Pseudo-colour images of the reef zones of the Eparses Islands, corrected for surface effects (2009-2010) — Piot and IoT Projects

These seabed images are derived from the correction of the surface effects of water on hyperspectral data acquired in 2009 and 2010 for the Litto3D Indian Ocean project (IGN/SHOM) and with funding from the Agency for Marine Protected Areas (AAMP). The calculation methods are based on developments initiated within the framework of the quadripartite cooperation agreement on the “Reef Artography of the French Islands of the Indian Ocean to Part of Hyperspectral Data” between the Prefecture of Réunion, the French Southern and Antarctic Lands, the AAMP and Ifremer. Several specific projects subsequently enabled these developments to be applied/adapted to the different geographical sub-sectors. The 2019 and 2020 processing of these hyperspectral data in the framework of the Piot and IoT projects ((pilot) project for Indian Ocean sea Turtles) generated a 4-band multispectral image (Red/Green/Bleu/PIR), improving the understanding and interpretation of some of the less obvious areas (shades, clouds, water surface artifacts, depth, etc.). The correction of surface effects, allows a better perception of the bottom in the greater depths compared to the raw hyperspectral data. On Glorieuses, these treatments resume the work initiated in the framework of the COPRA project on the mapping of grass trees in Thalassodendron (AFB/Marex). The Piot project is co-financed by the Iles Éparses Consortium2017-2020, Ifremer (carrier) and its partners (CNRS-LIRMM, Kelonia and CEDTM). The IoT project is co-financed by the ERDF-INTERREG V OI, the State, Ifremer (carrier) and its partners (CNRS-LIRMM, French Southern Lands and Antartiques, Departmental Council of Mayotte, Marin Natural Park of Mayotte, Oulanga Na Nyamba Association of Mayotte and Seychelles Islands Foundation).