1. A QUASI-GLOBAL CONFIGURATION OF ROMS (OR, TOWARDS GOMS?) Guillermo Auad & Art Miller (CRD/SIO) Grid features : ● zonal resolution: 0.8º (fixed); meridional resolution: 0.3 to 0.7º (slowing varying: ∆ resolution < 1.5%); vertical resolution: 20 levels. ● Includes: fixed Iceshelf, topography from etopo2. ● Zonal walls at 80º (N & S). ● E-W periodic condition used at longitude 180º. Runs carried out so far: 1.- Spin up climatological run from rest and Levitus T-S. (60-year long) driven by NCEP/NCAR reanalysis wind stresses and heat fluxes. 2.- 56-year long hindcast run (i.e., climat. + anomalous winds and heat fluxes), from 1948 to 2003 (finished a few days ago).

2. Organization A minor code adaptation Spin up of the model's total kinetic energy Model output: main ocean currents of the World A tough test: coastal flows A tougher test: representation of a water mass: NPIW 2 climatic indexes in the Pacific Ocean: PDO and Nino3.4 Planned applications

3. Scaling of horizontal viscosity coefficient goal: for each grid cell to proportionally (to its grid size) contribute potential vorticity to western boundary layers. ß ψ x ~ A h ψ xxxx (1) but since A h needs to satisfy a minimum value in order to yield realistic solutions (Bryan, Manabe and Pacanowski, 1975): A h > 0.17 * ß* dx³ (2) from (1) and (2) we can scale A h as A h ~ A h0 (dx/dx 0 )**3 cos(φ)cos(φ 0 ) (3) where the subindex 0 marks the latitude, and viscosity of the largest grid size in the domain (dx 0 ). In practice: Obtain A h0 from (2) (i.e., for the largest grid size), and then obtain the rest using (3).

4. Minimum Viscosity Coeff. (visc2) vs. Latitude A h =A h ( φ,dx)

5. MODEL's TOTAL KINETIC ENERGY vs. TIME

6. ROMS MGSVA Gulf Stream, Antilles Curr., Loop Current & Labrador Curr.

7. Kuroshio, Oyashio, Liman, Tsuchiya & Tsugaru Currents

8. from MGSVA Malvinas-Brasil Confluence Area summer winter

9. TROPICAL PACIFIC CURRENTS AND SST

10. Tropical Instability Waves

11. Across-equator zonal velocity profiles (152 °W – Hawaii-Tahiti transect) From Johnson & Luther (1994) - current meter data ROMS

12. 150 m Surface Winter Flows off California

13. STRAIT OF GIBRALTAR Mean speed from ROMS Mean speed from obs (ADCP)

14. Guinea, Equatorial and Angola Currents MGVSA

15. TRANSPORT THROUGH DRAKE PASSAGE Malvinas Whitworth & Peterson (1985)(*)=134  13 Sv Various ACDP estimates from the Univ. of Southampton=94Sv-155Sv ROMS : 128 Sv

16. ANTARCTIC CIRCUMPOLAR CURRENT

17. (from L. Talley, SIO) Global Salinity Minimum Global ROMS

18. SEA LEVEL COMPARISON AT SAN FRANCISCO

19. CLIMATIC INDEXES FROM 56-y RUN: PDO and NI ÑO3.4 Corr=0.67; Coherence for 25y harmonic: 0.91 (10 ° phase) Corr=0.73; Coherence for 4y harmonic=0.78 (ampl=0.7 & phase =7 °)

20. Planned Applications of the Global ROMS Couple “GOMS” to an atmospheric model (ECPC fcsts) Use its output (climat & hincdast) as OBCs in regional models (a few latin american scientists are interested in this) Sea level (*)& climatic studies. Studies on water mass formation (NPIW and Ross Sea area) Future runs/planned improvements: Filter forcing with Killworth's matrix to obtain more realistic amplitudes (*) (e.g., Nino3.4 index). Include sea-ice. (*) underway