1. NEMO Developments and application at the Bedford Institute of Oceanography, Canada F. Dupont, Y. Lu, Z. Wang, D. Wright Nemo user meeting 2009Dalhousie-DFO

2. Code updates NEMO2.3 Spectral nudging enabled in NEMO. AGRIF enabled with ice included (LIM2). Neptune Effect. JGR, Holloway and Wang, accepted. Smagorinsky type eddy diffusion parametrization. OBCs fully enabled. No computed phase velocity used, advective velocity instead for radiation. Best would be to include first-baroclinic phase speed. OBC volume conservation for multi-processors: missing mask for active nodes, added double double precision summation. OBC tides, including astronomical tides. Dalhousie-DFO Nemo user meeting 2009

3. Spectral nudging No-spectral nudging

4. AGRIF test with ¼ degree NA with 1/12 degree embedded. This test run has been run for only 5 years and the statistics only excludes the first 12 month Remaining issues: correcting at each time-step E-P fields too difficult. Annual volume correction done instead. Nemo developer meeting 2009

5. AGRIF NO-AGRIF

6. Increasing Resolution Regionally: Example of SST and Sea Ice Prediction Based on Local Grid Refinement Results from a 1 degree global model with a NA zoom to ¼ degree Region with ¼ degree resolution Results from enhanced resolution region illustrating new ability to use AGRIF in ice infested regions White indicates ice cover

7. Application to the global circulation using ORCA1 (UK setup)

8. RMS of InterAnnual Sea-Level 1993-2004 Obs 1º model

9. Tropical Pacific Variability Also reproduces changes associated with MJO

10. Forcing sensitivity – Interannual Variability Wind Heat

11. Benefit of Increased Resolution: Sub-surface Flow from ¼° model

12. 1º NEMO Multi-Decade Simulation using CORE Sea-ice concentration 1990-1996 Model (left) Obs. (right)

13. September integrated ice area

14. Fram Strait transport

15. Regional variation in ice area Wind important in all regions for interannual variations Heat forcing mostly important in REG1

16. March Sea-ice velocity for the last year of a 10 year run 1º model with OMIP forcing

17. March Sea-ice velocity for the last year of a 6 year run 1/4º model with OMIP forcing Although ocean currents are more realistic in the 1/4° simulation, the sea ice velocities are apparently still substantially overestimated.

18. Code Questions AGRIF + NEMO3: FLD issue -> has 'conv' been updated for dealing with FORTRAN structure type? If not, this sounds like a prirority. BBL issues? Restartibility issue? AGRIF + time-splitting.This would require that the barotropic variables (ssh,ua_e) are interpolated in time at each barotropic time-step and force the child domain at the boundary. Useful for tidal applications. Dalhousie-DFO Nemo developer meeting 2009

19. NEMO BBL Problem Model: NEMO2.3 ORCA1, 46 levels CORE “normal-year” forcing Test runs: Run 1: BBL diffusion set to 2000 m2/s Run 2: BBL diffusion set to 20000 m2/s

20. NEMO BBL Problem Run with small BBL diffusion Run with large BBL diffusion