Articles | Volume 11, issue 15
Biogeosciences, 11, 4057–4075, 2014
Biogeosciences, 11, 4057–4075, 2014

Research article 01 Aug 2014

Research article | 01 Aug 2014

Free-ocean CO2 enrichment (FOCE) systems: present status and future developments

J.-P. Gattuso2,1, W. Kirkwood3, J. P. Barry3, E. Cox2,1, F. Gazeau2,1, L. Hansson4, I. Hendriks5, D.I. Kline6, P. Mahacek2,1, S. Martin8,7, P. McElhany9, E. T. Peltzer3, J. Reeve10, D. Roberts11, V. Saderne12, K. Tait13, S. Widdicombe13, and P. G. Brewer3 J.-P. Gattuso et al.
  • 1Sorbonne Universités, UPMC Univ Paris 06, Observatoire Océanologique, 06230 Villefranche-sur-mer, France
  • 2CNRS-INSU, Laboratoire d'Océanographie de Villefranche, 06230 Villefranche-sur-mer, France
  • 3Monterey Bay Aquarium Research Institute, 7700 Sandholdt Road, Moss Landing, CA 95039, USA
  • 4Ocean Acidification International Coordination Centre, IAEA-Environment Laboratories, 4a Quai Antoine 1er, 98000 Monaco, Principality of Monaco
  • 5Global Change department, IMEDEA (CSIC-UIB), Instituto Mediterráneo de Estudios Avanzados, C/ Miquel Marqués 21, 07190 Esporles (Mallorca), Spain
  • 6Scripps Institution of Oceanography, Integrative Oceanography Division, University of California, San Diego, 9500 Gilman Drive, MC 0218, La Jolla, CA 92093–0218, USA
  • 7Sorbonne Universités, UPMC Univ Paris 06, Station Biologique, Place Georges Teissier, 29688 Roscoff Cedex, France
  • 8CNRS, Station Biologique, Place Georges Teissier, 29688 Roscoff Cedex, France
  • 9Conservation Biology Division, Northwest Fisheries Science Center, National Marine Fisheries Service, National Oceanic and Atmospheric Administration, 2725 Montlake Blvd. E, Seattle, WA 98112, USA
  • 10Department of the Environment, Channel Highway, Kingston, Tasmania, Australia
  • 11Antarctic Climate and Ecosystems Cooperative Research Centre, University of Tasmania, Private Bag 80, Hobart T 7001, Australia
  • 12Benthic Ecology group, GEOMAR – Helmholtz Centre for Ocean Research in Kiel, Kiel, Schleswig-Holstein, Germany
  • 13Plymouth Marine Laboratory, Prospect Place, West Hoe, Plymouth PL1 3DH, UK

Abstract. Free-ocean CO2 enrichment (FOCE) systems are designed to assess the impact of ocean acidification on biological communities in situ for extended periods of time (weeks to months). They overcome some of the drawbacks of laboratory experiments and field observations by enabling (1) precise control of CO2 enrichment by monitoring pH as an offset of ambient pH, (2) consideration of indirect effects such as those mediated through interspecific relationships and food webs, and (3) relatively long experiments with intact communities. Bringing perturbation experiments from the laboratory to the field is, however, extremely challenging. The main goal of this paper is to provide guidelines on the general design, engineering, and sensor options required to conduct FOCE experiments. Another goal is to introduce xFOCE, a community-led initiative to promote awareness, provide resources for in situ perturbation experiments, and build a user community. Present and existing FOCE systems are briefly described and examples of data collected presented. Future developments are also addressed as it is anticipated that the next generation of FOCE systems will include, in addition to pH, options for oxygen and/or temperature control. FOCE systems should become an important experimental approach for projecting the future response of marine ecosystems to environmental change.

Final-revised paper