Unveiling Tiber River's Influence on the Tyrrhenian Coastal Ocean and Marine Bio-Optical Properties with Sentinel-2

Chlorophyll and suspended sediments are the main indicators of the marine ecosystem’s bio-optical properties. Chlorophyll is directly connected with primary productivity, while the suspended sediments are associated with water quality; both factors are influenced by climate change. The present research is mainly focused on testing the capability of Sentinel-2 on estimating the Tiber River driven spatial dynamics of chlorophyll and suspended sediment. The present research also aims to identify suitable methods for estimating chlorophyll and suspended sediment levels in the Tyrrhenian coastal ocean and seas. Algorithms including SNAP-bound C2RCC-Nets, C2X-Nets, C2X-COMPLEX-Nets, and ACOLITE-bound OC2, OC3, SPM_Nechad2010 and SPM_Nechad2016 algorithms were applied to estimate the dynamic distribution of chlorophyll and suspended sediment in the Tyrrhenian region. C2RCC-Nets outperformed all other and a statistically significant positive correlation observed with in situ-derived chlorophyll and suspended sediment, with coefficients of 0.903 and 0.966, respectively. Additionally, a positive seasonal spatial correlation was estimated between chlorophyll and suspended sediments, indicating that Tiber River discharge have positive impacts by accelerating the chlorophyll level on the Tyrrhenian coastline compared to the negative trend observed in the Mediterranean region.

• Keywords: Sentinel-2, C2RCC, chlorophyll, Suspended sediments, Tiber River, Tyrrhenian region.