OCMIP

Ocean Carbon-Cycle
Model Intercomparison Project

Global Analysis,Interpretation and Modelling International Geosphere-Biosphere Programme Joint Global Ocean Flux Study

Introduction

In the decade that has elapsed since 3-D ocean models were first employed to study the ocean's carbon cycle, computer technology has advanced remarkably. During that same time, more scientists have begun to employ 3-D models in efforts to improve man's understanding of ocean circulation. Others have likewise joined in, taking advantage of these developments as a means to better understand ocean biogeochemistry, which is affected largely by ocean circulation patterns.  Such models provide a test bed for ideas of how the ocean's carbon cycle operates.  They also provide tools for interpolation and prediction, both in space and time.  Yet different models can produce substantially different results.  Advances in ocean carbon-cycle modeling have been impeded by the inability to compare results because simulations and analyses differ between modeling groups.  For example, models have not been validated (compared to data) in an identical fashion.

Recognizing these hindrances as stumbling blocks which retard the development of ocean carbon-cycle models, the IGBP initiated the Ocean Carbon-Cycle Model Intercomparison Project (OCMIP) in 1995 through the Global, Analysis, Interpretation, and Modeling (GAIM) task force.  OCMIP's immediate goal is to help identify and understand differences between existing 3-D global ocean carbon-cycle models and thus speed their development.  Four such models began in 1995 to make simulations for natural and anthropogenic CO2 and C-14, following standard protocols agreed upon by participants.  Resulting output has been analyzed in a consistent manner at the OCMIP analysis center.  This was the first phase of this project, now known as OCMIP-1.

The second phase OCMIP-2 began in 1998 and will continue to the end of year 2000.  During OCMIP-2, thirteen model groups have begun participating in making new simulations for CO2 and another biogenic tracer O2, as well as for C-14 and two other circulation tracers CFC's and He-3.

Articles

Dutay, J.-C., J.L. Bullister, S.C. Doney, J.C. Orr, R. Najjar, K. Caldeira, J.-M. Champin, H. Drange, M. Follows, Y. Gao, N. Gruber, M.W. Hecht, A. Ishida, F. Joos, K. Lindsay, G. Madec, E. Maier-Reimer, J.C. Marshall, R.J. Matear, P. Monfray, G.-K. Plattner, J. Sarmiento, R. Schlitzer, R. Slater, I.J. Totterdell, M.-F. Weirig, Y. Yamanaka, and A. Yool, Evaluation of ocean model ventilation with CFC-11: comparison of 13 global ocean models. Ocean Modelling, in press, 2001.

Sarmiento, J. L., P. Monfray, E. Maier-Reimer, O. Aumont, R. Murnane and J. C. Orr, Sea-air CO2 fluxes and carbon transport: a comparison of three ocean general circulation models, Global Biogeochem. Cycles, Vol. 14, No. 4, 1267-1281, 2000.

Orr, J. C., E. Maier-Reimer, U. Mikolajewicz, P. Monfray, J. L. Sarmiento, J. R. Toggweiler, N. K. Taylor, J. Palmer, N. Gruber, C. L. Sabine, C. Le Quéré, R. M. Key, and J. Boutin, Estimates of anthropogenic carbon uptake from four three-dimensional global ocean models, Global Biogeochem. Cycles, Vol. 15, No. 1, 43-60, 2001.

  • Postscript (3.7 Mb, gzipped)
  • PDF (7.4 Mb)

    Orr, J. C., O. Aumont, A. Yool, K. Plattner, F. Joos, E. Maier-Reimer, M.-F. Weirig, R. Schlitzer, K. Caldeira, M. Wickett, and R. Matear, Ocean CO2 sequestration efficiency from 3-d ocean model comparison, in Greenhouse Gas Control Technologies, (Proceedings of the 5th Inter. Conf. on Green-house Gas Control Technologies), edited by D. Williams, B. Durie, P. McMullan, C. Paulson, and A. Smith, CSIRO, Collingwood, Australia, pp. 469-474, 2001.

  • PDF (1.3 Mb)

    Orr, J. C. and O. Aumont, 1999. Exploring the capacity of the ocean to retain artificially sequestered CO2, in Greenhouse Gas Control Technologies, edited by B. Eliasson, P. Reimer, and A. Wokaun, pp. 281--286, Elsevier Science Ltd., 1999.

    Orr, J. C., Ocean circulation and the Ocean Carbon-Cycle Model Intercomparison Project, International WOCE Newsletter, No. 35, 24--25, 1999.

    Orr, J. C. and J.-C. Dutay, OCMIP mid-project workshop, Research GAIM, 3(1), 4--5, 1999.

    Orr, J. C., Ocean Carbon-Cycle Model Intercomparison Project (OCMIP), Research GAIM, 2(2), 7, 1999.

    Orr, J. C., and R. G. Najjar, 1997. OCMIP-2 In Progress, Research GAIM, 2(1), 9, 1998.

    Orr, J. C., P. Monfray, J. L. Sarmiento, E. Maier-Reimer, J. R. Palmer, et R. G. Najjar, 1997. Transition time for ocean carbon-cycle model comparison, Research GAIM, 1(2), 8-10, 1997.

    Orr, J. C., Ocean carbon-cycle models: exploring the differences, Research GAIM, 1(1), 8-10, 1997.

    Reports

    Orr, J. C., {Ocean Carbon-Cycle Model Intercomparison Project (OCMIP): Phase 1 (1995-1997)}, GAIM Report 7, IGBP/GAIM Office, EOS, Univ. New Hampshire, Durham, NH, 1999.

    Orr, J. C., 1996 The Ocean Carbon-Cycle Intercomparison Project of IGBP/GAIM, in Ocean Storage of Carbon Dioxide, ed. W. Ormerod, IEA Greenhouse R\&D Programme, Workshop 3 -- International Links and Concerns, pp. 33-52, ISBN 1 898373 04 3, CRE Group Ltd., Cheltenham GL52 4RZ, UK

    OCMIP HOWTO Documents

    Aumont, O. and J. C. Orr, Injection-HOWTO. Internal OCMIP Report, LSCE/CEA Saclay, Gif-sur-Yvette, France, 17 pp., 1999.

    Najjar, R. and J. C. Orr, Biotic-HOWTO. Internal OCMIP Report, LSCE/CEA Saclay, Gif-sur-Yvette, France, 15 pp., 1999.

    Orr, J. C., R. Najjar, C. L. Sabine, and F. Joos, Abiotic-HOWTO. Internal OCMIP Report, LSCE/CEA Saclay, Gif-sur-Yvette, France, 25 pp., 1999.

    Orr, J. C., J.-C. Dutay, R. Najjar, J. Bullister, and P. Brockmann, CFC-HOWTO. Internal OCMIP Report,LSCE/CEA Saclay, Gif-sur-Yvette, France, 12 pp., 1999.