Turbidity retrieval and monitoring of Danube Delta waters using multi-sensor optical remote sensing data: An integrated view from the delta plain lakes to the western–northwestern Black Sea coastal zone

Based on multi-sensor optical remote sensing techniques, more than 80 medium and high spatial resolution satellite images were used for studying the turbidity patterns of Danube Delta waters. During a selected 4-year temporal coverage (2006 to 2009), the turbidity gradients were simultaneously analyzed in the delta plain lakes and in the Black Sea western–northwestern coastal zone. Two distinct, but complementary, methodologies for retrieving turbidity were employed, one for the lakes and the other for the coastal zone. After comparing the turbidity satellite-derived turbidity products with in-situ measurements, the inter-comparability of the products was independently verified. Then, through an integrative analysis, the initial hypothesis of turbidity control by the Danube River inputs was tested in both areas (Delta plain and coastal zone). Seasonal turbidity patterns were identified together with the mechanisms responsible for its important temporal and spatial variability. Reciprocal contributions derived from the association of multi-scale satellite products were highlighted.

► Turbidity retrieval at different spatial scales from multi-sensor algorithms
► Integrated analysis of turbidity from Danube Delta plain lakes to coastal zone
► Identification of seasonal turbidity patterns and principal controlling mechanisms
► Description of spatial and temporal variability detected within the study area