Realization of an autonomous total alkalinity sensor for surface water applications

• Main Authors: Aßmann, Steffen, Frank, C., Fietzek, Peer, Körtzinger, Arne, Linke, Peter
• Format: Conference Object
• Language: unknown
• Published: 2014
• Subjects: Ocean acidification
• Online Access: https://oceanrep.geomar.de/id/eprint/24649/

Total alkalinity (TA) is one of the four measurable parameters (TA, DIC, pH, pCO2) characterizing the carbonate system in seawater. TA is important for numerous research activities such as ocean acidification observation or carbon capture and storage (CCS) scenarios. Furthermore, TA gives precious information about many physical and biogeochemical processes such as dissolution or precipitation of calcium carbonate minerals, aerobic or anaerobic respiration as well as the mixing of water bodies. While autonomous sensors for pH and pCO2 are commercially available, there is none for TA yet that allows for measurements at sufficiently high spatial and temporal resolution. We present our latest development status of a robust and automated TA measuring system based on sample acidification and subsequent spectrophotometric pH determination. Measurement data is shown and discussed. We outline the next steps to be taken towards a fully automated, easy to use and commercially available system for discrete sample measurements and autonomous surface water applications.