Context and objectives
Over the last decade, services for marine monitoring and management have emerged using data from medium resolution ocean colour remote sensors such as SeaWiFS, ENVISAT/MERIS and MODIS/AQUA. The success of these mainstream ocean colour sensors has stimulated the follow-up continuity missions, Sentinel-3/OCLI and VIIRS. Despite considerable advantages in coverage with respect to in situ monitoring techniques, they have critical limitations of spatial and temporal resolution (typically 300m, 1/day) with respect to user requirements. The limitation of the spatial resolution of these excludes entire end-user communities concerned with water quality monitoring for ports and estuaries and with environmental impact assessment of offshore construction, dredging and windfarm activities. The limitation of the temporal resolution has two aspects:
- Cloudiness severely affects data availability of sensors with acquisitions about once per day and
- Many tidal processes in coastal waters vary faster than the daily acquisition frequency of these sensors and so the data supplied to users may be severely contaminated by aliasing.
In the last years RBINS has overcome these limitations by designing and developing water quality products at high temporal resolution, high spatial resolution and very high spatial resolution, using sensors designed for entirely different applications (terrestrial and meteorological). This resulted in a portfolio of water quality products which dramatically improves information content of nearshore waters and improve data availability in periods of scattered or fast-moving clouds. This opens entirely new application areas including support for dredging, windfarm construction and operation, aquaculture and feature detection.
The MULTI-SYNC project aims at performing the necessary research to develop advanced ocean colour products (i.e. remote sensing reflectance, turbidity, and chlorophyll a concentration) through synergetic use of multi-scale EO data.
Expected scientific results
• Development of band shift approach to project multi-sensor remote sensing reflectance data to a common spectral band set.
• Updated tool for spatial grid standardization of multi-scale satellite data including multi-scale data reader.
• Quantification of uncertainty assessment associated with differences in spatial scales between in situ observations and satellite observations .
• Study the tidal variability in the Belgian coastal waters and its main harmonic constituents (annual cycle, daily cycle, M2 and S2 tidal components) and assess the contribution of each of these modes to the total variability of ocean colour products.
• Water quality evaluation (sediment transport and chlorophyll monitoring) to support use cases in wind farms, coastal zones, and the port of Zeebrugge based dataset for 2016-2019 processed using the adapted DINEOF approach
• Development of Multi-Scale DINEOF Synergy products by adapting DINEOF to work with several datasets with different spatial and temporal resolutions
• Synergetic analysis of multi-scale data, with uncertainty estimation to study the capabilities of DINEOF to extract multi-scale information from these datasets
Expected products and services
The functionality of the multi-scale advanced ocean colour products will be demonstrated three case studies:
- Eutrophication assessment for European Directives,
- Sediment transport monitoring near the harbour of Zeebrugge and
- Water quality monitoring in the Belgian offshore wind farms.
The water quality products will be presented to stakeholders of each case study in a dedicated workshop to stimulate product improvements based on end user feedback and ensure further infusion of earth observation products in different fields of expertise.
Federal Public Service: Health, Food Chain Safety and Environment (Belgium), RBINS-SUMO (MOMO project), University of Gent (EDULIS project).