Concentrations of Chlorophyll a and phaeopigments from sectioned ice cores taken from second year sea ice during the MOSAiC (PS122) drift expedition in the central Arctic Ocean. Ice sections were pooled per depth layer, melted in filtered seawater, filtered onto precombusted GF/F filters (nominal pore size 0.7µm) and frozen at -80°C. Samples were subsequently extracted in 90°C acetone, homogenized using a cell mill, and measured on the following day using a Turner flourometer, followed by an acidification step to determine pheopigments (see Knap et al. 1994 for details and calculations). Details on sampling and processing can be found in Fong et al. 2024 (doi: 10.1525/elementa.2023.00135).