Zooplankton abundance, biovolume and biomass from Rectangular Midwater Trawl1 (RMT1) samples during POLARSTERN expedition PS106/2 to the Arctic Ocean

Mesozooplankton samples were collected with a Rectangle Midwater Trawl 1 (RMT1) during the POLARSTERN expedition PS106/2 in 2017. The net has an aperture of 1 m2 and a mesh size of 300 µm. Obliques net hauls were towed from 100 m depth to the surface. All RMT1 net samples were preserved with a buffered 4% formaldehyde seawater solution and stored at room temperature until processed in the lab. Prior to the analysis each sample was fractionated into the following size classes: 0 – 0.5 mm, 0.5 – 1 mm, 1 – 2 mm, 2 – 4 mm and >4 mm). The samples were analyzed with imaged-based ZooScan analysis (Gorsky et al. 2010) and all resulting images were taxonomically classified in the EcoTaxa dataset (https://ecotaxa.obs-vlfr.fr/prj/2534). This data collection includes individual datasets on abundance, and biovolume, biomass values derived from allometric relationships of the ZooScan image parameters, as well as direct measurements of total zooplankton dry mass.