HYP4NOKOUE - Applying HYPERMAQ algorithms for water quality retrieval from radiometry in the Nokoue lagoon

Context and objectives

The STEREO HYPERMAQ project aimed at using multispectral and hyperspectral remote sensing imagery to validate existing algorithms or to develop new algorithms for “non-standard” water parameters.

Among HYPERMAQ results, it has been shown that surface floating vegetation can be retrieved in very turbid waters from multispectral data, that hyperspectral remote sensing can help determining Chl-a in extreme conditions (highly turbid and eutrophic waters) and that certain phytoplankton species can be retrieved at regional level with dedicated hyperspectral or multispectral algorithm.
In this  project, we aim to test the HYPERMAQ algorithms in a new study area: the Nokoué Lagoon in order to determine their transportability to new regions.

The objectives are:

• Test other algorithms for the detection of cyanobacteria blooms as HYPERMAQ results were not conclusive on this parameter.
• Produce a Level-2 remote sensing database of optical remote sensing images from multispectral sensors: Sentinel-2 MSI, Sentinel-3. Level 1 products will be corrected for atmospheric correction with the ACOLITE software. Because for the tested parameters multispectral algorithms showed good results and because data from new hyperspectral sensors (i.e. PRISMA, ENMAP or PACE) are still in early phases of development only multispectral sensors will be used here. Indeed, data from PRISMA, ENMAP or PACE would need a substantial work to be exploited in this study and will therefore not be considered at this stage.
• Disseminate methodologies and results with users via a user workshop.