The Regional Oceanic Modeling System

The Regional Oceanic Modeling System (ROMS)

From its inception, ROMS has been intended to be a multi-purpose, multi-disciplinary oceanic modeling tool. A major aspect of our current focus along these lines is the investigation of biogeochemical cycling and ecosystem population dynamics along the U.S. West Coast. We have presently incorporated a Nutrient-Phytoplankton-Detritus-Zooplankton (NPDZ) type model into ROMS, including an extension to represent carbon and oxygen cycling (description of the new ecosystem model, in PDF format). Such a model typically consists of the addition of several biogeochemical tracers that are advected and mixed by the model's transport schemes, undergo additional vertical movements either by sinking or specified behavioral motions, and interact with each other by biogeochemical transformations. The modularity of the ROMS code allows us to configure and explore different ecosystem model formulations, (Fasham et al., 1990; Frost, 1993; Moisan and Hofmann, 1996). What makes ROMS particularly suitable for such coupled physical-biological modeling is its K-Profile PBL surface boundary layer parameterization scheme (KPP) and its tolerance for highly stretched vertical grids (due to the vertical-spline discretization), used to efficiently enhance the resolution near the surface where most of the biological activity takes place. We currently are computing equilibrium U.S. West Coast (USWC) with ecosystem dynamics and exploring the sensitivity to different model types and parameters.

There is also a 1D adaptation of ROMS (by Pierrick Penven).

The latest version of ROMS with embedding uses the AGRIF library.

Chlorophyll-a concentrations Top: SeaWIFS Ocean Color satellite image of Monterey Bay. This image was captured on May 17, 1998.
Bottom: Results of a ROMS simulation with the US West Coast model. Shown are chlorophyll-a concentrations in spring. The horizontal resolution of this model is 5 km.

	Top: SeaWIFS Ocean Color satellite image of Monterey Bay. This image was captured on May 17, 1998. Bottom: Results of a ROMS simulation with the US West Coast model. Shown are chlorophyll-a concentrations in spring. The horizontal resolution of this model is 5 km.

References

Fasham, M.J.R., H.W. Ducklow, and S.M. McKelvie, A nitrogen-based model of plankton dynamics in the oceanic mixed layer. J. Geophys. Res., 48, 591-639, 1990.

Frost, B.W., A modeling study of processes regulating plankton standing stock and production in the open subarctic Pacific Ocean. Prog. Oceanogr., 32, 17-56, 1993.

Moisan, J.R. and E.E. Hofmann, Modeling nutrient and plankton processes in the California coastal transition zone. 1. A time- and depth-dependent model. J. Geophys. Res., 101, 22,647-22,676, 1996.

Publications

Gruber, N., H. Frenzel, S. C. Doney, P. Marchesiello, J. C. McWilliams, J. R. Moisan, J. J. Oram, G.-K. Plattner, and K. D. Stolzenbach, Eddy-resolving simulation of plankton ecosystem dynamics in the California Current system, Deep-Sea Res. I, 53, 1483-1516 (pdf file of full article available upon request).

Plattner, G.-K., N. Gruber, H. Frenzel, and J. C. McWilliams, Decoupling marine export production from new production, Geophys. Res. Lett., 32, L11612, doi:10.1029/2005GL022660, 2005.

Shchepetkin, A.F. and J.C. McWilliams, 2004: The regional oceanic modeling system (ROMS): a split-explicit, free-surface, topography-following-coordinate oceanic model. Ocean Modelling, 9, 347-404.

Capet, X. J., P. Marchesiello, and J. C. McWilliams, Upwelling response to coastal wind profiles, Geophys. Res. Lett., 31, L13311, doi:10.1029/2004GL020123, 2004.

Report about ROMS in NCSA's Access Magazine, 2003.

Marchesiello, P., J. C. McWilliams, and A. Shchepetkin, Equilibrium Structure and Dynamics of the California Current System. J. Phys. Oceanogr., 33, 753-783, 2003.

Shchepetkin, A. F. and J. C. McWilliams, A method for computing horizontal pressure-gradient force in an oceanic model with a nonaligned vertical coordinate. J. Geophys. Res., 108(C3), 3090, doi:10.1029/2001JC001047, 2003.

Marchesiello, P., J. C. McWilliams, and A. Shchepetkin, Open boundary conditions for long-term integration of regional oceanic models. Ocean Modelling, 3, 1-20, 2001.

Presentations

Frenzel, H., A. Leinweber, N. Gruber, R. F. Shipe, and J. C. McWilliams, Modeling the Seasonal Decoupling of the Carbon and Nitrogen Cycles in Santa Monica Bay, CA. Presented at Ocean Sciences Meeting, Honolulu/HI, February 23, 2006. (MS Powerpoint, 0.6 MB; abstract in HTML)

Jin, X., N. Gruber, and H. Frenzel, The Impact of Patch Size and Duration on the Efficiency of Iron Fertilization: Results From an Eddy-permitting Model. Presented at Ocean Sciences Meeting, Honolulu/HI, February 22, 2006. (MS Powerpoint, 0.4 MB; abstract in HTML)

Gruber, N., Modeling the coastal carbon cycle in the global context: Challenges and surprises. Presented at Gordon Research Conference on Chemical Oceanography, Tilton/NH, August 9, 2005. (MS Powerpoint, 3.5 MB)

Plattner, G.-K., N. Gruber, H. Frenzel, and J. C. McWilliams, Decoupling of Export From New Production. Presented at ASLO Summer Meeting 2005, Santiago de Compostela/Spain, June 20, 2005 (Session: SS08 - Carbon and Carbonate Fluxes in the Coastal Ocean). (MS Powerpoint, 1.1 MB; abstract in HTML)

Gruber, N., H. Frenzel, J. C. McWilliams, G.-K. Plattner, and P. Marchesiello, The impact of eddies on coastal ocean productivity and biogeochemistry. Presented at ASLO Summer Meeting 2005, Santiago de Compostela/Spain, June 20, 2005 (Session: SS08 - Carbon and Carbonate Fluxes in the Coastal Ocean). (MS Powerpoint, 3 MB; abstract in HTML)

Frenzel, H., N. Gruber, J. C. McWilliams, and G.-K. Plattner, Simulation of plankton ecosystem dynamics and upper ocean biogeochemistry in the California Current system. Presented at AGU Fall Meeting 2004, San Francisco/California, December 17, 2004 (OS54A-03). (MS Powerpoint, 2.7 MB; abstract in HTML; presentation includes AVI animations 1, 2, and 3)

Plattner, G.-K., H. Frenzel, N. Gruber, and J. C. McWilliams, Decoupling of Export From New Production: The Role of Lateral Transport. Presented at AGU Fall Meeting 2004, San Francisco/California, December 17, 2004 (OS54A-04). (abstract in HTML)

Plattner, G.-K., The coastal carbon cycle challenge. Presented at Scripps Insitution of Oceanography (Marine chem-geochem-geosciences seminar), San Diego/California, October 18, 2004. (MS Powerpoint, 2.3 MB)

Frenzel, H., N. Gruber, X. Capet, P. Marchesiello, and J. C. McWilliams, Modeling of an Upwelling Event and its Effects on Biogeochemical Cycles in Santa Monica Bay, California. Presented at AGU Ocean Sciences Meeting, Portland/Oregon, January 30, 2004 (OS52I-03). (MS Powerpoint, 3.6 MB; abstract in HTML )

Plattner, G.-K., H. Frenzel, N. Gruber, A. Leinweber, J. C. McWilliams, P. Marchesiello, G. E. Friederich, and F. P. Chavez, Physical-Biogeochemical Interactions and CO₂ Air-Sea Exchange Along the U.S. West Coast. Presented at AGU Ocean Sciences Meeting, Portland/Oregon, January 30, 2004 (OS51L-01). (MS Powerpoint, 0.8 MB; abstract in HTML)

Plattner, G.-K., H. Frenzel, N. Gruber, A. Leinweber, P. Marchesiello, J. C. McWilliams, G. E. Friederich and F. P. Chavez, The influence of mesoscale processes on the dynamics of the upper ocean carbon cycle along the U.S. West Coast. Presented at Eastern Pacific Ocean Conference (EPOC), Catalina/California, September 25, 2003. (MS Powerpoint, 0.8 MB; abstract in HTML)

Posters

Lachkar, Z., N. Gruber, G.-K. Plattner, H. Frenzel, and M. Muennich, Ocean carbon cycling in Eastern Boundary Current systems: the Canary vs the California Current System. Presented at ROMS/TOMS Workshop at UCLA, October 2007.

Plattner, G.-K., T. Nagai, N. Gruber, H. Frenzel, and J. C. McWilliams, Ocean carbon cycling and CO2 air-sea exhange along the U.S. West Coast. Presented at ROMS/TOMS Workshop at UCLA, October 2007.

Jin, X., N. Gruber, H. Frenzel, S. C. Doney, and J. C. McWilliams, The impact on atmospheric CO₂ of changes in the ocean's biological pump. Presented at the Ocean Carbon and Biogeochemistry (OCB) Workshop in Woods Hole/MA, July 2007.

Deutsch, C., N. Gruber, H. Frenzel, T. Nagai, G.-K. Plattner, J. McWilliams, A. Leinweber, F. Chavez, K. Stolzenbach, G. Friederich, B. Hales, S. Doney, Carbon fluxes, transformations, and transports along the North American margin: A multi-scale modeling assessment. Presented at the U.S. North American Carbon Program (NACP) Investigators Meeting, Colorado Springs/CO, January 2007.

Dong, C., W. P. Budgell, H. Zhang, Y. Chao, and J. C. McWilliams, Preliminary Analysis of Sea-Ice Variation and Oceanic Current in the Bering Sea. Presented at the Alaska Marine Science Symposium, Anchorage/AK, January 2007.

Dong, C., J. Peng, H. Zhang, J. McWilliams, and K. Stolzenbach, Numerical simulation of DDTs Distribution in the Southern California Bight. Presented at California and the World Ocean '06, Long Beach/CA, September 2006.

Frenzel, H., C. Dong, N. Gruber, and J. C. McWilliams, Modeling of a coastal upwelling event in the Southern California Bight. Presented at California and the World Ocean '06, Long Beach/CA, September 2006.

Plattner, G.-K., T. Nagai, N. Gruber, H. Frenzel, and J. C. McWilliams, Ocean carbon cycling and CO₂ air-sea exchange along the U.S. West Coast. Presented at EGU (European Geosciences Union) General Assembly 2006, Vienna/Austria, April 2006.

Nagai, T., N. Gruber, H. Frenzel, and J. C. McWilliams, Offshore Biogeochemical Fluxes in the California Current System: The Importance of Eddies. Presented at AGU Ocean Sciences Meeting, Honolulu/HI, February 2006.

Jin, X., H. Frenzel, and N. Gruber, Iron fertilization efficiency: Results of an eddy-permitting model. Presented at Ocean Carbon and Climate Change (OCCC) Workshop, Woods Hole/MA, August 2005.

Plattner, G.-K., N. Gruber, H. Frenzel, and J. C. McWilliams, Decoupling export from new production in the central California upwelling system. Presented at Ocean Carbon and Climate Change (OCCC) Workshop, Woods Hole/MA, August 2005.

Frenzel, H., C. Dong, M. Blaas, P. Marchesiello, and J. C. McWilliams, Modeling of an Upwelling Event and its Effects on Biogeochemical Cycles in Santa Monica Bay, California. Presented at ROMS/TOMS Workshop in Venice/Italy, October 2004.

Plattner, G.-K., H. Frenzel, N. Gruber, A. Leinweber, and J. C. McWilliams, Changing winds and coastal carbon cycle: A case study for an upwelling region. Presented at SCOR conference "The ocean in a high CO₂ world", Paris/France, May 2004. (SCOR: UNESCO Scientific Committee on Oceanic Research)

Blaas, M., P. Marchesiello, J. C. McWilliams, and K. D. Stolzenbach, Sediment-transport modeling on Southern California Shelves. Presented at AGU Ocean Sciences Meeting, Portland/OR, January 2004.

Plattner, G.-K., H. Frenzel, N. Gruber, A. Leinweber, P. Marchesiello, J. C. McWilliams, G. E. Friederich, and F. P. Chavez, Dynamics of CO₂ air-sea gas exchange along the U.S. West Coast. Presented at Final JGOFS Meeting, Washington/DC, May 2003.

Frenzel, H., N. Gruber, P. Marchesiello, and J. C. McWilliams, Influence of meso- and submeso-scale variability on biological productivity along the U.S. West Coast. Presented at AGU Fall Meeting, San Francisco/CA, December 2002.

Gruber, N., H. Frenzel, P. Marchesiello, and J. C. McWilliams, On the role of transport in decoupling export from new production. Presented at JGOFS PI Meeting, July 2002.

People at UCLA working on and with ROMS

Maarten Buijsman, Francois Colas, Charles Dong, Hartmut Frenzel, Nicolas Gruber, Edward Huckle, Eileen Idica, Xin Jin, Jaison Kurian, James C. McWilliams, Alexander F. Shchepetkin, Keith D. Stolzenbach, Yusuke Uchiyama

Former UCLA ROMS people:

Meinte Blaas, Xavier Capet, Yulia Kanarska, Patrick Marchesiello, Takeyoshi Nagai, John J. Oram, Gian-Kasper Plattner, Carrie Zhang