A SeaBird SBE911Plus CTD mounted on a stainless-steel rosette was deployed at 39 different stations during RV Sonne cruise SO298 along the equatorial Pacific from Guayaquil, Ecuador to Townsville, Australia (GEOTRACES GP11 transect) during April – May 2023. The CTD was connected to the following sensors: Pressure (Digiquartz with TC), two temperature sensors (ITS90 °C), two conductivity sensors, oxygen (SBE43), PAR (Biospherical Licor Chelsea sensor), fluorometer (Wet Labs ECO-AFL/FL), turbidity (Wet Labs ECO-NTU) and an altimeter. The oxygen sensor data were calibrated against discrete water samples analysed using the Winkler method, other sensor data used factory calibrations. Sensor data from the downcast were matched with bottle closure data from the upcast.