xFOCE: An open source technology consortium for ocean acidification research

The Free Ocean CO2 Enrichment (FOCE) concept and systems have been developed by the Monterey Bay Aquarium Research Institute (MBARI) as a way of performing comprehensive in situ ocean acidification (OA) seafloor experiments. MBARI funded an early project to test potential technologies for closed loop control of shifting pH associated with addition of acidified sea water, into a natural flow, stream that would manage the considerable lag times associated with the chemical reactions taking place; thus the protoFOCE was born. Later the full-scale deep water (850m depth) FOCE (dpFOCE) was tested with cabled control. We briefly outline the basic issues with OA experiments and describe why systems like FOCE are needed to better understand the impacts of OA. Early OA studies focused directly on the decreasing ability of some animals to form calcium carbonate shells under more acidic conditions. More recent work has focused on behavioral changes in marine species associated with a high CO2 environment. Each of these science studies can now be addressed by controlled in situ field experiments. Early engineering tests were published and soon external interest in the concept heightened. MBARI transferred FOCE technology to researcher working on the Great Barrier Reef. The resulting collaboration created the Coral-Prototype FOCE (cpFOCE) system. cpFOCE directly demonstrated the significant carbonate losses that may be anticipated in our “High CO2 Ocean” future. We also have the European FOCE (eFOCE), a proposal for Antarctic FOCE (antFOCE), and MBARI's own shallow water FOCE (swFOCE) with local collaborators underway. Interest in FOCE systems continues to grow as we've published and presented this capable in situ technology. To support the interested community MBARI engineering and science has developed a new concept. xFOCE is a project to create a generic FOCE reference design and to build the community support structure enabling FOCE technology to be freely available to the OA science community outside of MBARI. Within this paper we outline the technologies behind the xFOCE project and discuss the various elements of the project including decisions and ultimate goals. We also review how xFOCE can be implemented using alternate technologies if the science user chooses to do so. We outline our heavy focus on building a user group of researchers who ultimately will create and direct FOCE projects much the same as the open source software community has done with the GNU General Public License project. The distinction between “open source” and “free” is clearly articulated and we explain why this is important for building an enduring community with common standards for the execution of FOCE experiments.