DataSheet1_Bio-optical properties of the Brazilian Abrolhos Bank’s shallow coral-reef waters.PDF

• Main Authors: Thais Andrade Galvão Medeiros, María Laura Zoffoli, Robert Frouin, Fábio Dall Cortivo, Gabriel Moiano Cesar, Milton Kampel
• Format: Dataset
• Language: unknown
• Published: 2022
• Subjects: Physical Geography and Environmental Geoscience not elsewhere classified; Earth Sciences not elsewhere classified; Photogrammetry and Remote Sensing; bio-optical properties; coral reef waters; shallow water model; HOPE; hyperspectral data; PRISMA; Prisma; South Atlantic Ocean
• Online Access: https://doi.org/10.3389/frsen.2022.986013.s001; https://figshare.com/articles/dataset/DataSheet1_Bio-optical_properties_of_the_Brazilian_Abrolhos_Bank_s_shallow_coral-reef_waters_PDF/21387405

The Abrolhos Bank harbors the richest coral reef ecosystem in the South Atlantic Ocean. It exhibits unique geomorphologic structures, is localized in shallow depths, and is divided into two reef regions with an inner arc close to the coast (3–20 m depth) and an outer deeper arc (5–30 m depth). This study aims to describe some bio-optical properties of the Abrolhos Bank waters and to evaluate the performance of the inversion Hyperspectral Optimization Processing Exemplar (HOPE) model, developed to retrieve optical properties in shallow waters, in the region. To this end, measurements at 75 stations during two field campaigns conducted during the 2013 and 2016 wet seasons were analyzed, and the HOPE model was applied to both in situ remote sensing reflectance (R rs ) spectra and PRecursore IperSpettrale della Missione Applicativa (PRISMA) imagery. Significant differences in optical and biological properties were found between the two arcs. The empirical relationships between chlorophyll-a concentration (Chl-a) and absorption coefficient of phytoplankton at 440 nm (a phy (440)) diverged from Bricaud’s models, suggesting differences in phytoplankton diversity and cell size. In both arcs, total non-water absorption coefficient at 440 nm (a T-w (440)) was dominated by colored dissolved organic matter (CDOM) by ∼60%. Absorption coefficient by CDOM (a cdom ) presented a higher variability within the outer arc, with the lowest contribution from non-algal particles (NAPs), and the spectral slopes of a CDOM resembled those of the inner arc. The spectral slopes of the NAP absorption coefficient suggested a dominance by organic rather than mineral particles that probably originated from biological production. The HOPE model applied to in situ R rs performed satisfactorily for depth in the Abrolhos Bank waters, although retrievals of a phy (440), CDOM plus NAP (a dg (440)) and a T-w (440) were underestimated with a relative bias of −27.9%, −32.1% and −45.8%, respectively. The HOPE model retrievals from the PRISMA image ...