Initial results in the development of a highly portable sensor for multi-faceted studies of ocean acidificatio.

The lowering of seawater pH due to increased anthropogenic carbon dioxide (known as ocean acidification, or OA) has received attention from scientists and lawmakers around the globe. It is generally recognized that many of the laboratories engaged in OA research do not possess the facilities or expertise necessary to measure carbon system parameters at the precision required to produce reliable, actionable results. To address this deficiency, we are developing the next evolution in carbon-system sensors. Drawing on our experience in developing and deploying our multi-parameter inorganic carbon analyzer (MICA) instruments, we will build a new system (MICA III) that will be easy to use and will require virtually no supporting infrastructure. Advances in commercial technology and refinement of our methods enables us to dramatically reduce the size and cost of MICA instrumentation. MICA III will measure three parameters: pH, dissolved inorganic carbon (DIC), and total alkalinity (TA). Our instrument will include innovative designs for temperature compensation and total alkalinity measurements and will utilize an embedded display/user interface to produce a truly portable (about the size of a large briefcase) sensor for studies of OA and environmental change. Our goal is to develop an instrument that is easily deployed by both chemists and non-chemists to produce carbon system data fully consistent with best practices protocols. In this presentation we discuss overall objectives, highlight the key elements of our initial design, and present results from laboratory calibrations and measurements using certified reference materials. We also share plans for upcoming sensor field evaluations and future development of MICA III.