Development of a novel hybrid pH sensor for deployment on autonomous profiling platforms

• Published in: OCEANS 2019 - Marseille
• Main Authors: Rérolle, V., Angelescu, D., Hausot, A., Ea, P., Lefèvre, Nathalie, Provost, Christine, Labaste, Matthieu
• Other Authors: Fluidion SAS, Austral, Boréal et Carbone (ABC), Laboratoire d'Océanographie et du Climat : Expérimentations et Approches Numériques (LOCEAN), Muséum national d'Histoire naturelle (MNHN)-Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Institut Pierre-Simon-Laplace (IPSL (FR_636)), École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-École polytechnique (X)-Centre National d'Études Spatiales Toulouse (CNES)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité)-École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-École polytechnique (X)-Centre National d'Études Spatiales Toulouse (CNES)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité)-Muséum national d'Histoire naturelle (MNHN)-Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Institut Pierre-Simon-Laplace (IPSL (FR_636)), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-École polytechnique (X)-Centre National d'Études Spatiales Toulouse (CNES)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité), Développement Instrumental et Techniques Marines (DITM)
• Format: Conference Object
• Language: English
• Published: HAL CCSD 2019
• Subjects: Hybrid pH sensor; microfluidic; colorimetric; electrode; acidification; [SDE.IE]Environmental Sciences/Environmental Engineering; [SDE.MCG]Environmental Sciences/Global Changes; Arctic; Ocean acidification
• Online Access: https://hal.science/hal-03027418; https://hal.science/hal-03027418/document; https://hal.science/hal-03027418/file/rerolle2019.pdf; https://doi.org/10.1109/OCEANSE.2019.8867572

International audience Ocean acidification is a direct consequence of the atmospheric CO2 increase and represents a threat for marine ecosystems, particularly in the Arctic. High-quality seawater pH measurements with good spatial and temporal coverage are required to apprehend the ocean acidification phenomena. We are working to develop a high-accuracy, high-resolution pH sensor that has the potential to allow global ocean acidification mapping through deployment on fleets of ARGO floats and other autonomous platforms already in existence. The instrument implements a novel hybrid approach, utilizing the two different and complementary measurement techniques (potentiometric and colorimetric) to generate temporally dense and highly accurate pH data. Here we present the concept and initial results obtained from a hybrid pH sensor. Results show that the potentiometric part of the sensor is capable to operate in real ocean pressure and temperature conditions, including near-freezing temperatures typical of Arctic environmental conditions. The colorimetric part provides a stable reference to perform periodic recalibrations and remove drift.