Remote sensing for water quality monitoring in Maltese coastal areas

Abstract

The coastal areas of the Maltese Islands are experiencing rapid development, leading to an increased occurrence of intense, short-duration rainfall events that result in significant flooding. The problem is exacerbated by impervious surfaces in urban settings, causing runoff that carries diverse pollutants from urban and agricultural areas into coastal waters. This has pronounced detrimental effects on the region's environment and socio-economic conditions. In this study, we employed advanced remote sensing techniques to thoroughly investigate this phenomenon. Using Sentinel-2 data, our research focused on the periods before and after three major storms or weather events, aiming to quantify chlorophyll-a (CHL-A). Subsequently, we processed near real-time SENTINEL-2 imagery using the Case 2 Regional CoastColour (C2RCC) processor in SNAP to evaluate the impact of storms on coastal areas. The study's findings offer quantitative insights into the extent of chlorophyll-a and blooms following rain or storm events. The methodology and resulting products from this investigation have the potential to significantly enhance monitoring techniques, aligning with the objectives outlined in the Marine Strategy Framework Directive and Water Framework Directive.