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We provide an analysis of zooplankton distributions in the circumpolar Southern Ocean based on samples collected by the international SCAR Southern Ocean Continuous Plankton Recorder Survey (SO-CPR). We analysed SO-CPR measurements in relation to satellite and oceanographic model hind-cast data over the period 1997–2018. These environmental data were chlorophyll-a concentration, net primary productivity (VGPM model), sea-surface temperature (SST), mixed layer depth, sea ice and the spatial gradient of SST (as an indicator of ocean fronts). Boosted Regression Tree (BRT) models were used to extrapolate in space and time measurements of the abundances of six key taxonomic groups of zooplankton: Copepoda (Calanoida), Euphausiidae (numerically dominated in SO-CPR data by Thysanoessa macrura), Foraminifera, Fritillaria spp., Oithona similis, and pteropods. Based on the BRT models …