TITLE:
Optimization of UV-Vis Spectrophotometer (OCaPI) Parameters for Measuring the pH and pCO2 of the Ocean Carbonate System in Seawater to Assess Ocean Acidification (Mediterranean Sea)
AUTHORS:
Samba Alarba Barry, Cellou Kanté, Adama Moussa Sakho, Anne-Cécile Ribou, Véronique Guglielmi, Mamadou Madaniou Sow
KEYWORDS:
Optimization, OCaPI, Carbonate System, Acidification, Ocean
JOURNAL NAME:
Open Journal of Air Pollution,
Vol.15 No.2,
May
28,
2026
ABSTRACT: Automating the measurement of carbonate system parameters is essential for improving our understanding of biogeochemical processes in marine regions. The portable OCaPI (Ocean Carbon Parameters Instrument) is designed to perform simultaneous and accurate measurements of hydrogen ion concentration (pH) and partial pressure of carbon dioxide (pCO2)1 in the ocean environment. Optimizing the parameters of the UV-Vis spectrophotometer (integration time, scan-to-average, boxcar) facilitates the quantification of ocean acidification, with significantly improved measurement accuracy and reliability. The results obtained are consistent with existing techniques and offer a simplified approach to data collection, even under challenging conditions. This work, based on design principles, performance, and preliminary results obtained in the Mediterranean Sea, paves the way for the integration of these optimized techniques into long-term monitoring programs. This will contribute to a better understanding of the impacts of climate change on marine ecosystems and to improved management in the face of ocean acidification.