POSTER SESSION 4

10:30–12:30, Thursday, September 17

Poster Session | 1 | 2 | 3 | 4 | Schedule at a Glance

ABSTRACT 1322 | POSTER 88

THE FLEX4WATER PROJECT: PHYSIOLOGY AND SPECIES MAPPING OF GLOBAL WATER PHYTOPLANKTON FROM FLEX-SENTINEL 3 SYNERGY

The ESA Earth Explorer FLEX mission is primarily aimed at advancing our knowledge on the functioning of terrestrial vegetation through retrieval of sun-induced fluorescence and energy dissipation. FLEX will embark the FLORIS instrument providing unprecedented spectral resolution (~0.3 nm) over the 500-780 nm range with moderate spatial resolution (300 m) in tandem with Sentinel-3. This synergy is critical for atmospheric correction and complementary spectral coverage. Theoretical and experimental investigations were conducted to prepare and exploit FLEX-like data to explore the potential of the FLEX mission concerning photophysiological state and species assemblage of phytoplankton. In this project, specific algorithms were developed for atmospheric correction and fluorescence retrieval based on the in-filling principle of the O2 absorption bands; this has proven essential for accurate separation of fluorescence from background radiation. Those algorithms have been applied to in situ data collected from the FLoX radiometer that mimic the spectral characteristics of FLORIS. Based on the in situ data and full radiative transfer computations, the top-of-atmosphere signal was simulated for several scenarios of water and atmosphere conditions to provide representative dataset of the synergy between Sentinel-3 and FLEX missions. Hyperspectral-based algorithms demonstrated the capability of accurately extracting sun-induced fluorescence signatures to better constrain the quantum yield of photosynthesis. Additionally, in massive bloom-conditions, fluorescence of accessory pigments were also revealed by exploitation of FLEX-like data. Based on these developments, the potentialities of the FLEX mission are presented in view of leveraging hyperspectral remote sensing of the aquatic environment related to phytoplanktonic ecosystems.

Tristan Harmel, Magellium, [email protected], https://orcid.org/0000-0002-1172-9636

Soham Mukherjee, Magellium, [email protected]

Zoé Besnard, Magellium, [email protected]

Rüdiger Röttgers, HEREON, [email protected]

Vittorio Brando, CNR, [email protected]

Mariano Bresciani, CNR, [email protected]

Pierre Gernez, Nantes Université, [email protected]

Claudia Giardino, CNR, [email protected]

Martin Hieronymi, HEREON, [email protected]

Sabine Marty, NIVA, [email protected]

Lodovica Panizza, CNR, [email protected]

Jaime Pitarch, CNR, [email protected]