Changes in pH of the global ocean can have ecosystem wide impact (coral bleaching etc.) and is identified as a ?chronic hazard? related to the carbon cycle. pH or another carbon system measurement besides pCO2 is required to completely characterize the dissolved inorganic carbon system in the ocean. ?The Global Ocean Carbon Observation System ? A Background Report? (UNESCO 2002) recommends sampling the carbonate system (DIC, alkalinity, pCO2, pH).
The PI?s with previous funding have developed a pH sensor based on a simple and robust technology that can be readily quality controlled. The SAMI-pH sensor offers a powerful method for autonomous measurements of seawater pH. The instrument can be used for inorganic carbon quantification, CO2 acidification studies, and biogeochemical process studies. The instrument may also find applications in freshwater research and monitoring and industrial monitoring
The current funding will be used to transition the SAMI-pH sensor to commercial status. The goals for this project are to: 1) Improve SAMI optical performance; 2) Minimize pH perturbation; 3) Minimize analysis time; 4) Improve ease of assembly, operation and troubleshooting; 5) Reduce power consumption; and 6) Implement in situ quality control.
Broader Impacts
Funding for this project will make an autonomous pH instrument commercially-available to oceanographers and other researchers interested in stable, accurate and precise pH measurements. By deploying the instruments in the ocean, long-term pH data will be obtained that will help the scientific community understand how CO2 absorption from the atmosphere is changing seawater pH. These results will guide policy makers charged to determine time-frames for CO2 remediation. General sensor technology developed as part of this project will benefit other research and commercial sectors that rely upon automated, high quality, chemical measurements. Post-doctoral, graduate and undergraduate students who participate in the project will increase the U.S. expertise in sensor development for environmental applications, an area of critical need.