Abundance of microbial bacteria and phytoplankton through the water column during the AMT30 (DY157) cruise in February-March 2023

This dataset contains depth profiles of the mean abundance of groups of plankton as cells per millilitre, measured using flow cytometry from research cruise AMT30 (DY157) in February-March 2023. Bacteria and phytoplankton were analysed from all depths to a maximum of 200 m. Samples were collected using a Seabird rosette sampler containing 20 L Niskin bottles and analysed within 3 hours of being taken. The groups quantified are divided into phytoplankton and heterotrophic bacteria. Phytoplankton groups quantified are: Synechococcus sp., Prochlorococcus sp. (cyanobacteria), picoeuakryotes (smaller than 2 μm), cryptophytes, coccolithophores, and nanoeukaryotes (Neuk) not already mentioned (2-20 μm). Heterotrophs quantified are: bacteria with relatively high nucleic acid content (HNA) and bacteria with relatively low DNA.