Instrument information:- SST (± 0.05 deg C): SST was measured with a thermosalinograph from Seabird (SBE37) which was installed in the ships moonpool next to the inlet pump at approximately 6 m depth.-Equilibrator temp (±0.05 °C): Due to a broken temperature probe, we used the temperature of an Aanderaa Optode that was placed in a continously flushed water bath next to the equilibrator. We still estimate the accuracy of teh equilibrator to 0.05 deg C.-SSS (± 0.1 PSU): SSS was measured with a thermosalinograph from Seabird (SBE37) which was installed in the ships moonpool next to the inlet pump at approximately 6 m depth.-Atmospheric press. (± 0.1 mbar): The atm. pressure was measured by the ships weather station.-Equilibrator press (± 0.1 mbar): The equilibrator is open to the atmosphere. Here we assume to have atmospheric pressure in teh equilibration chamber.-pCO2/fCO2 (±2µatm): IR sensor: Licor 6252, calibrated with 3 standard gases. Standard gases: Deuste Steininger (208.96 402 602.4), calibrated against NOAA/CMDL standard gases. Resulting uncertainty: +- 0.5 ppm. Water flow rate: 2-3 L min-1 Gas flow rate: 100 mL min-1A Weiss equilibrator was used for teh equilibration. The sample gas stream was firts dried by cooling and then with a Nafion dryer. The gas was first led to the LI-6252 for the pCO2 measurements and then through a LGR N2O analyser. The system is described in detail in Arevalo et al. (2012) and the whole setup is described in Steinhoff (2010). Surface water is pumped continuously (by a torque flow pump) from the intake to the equilibrator. The equilibrator contains a water spray head, and as the water flows through it the dissolved CO2 equilibrates with the headspace. The headspace is dried and xCO2 is determined by an infrared sensor. Calculations were performed following Pierrot (2009) and are described in detail in Steinhoff (2010). The atmospheric xCO2 values are very noisy and are reported as is.