Dissolved Inorganic Carbon (DIC) is one of four parameters measured in order to determine the marine carbonate system. The AIRICA system (Serial No. #027, Marianda, Tulpenweg 28, D-24145 Kiel) works by acidifying (2 acid strokes of 10 % phosphoric acid) a discrete sample amount (2100 µL), generating CO2. The carbon is released out of the water with the help of a carrier gas (99,999 % Nitrogen) that streams through the acidified probe (180 ml min-1). The gas flows through a NAFION dryer and Peltier cooler in order to dry the gas stream. The AIRICA system measures the CO2 concentration by using an infrared detector LICOR 7000 (LI-COR Environmental – GmbH, Siemensstrasse 25A, 61352 Bad Homburg, Germany). Once in the LICOR detector, the CO2 generates a peak, whose area is directly proportional the carbon released, allowing DIC concentration to be calculated when the exact amount of the sample is known. With the help of certified reference materials (Reference material for CO2 measurements, University of California, San Diego, Scripps Institution of Oceanography, Marine Physical Laboratory, 9500 Gilman Drive, La Jolla), previously unnoticed blank impurities can be fixed, leading to more precise measurements and more valuable data. A precision of 1.5-2 µmol kg-1 can be reached. In addition, an average of three repeated measurements is determined, with a maximum deviation of 3 µmol kg-1.