Oceanographic underway data were collected by the FerryBox on board RV POLARSTERN. The system is supplied by a sea water inlet at about 5 meters depth. As part of the MOSAiC project, cruise PS122/1 is located within the arctic ocean. Measured oceanographic parameter are water temperature (Seabird, SBE45), conductivity (Seabird, SBE45), dissolved oxygen (Anderaa Optode) and turbidity (Cyclops-7F Turbidity Sensor). Salinity was calculated from temperature and conductivity measurements. Published here is also the main flow of the system as a control parameter for measurement quality. No calibration corrections were done for the parameters. Quality flagging of the parameters is described in the attached data processing report.