series of satellite images that was produced suggests that it is possible to monitor the biological changes on an operational basis. The produced maps described a detailed spatial pattern of chlorophyll-a and total suspended matter that could not have been identified from the sparse in-situ measurements.