Among the many calcifying marine organisms, coccolithophores are the major producer of particulate inorganic carbon (PIC). Calcium carbonate plates covering coccolithophores, called coccoliths and released during blooms, are responsible for a large increase of the water reflectance. Aiming at investigating the spectral features of the remote sensing reflectance R_RS(λ) of marine waters during coccolithophore blooms, this study exploits the radiometric data of Ocean Color sites of the Aerosol Robotic Network (AERONET-OC) in the Western Black Sea (Galata and Gloria/Section-7) by focusing on bloom events that occurred in 2017 and 2020. The analysis, besides showing elevated R_RS(λ) in the blue-green spectral region in the presence of coccoliths, confirms a shift toward the blue of the R_RS(λ) spectra as the bloom declines and coccoliths accumulate at the surface. Results also document a decreased capability of determining the bloom state in the presence of optically complex waters such as those associated with river runoff. Finally, the comparison of satellite versus AERONET-OC radiometric data for the extreme conditions created by the presence of coccolithophores, indicates agreements between R_RS(λ) not significantly different from those previously determined for various satellite data products in the absence of appreciable concentrations of coccoliths.

在许多钙化海洋生物中，球石藻是颗粒无机碳 ( PIC )的主要生产者。覆盖球石藻的碳酸钙板，称为球石，在开花期间释放，是导致水反射率大幅增加的原因。本研究利用西黑海（加拉塔）气溶胶机器人网络（AERONET-OC）海洋颜色站点的辐射测量数据，研究了颗石藻开花期间海水遥感反射率R _RS ( λ )的光谱特征。和 Gloria/Section-7）通过关注 2017 年和 2020 年发生的绽放事件。分析，除了显示升高的R _RS ( λ) 在有石块存在的蓝绿色光谱区域中，证实了随着水华下降和石块在表面积累，R _RS ( λ ) 光谱向蓝色移动。结果还记录了在存在光学复杂水（例如与河流径流相关的水）的情况下确定水华状态的能力下降。最后，卫星与 AERONET-OC 辐射测量数据在由球石藻的存在造成的极端条件下的比较表明，R _RS ( λ )之间的一致性与先前为各种卫星数据产品确定的一致，在没有明显浓度的颗石子。