Ocean Biogeochemistry || Introduction

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<ul><li><p>Introduction</p><p>Michael J. R. Fasham Hugh W. Ducklow</p><p>The Joint Global Ocean Flux Study (JGOFS) had its gen-esis in the US where a need for a programme to studythe role of the ocean in the global carbon cycle was per-ceived in the late 1980s. Peter Brewer was in the fore-front of these developments and in the Foreword he giveshis own personal view of events and the excitement gen-erated by this new global approach to ocean biogeo-chemistry.</p><p>Following the lead given by US scientists the Scien-tific Committee on Oceanic Research (SCOR) sponsoreda meeting Paris in February 1987 at which JGOFS wasborn and its main goal was defined, namely:</p><p>To determine and understand on a global scale the processes con-trolling the time varying fluxes of carbon and associated biogenicelements in the ocean, and to evaluate the related exchanges withthe atmosphere, sea floor and continental boundaries.</p><p>Later a second objective was added:</p><p>To develop a capability to predict on a global scale the responseof oceanic biogeochemical processes to anthropogenic perturba-tions, in particular those related to climate change.</p><p>The JGOFS Science Plan was developed through19891990 (SCOR 1990) and, together with the imple-mentation plan (IGBP 1992); this formed the basis ofthe JGOFS strategy. The main features were intensiveprocess studies in areas thought to make significant con-tributions to the ocean-atmosphere CO2 flux, a globalsurvey of DIC in collaboration with WOCE, and long-term time-series measurement programmes in keyocean basins. How these plans were put into practice bythe international community is described in Chap. 11.</p><p>During the period of JGOFS genesis, Alan Longhurstwas informing traditional biogeographic approaches tocharacterising large-scale ocean ecosystems, using CZCSdata (Longhurst et al. 1995). Longhursts province con-cept rests largely on the hypothesis that physical forc-ing is the primary factor governing ocean ecosystemstructure and variability. Some aspects of JGOFS stud-ies in Longhursts biogeochemical provinces are dis-cussed by Ducklow in Chap. 1, while in Chap. 2 Williamsand Follows address the key physical processes influ-encing ocean biogeochemical dynamics.</p><p>Global-scale observations of the partial pressure ofCO2 in the surface ocean and the global observations oftotal dissolved inorganic carbon obtained during JGOFShave provided an invaluable tool for understanding bothnatural and anthropogenic CO2 exchanges in the oceanand the results are discussed in Chap. 5 by Watson andOrr. In Chap. 4, Falkowski et al. summarise what hasbeen learnt about primary production during JGOFSand, perhaps more importantly for the carbon cycle, howestimates of export production might be derived fromprimary production observations.</p><p>During most of the JGOFS programme much of thescientific effort has been in the upper water column.However, the remineralisation processes in the twilightzone, the midwater column between ca. 2001 000 m, isjust as important for understanding the carbon cycleand this zone is discussed by Trguer et al. in Chap. 6.The ocean floor is the ultimate sediment trap, as well asthe site of preservation and burial of the palaeo-ocea-nographic records of past ecosystems and climate sig-nals. Deep-ocean sediment traps have been a feature ofmost JGOFS process studies, although palaeo-oceano-graphic observations have been carried out less fre-quently. Lochte et al. (Chap. 8) address these importantaspects of ocean biogeochemistry.</p><p>The role that the ocean margins play in the oceancarbon and nutrient cycles has still to be fully quanti-fied and there has been much debate about whether themargins are sources or sinks of CO2. In Chap. 3, Chen,Liu and MacDonald provide an excellent stimulus forthis work by reviewing the presently available data toderive nutrient and carbon budgets for the main shelfareas.</p><p>The time-series stations have been providing invalu-able monthly data to the JGOFS community, some since1988. A summary of the results from all the JGOFS time-series stations and a description of some of the excitingnew concepts arising from this work are given in Chap. 10by Karl et al.</p><p>Now that the observational programme is mainlycomplete, the emphasis of JGOFS has switched to ana-lysing and synthesising the vast datasets that have beenobtained. Reviews of what has been achieved during the</p><p>M. J. R. Fasham (ed.), Ocean Biogeochemistry Springer-Verlag Berlin Heidelberg 2003</p></li><li><p>2 Michael J. R. Fasham Hugh W. Ducklow</p><p>last 10 years have now been published (Fasham et al. 2001;Buesseler 2001). Two important elements of the ongoingsynthesis include modelling and projecting the effectsof climate change on ocean ecosystems and biogeochem-istry. Doney et al. assess the state of the art in ocean bio-geochemical modelling (Chap. 9), while Boyd et al. dis-cuss impacts of climate change on the ocean in Chap. 7.</p><p>Hundreds of oceanographers, students, post-docs,technicians, ships crews and officers contributed toJGOFS. The fruits of their labours are summarized here.We hope our book conveys some of the intellectual, aswell as the sometimes physical and emotional adven-ture that was JGOFS.</p><p>Acknowledgements</p><p>On the behalf of all the authors we would like to acknowl-edge the generous financial support provided by the In-ternational Council of Science (ICSU), the U.S. NationalScience Foundation (NSF), the Scientific Committee onOceanic Research (SCOR), and the International Geo-sphere-Biosphere Programme (IGBP) for this book. Wewould also like to acknowledge the aforementioned or-ganisations, the Bundesminister fr Bildung, Forschung</p><p>und Technologie (BMBF), Deutsche Forschungsgemein-schaft (DFG), the Research Council of Norway, and theUniversity of Bergen for the funding of the JGOFS Inter-national Project Office over past twelve years. Withoutthis funding the international Scientific Steering Com-mittee could not have functioned over the years and theunique international cooperation that was such an es-sential feature of this book would not have happened.Finally we would like to thank Angela Bayfield for hercareful copy editing of the manuscripts.</p><p>References</p><p>Buesseler K (2001) Ocean biogeochemistry and the global carboncycle. An introduction to the US Joint Global Ocean Flux Study.Oceanography Special Issue 14(4):1120</p><p>Fasham MJR, Balio BM, Bowles MC (2001) A new vision of oceanbiogeochemistry after a decade of the Joint Global Ocean FluxStudy (JGOFS). Ambio Special Report 10, 31 pp</p><p>IGBP (1992) Joint Global Ocean Flux Study: implementation plan.IGBP Report No 23, IGBP Secretariat, Stockholm</p><p>Longhurst A, Sathyendranath S, Platt T, Caverhill C (1995) An esti-mate of global primary production in the ocean from satelliteradiometer data. J plankton res 17:12451271</p><p>SCOR (1990) The Joint Global Ocean Flux Study (JGOFS) scienceplan. JGOFS Report No 5, Halifax Canada. Scientific Commit-tee on Oceanic Research 61 pp</p></li></ul>