1. CLIVAR 11 th -12 th -13 th February 2009. A 44 years ocean circulation hindcast using a 3D model: steric effect in sea level variability M.I. Ferrer, M.G. Sotillo, E. Álvarez-Fanjul, D. Gomis, P. Oddo, J.M. Baldasano.

2. CLIVAR 11 th -12 th -13 th February 2009 Index  VANIMEDAT Project & Objectives  Oceanic Model: NEMO  Hindcast configuration  Validation  Conclusions

3. CLIVAR 11 th -12 th -13 th February 2009 Project & Objectives  VANIMEDAT project (funded by Ministerio de Educación y Ciencia) Sea level decadal and interdecadal variability in the Mediterranean Sea. oDirect determination of the steric component from a baroclinic model forced by HIPOCAS air-sea fluxes. oRun 44 years (1958-2001) NEMO model using HIPOCAS atmospheric forcing.  Data base used to study variability in the Mediterranean Sea and Iberian Atlantic Waters

4. CLIVAR 11 th -12 th -13 th February 2009 Model: NEMO  NEMO (Nucleus for European Modelling of the Ocean) is a state- of-the-art modelling framework for oceanographic research, operational oceanography seasonal forecast and climate studies. oOcean dynamics: NEMO-OPA  Evolution and reliability of NEMO are organised by a European Consortium between oCNRS (Centre National de la recherque scientifique) oMercator-Ocean oUKMO (Met Office) oNERC (Natural Environment Research Council)  Website: www.nemo-ocean.eu

5. CLIVAR 11 th -12 th -13 th February 2009 Hindcast configuration  Model domain  Horizontal res. 1/8º  Vertical res. 72 levels  14ºW-36.25ºE  30.25ºN-46ºN  Initial conditions: T/S ORCA model (resolution 1/4º) Global ocean-ice model for a long simulation (1958-2004) Initial salinity Initial temperature Bathymetry (m) Initial salinity Initial temperature

6. CLIVAR 11 th -12 th -13 th February 2009 Hindcast configuration  Forcing: oAtmospheric forcing with bulk formula: HIPOCAS data base  time resolution: hourly  spatial resolution ~0.5º oRelaxation to surface ORCA salinity  time resolution: monthly files  spatial resolution 1/4º oAtlantic damping to salinity and temperature (ORCA) in a buffer zone

7. CLIVAR 11 th -12 th -13 th February 2009 Hindcast configuration  Forcing: oAtmospheric forcing with bulk formula: HIPOCAS data base  time resolution: hourly  spatial resolution ~0.5º oRelaxation to surface ORCA salinity  time resolution: monthly files  spatial resolution 1/4º oAtlantic damping to salinity and temperature (ORCA) in a buffer zone

8. CLIVAR 11 th -12 th -13 th February 2009 Hindcast configuration  Initial configuration (bathymetry, rivers) from INGV (Instituto Nazionale di Geofisica e Vulcanologia, Bologna)  Bulk formulation from INGV  Linear free surface filtered formulation  MPI parallel mode  The 44-years hindcast is running at Marenostrum supercomputer located in Barcelona Supercomputing Center (BSC)

9. CLIVAR 11 th -12 th -13 th February 2009 Validation  Validation first period January 1991 to November 2001 oTime series of surface salinity, temperature. oRMSE  Data sets: oAVHRR SST oMedatlas Climatology oORCA model

10. CLIVAR 11 th -12 th -13 th February 2009 Surface Temperature Monthly Mean Satellite (green) NEMO (black) ORCA (blue)

11. CLIVAR 11 th -12 th -13 th February 2009 Surface Temperature differences NEMO-Sat (black) ORCA-Sat (blue)

12. CLIVAR 11 th -12 th -13 th February 2009 Surface Salinity Monthly Mean Medatlas (red) NEMO (black) ORCA (blue)

13. CLIVAR 11 th -12 th -13 th February 2009 RMSE Medatlas Salinity

14. CLIVAR 11 th -12 th -13 th February 2009 Conclusions  An ocean reanalysis tool based on a 3D baroclinic model forced by hourly HIPOCAS data has been developed.  Extensive validation for the period 1991-2001 show good agreement with data.  The generated data will be useful to study ocean climate variability, upgrading the HIPOCAS database.  The model application is a powerful tool to generate future scenarios.