assessment and analysis of a high-resolution reanalysis product for the scb oceanic circulation

Assessment and Analysis ofA High-Resolution Reanalysis Product

for the SCB Oceanic Circulation

Changming Charles Dong

Institute of Geophysical and Planetary PhysicsUniversity of California, Los Angeles

Collaborators: Eileen Y. Idica, James C. McWilliams

Acknowledgements: M.Hughes, A. Hall, C. Winant, E. Dever, L. Washburn, B. Hickey, M. Noble, C. Zhang, Y. Chao, E. Di Lorenzo, M. Blaas, LACSD

Outline

1. Introduction

2. Model Configuration and Data

3. Model Assessment

4. Dynamical Analysis (CTW, APG, Rossby Wave, Current Decomposition)

5. Summary

Pacific Ocean Los Angeles

(Strub and James, 2000, DSR)

Seasonal SST (AVHRR)and SSH (TOPEX)

SCB

CCS:

(Digiacomo and Holt, 2001)

(Digiacomo and Holt, 2001)

(Beckerbach and Washburn, 2004)

Regional Oceanic Model System (ROMS)

1. It solves the primitive equations with the oceanic currents, potential temperature, salinity and the equation of state.

It is a community model, and its source codes are open. More details, see the official website www.myroms.org

2. hydrostatic/non-hydrostatic versions

3. Application Packages: Sediment transport, Biological processes, Wave-current interaction, pollution discharge, sea ice, et al….

Regional Oceanic Model System (ROMS)

One-way nested grids(~20km ~6.7km 1km)

Surface Forcing (MM5 18km, 6km, 2 km)

Open Boundary Data (SODA, Carton et al, 2000a,b, JPO)

Levitus Climatological Data (IC)

Integration from 1996-2003

20km

6.7km

1km

Mean and Seasonal Variability

ENSO Event

Topex/Jason

Eddy Variability

1. Rossby Wave,

2. CTW, 3. APG,

4. Current Decomposition

Summary

• ROMS is employed to study the domain-scale circulation in Southern California Bight forced by MM5 and SODA.

• The model is integrated over eight-year (1996-2003)

• The mean circulation and its interannual, seasonal variability are comparable with the observations.

• Eddy variability in the SCB oceanic current system is presented.

• CTW, APG, Rossby Wave, and Current decomposition are analyzed briefly.

Current and Next Steps

1. Synoptical Scale Assessment

2. Extend the solution to the current year (2004 to 2007). and then make the reanalysis product accessible to the public online. (a proposal submitted to PISCO with D. Siegel et al)

3. Downscaling the Santa Barbara Channel (with T. Dickey)