Oceanographer at NOAA's Geophysical Fluid Dynamics Laboratory.
Formerly of Prior Lake, the University of Chicago, and the University of Washington School of Oceanography.
GFDL's primary ocean model development efforts have shifted to work on the "Generalized Ocean Layer Dynamics" (GOLD) model. GOLD is intended to be the vehicle for the consolidation of all of the ocean model development efforts at GFDL, including both MOM and HIM. The initial version of GOLD is based on HIM, and will reproduce many HIM solutions. The final version of MOM has just been publicly released, and the most significant MOM capabilities will be transitioned over to the GOLD code base over the next few years. A publicly accessible web page describing GOLD, along with instructions how to access it, will be forthcoming soon.
I spent many years developing the Hallberg Isopycnal Model (HIM). This model wass so named because (1) my wife is in marketing, and (2) it entirely describes what this model is: it uses an isopycnal vertical coordinate, and R. Hallberg is entirely responsible for its existence. This model was initially based on the Arakawa and Hsu (Mon. Wea. Rev., 1990) isentropic coordinate atmospheric model, but it has been extensively modified for use as an ocean model. HIM has evolved to the point where it includes reasonably accurate depictions of all of the physical processes that are important for the large-scale ocean circulation, although it can also be easily configured as an idealized model for Geophysical Fluid Dynamics Studies. More details are available at the HIM web page. HIM is available by contacting Bob Hallberg at Robert.Hallberg@noaa.gov.
Through the project Modeling Eddies in the Southern Ocean (MESO), we have examined the role of transient eddies in the dynamic and watermass balances in the Southern Hemisphere with a series of increasingly high resolution primitive equation model simulations using HIM. The profound qualitative impact of changing resolution can be seen in this 19Mb animation of the surface speed from two of the MESO models. Full details are given in Hallberg and Gnanadesikan (2006).
We are actively developing a 1-degree HIM/GOLD-based global ocean model for IPCC-class climate studies. The preliminary indicatations are that this model will reproduce the observed circulation with reasonable fidelity, at a computational expense that is dramatically lower than for more commonly used ocean-components of climate models. This difference in cost is particularly pronounced when many passive tracers are used.
I am actively involved in two Climate Process Teams - one studying Gravity Current Entrainment, and the other examining Eddy-Mixed Layer Interactions. These teams aim to improve the the representation of these processes in climate-scale models, based on the best understanding that can be obtained from observations, process studies, and theory.
Fox-Kemper, B., R. Ferrari, and R. Hallberg, 2008: Parameterization of mixed layer eddies. I: Theory and diagnosis, J. Phys. Oceanogr., 38, 1145-1165.
Harrison, M., and R. Hallberg, 2008: Pacific subtropical cell response to reduced equatorial mixing, J. Phys. Oceanogr., in press.
Jackson, L., R. Hallberg, and S. Legg, 2008: A parameterisation of shear-driven turbulence for ocean climate models, J. Phys. Oceanogr., 38, 1033-1053.
Little, C. M., A. Gnanadesikan, and R. Hallberg, 2008: Large scale oceanographic constraints on the distribution of melting and freezing under ice shelves, J. Phys. Oceanogr., in press.
Anderson, W. G., A. Gnanadesikan, R. Hallberg, J. Dunne, and B. L. Samuels, 2007: Impact of ocean color on the maintenance of the Pacific Cold Tongue, Geophys. Res. Lett., 34, L11609, doi:10.1029/2007GL030100.
Legg, S., L. Jackson, and R. Hallberg, 2007: Eddy-resolving modeling of overflows. In Eddy-resolving Ocean Modeling, M. Hecht and H. Hasumi eds., AGU, in press.
Hallberg, R., and A. Gnanadesikan, 2006: The role of eddies in determining the structure and response of the wind-driven Southern Hemisphere overturning: Results from the Modeling Eddies in the Southern Ocean (MESO) project. J. Phys. Oceanogr., 36, 2232-2252.
Kunkel, C. M., R. W. Hallberg, and M. Oppenheimer, 2006: Coral reefs reduce tsunami impact in model simulations, Geophys. Res. Lett., 33, L23612, doi:10.1029/2006GL027892.
Adcroft, A., and R. Hallberg, 2006: On methods for solving the oceanic equations of motion in generalized vertical coordinates. Ocean Modelling, 11, 224-233.
Legg, S., R. W. Hallberg, and J. B. Girton, 2006: Comparison of entrainment in overflows simulated by z-coordinate, isopycnal and non-hydrostatic models. Ocean Modelling, 11, 69-97.
Hallberg, R., 2005: A thermobaric instability of Lagrangian vertical coordinate ocean models. Ocean Modelling, 8, 279-300.
Arbic, B. K., S. T. Garner, R. W. Hallberg, and H. L. Simmons, 2004: The uses and accuracy of a forward global tide model: Effects of topographic drag, self-attraction and loading, and stratification. Deep-Sea Research II, 51, 3089-3101.
Simmons, H. L., R. W. Hallberg, and B. K. Arbic, 2004: Internal wave generation in a global baroclinic tide model. Deep-Sea Research II, 51, 3043-3068..
Hallberg, R., 2003: The suitability of large-scale ocean models for adapting parameterizations of boundary mixing and a description of a refined bulk mixed layer model. Proceedings of the 2003 Aha Hulikoa Hawaiian Winter Workshop, U. Hawaii, 187-203.
Papadakis, M. P., E. P. Chassignet and R. W. Hallberg, 2003: Numerical simulations of the Mediterranean Sea outflow: impact of the entrainment parameterization in an isopycnic coordinate ocean model. Ocean Modelling, 5, 325-356.
Gnanadesikan, A., and R. W. Hallberg, 2002: Physical Oceanography- Thermal Structure and General Circulation. Encyclopedia of Physical Sciences and Technology, 3rd Ed., 12: 189-210.
Thompson, L., K. A. Kelly, D. Darr, and R. Hallberg, 2002: Buoyancy and mixed-layer effects on the sea surface height response in an isopycnal model of the North Pacific. J. Phys. Oceanogr., 32, 3657-3670.
Hallberg, R., 2001: Reply (to comments on "Localized coupling between surface- and bottom-intensified flow over topography"). J. Phys. Oceanogr., 31, 1926-1930.
Hallberg, R., and A. Gnanadesikan, 2001: An exploration of the role of transient eddies in determining the transport of a zonally reentrant current. J. Phys. Oceanogr., 31, 3312-3330.
Hallberg, R., and J. McWilliams, 2001: Objective 9: To improve numerical models for the diagnosis, simulation, and prediction of the general circulation of the ocean. 2001 U.S. WOCE Implementation Report, 13, U. S. WOCE Office, 60-64.
Hallberg, R., and P. B. Rhines, 2000: Boundary sources of potential vorticity in geophysical circulations. In Developments in Geophysical Turbulence, R. M. Kerr and Y. Kimura, eds., Kluwer, 51-65.
Hallberg, R., 2000: Time integration of diapycnal diffusion and Richardson number dependent mixing in isopycnal coordinate ocean models. Mon. Wea. Rev., 128, 1402-1419.
Gnanadesikan, A., and R. Hallberg, 2000: On the relationship of the circumpolar current to Southern Hemisphere winds in large-scale ocean models. J. Phys. Oceanogr., 30, 2013-2034.
Griffies, S. M., and R. Hallberg, 2000: Biharmonic friction with a Smagorinsky-like viscosity for use in large-scale eddy-permitting ocean models. Mon. Wea. Rev., 128, 2935-2946.
Griffies, S. M., R. Pacanowski, and R. Hallberg, 2000: Spurious diapycnal mixing associated with advection in a Z-coordinate ocean model. Mon. Wea. Rev., 128, 538-564.
Winton, M., R. Hallberg, and A. Gnanadesikan, 1998: Simulation of density-driven frictional downslope flow in Z-coordinate models. J. Phys. Oceanogr., 28, 2163-2174.
Hallberg, R., 1997: Stable split time stepping schemes for large-scale ocean modeling. J. Comp. Phys., 135, 54-65.
Hallberg, R., 1997: Localized coupling between surface and bottom intensified flow over topography. J. Phys. Oceanogr., 27, 911-988.
Hallberg, R., and P. Rhines, 1996: Buoyancy-driven circulation in an ocean basin with isopycnals intersecting the sloping boundary. J. Phys. Oceanogr., 26, 913-940.
Hallberg, R., 1995: Some Aspects of the Circulation in Ocean Basins with Isopycnals Intersecting the Sloping Boundaries. Ph. D. Thesis, University of Washington. 244 pp.
Hallberg, R., and A. K. Inamdar, 1993: Observations of seasonal variations in atmospheric greenhouse trapping and its enhancement at high sea surface temperature. J. Climate, 6, 920-931.
Dr. Robert Hallberg
NOAA/GFDL
Princeton University
Forrestal Campus, U.S. Route 1
P.O. Box 308
Princeton, NJ 08542
Bob Hallberg
99 Lakeside Dr. N.
Piscataway, NJ 08854
E-mail: Robert.Hallberg@noaa.gov
Home Phone: (732) 463-1274
FAX: (609) 987-5063
Work Phone: (609) 452-6508
This page last updated Feb. 2004