资源环境科技发展态势分析平台

Coccolithophores (calcifying phytoplankton) form extensive blooms in temperate and subpolar oceans as evidenced from ocean‐colour satellites. This study examines the potential to detect coccolithophore blooms with BioGeoChemical‐Argo (BGC‐Argo) floats, autonomous ocean profilers equipped with bio‐optical and physicochemical sensors. We first matched float data to ocean‐colour satellite data of calcite concentration to select floats that sampled coccolithophore blooms. We identified two floats in the Southern Ocean, which measured the particulate beam attenuation coefficient (c_p) in addition to two core BGC‐Argo variables, Chlorophyll‐a concentration ([Chl‐a]) and the particle backscattering coefficient (b_bp). We show that coccolithophore blooms can be identified from floats by distinctively high values of (1) the b_bp/c_p ratio, a proxy for the refractive index of suspended particles, and (2) the b_bp/[Chl‐a] ratio, measurable by any BGC‐Argo float. The latter thus paves the way to global investigations of environmental control of coccolithophore blooms and their role in carbon export.