SEMI-AUTOMATED PRODUCTION AND FILTERING OF SATELLITE DERIVED WATER QUALITY PARAMETERS
- 1Politecnico di Milano, Dept. of Civil and Environmental Engineering, Lecco Campus, Via Gaetano Previati 1/c, 23900, Lecco, Italy
- 2Istituto per il Rilevamento Elettromagnetico dell’Ambiente, CNR-IREA, Via Corti 12, 20133 Milano, Italy
Keywords: Water Quality Monitoring, Landsat-8 TIRS, Sentinel-3 OLCI, C2RCC, Chlorophyll-a, Total Suspended Matter, Lake Water Surface Temperature
Abstract. This paper describes the semi-automated procedure implemented for the production of Water Quality Parameters (WQP) maps obtained processing Sentinel-3 and Landsat-8 imagery in the framework of SIMILE Interreg project. The processing chain includes the use of the C2RCC processor to obtain Chl-a (Chlorophyll-a) and TSM (Total Suspended Matter) and the Barsi method to produce maps of water surface temperature. The maps were filtered to exclude anomalous values due for example to clouds, water reflection (such as glint), or mixed pixels and compared to in-situ data. The filtering included an outlier rejection performed with the 3σ rule. The values singled out as local anomalies where checked with respect to possible local behaviours, such as the presence of very small gulfs and inflow/outflow streams and providing guidelines with visual examples, to support the operator. The idea of a procedure as much as possible automated and guided is to foster the WQP maps production after the end of SIMILE project.