Measurements of pCO2 and turbulence from an autonomous drifting buoy in 2016 during FALKOR cruise FK161010

The buoy is equipped with a sensor to measure aqueous and atmospheric pCO2, and to monitor the increase or loss of CO2 inside the chamber. A complete cycle lasts 40 minutes, and after flushing the chamber a new cycle is initiated.

The buoy has been described in [1] and can be deployed for more than 12 hours, and at wind speeds of up to 8 m s-1. Floating chambers are known to overestimate fluxes due to the creation of additional turbulence at the water surface. We correct fluxes by measuring turbulence with two Acoustic Doppler Velocimeter: one directly underneath the center of the floating chamber, that was an Inertial motion unit (IMU) to correct for the own movement of the buoy and the other one positioned sideways to measure turbulence outside the perimeter of the buoy.