1. Ocean Instabilities Captured By Breeding On A Global Ocean Model Matthew Hoffman, Eugenia Kalnay, James Carton, and Shu-Chih Yang

2. Quick Overview of Breeding Developed by Toth and Kalnay (1993, 1997) to estimate the shape of growing errors in a non-linear atmospheric model The parameters can be tuned to isolate instabilities of different time scales Yang et al. (2005) used breeding on a coupled GCM to identify slow growing ENSO modes

3. Our Model GFDL Modular Ocean Model (MOM) Driven by monthly averaged winds from 1950-1995 (same data set as used by Carton et al. in a 2000 reanalysis) Stretched grid in vertical and in latitude with highest resolution at the equator and in upper ocean

4. The Breeding Process A small, random perturbation is added to the initial state of the system Both the perturbed and unperturbed (control) conditions are integrated forward in time The control forecast is subtracted from the perturbed forecast, yielding the bred vector The bred vector is rescaled to it’s initial size and added to the control forecast as a new perturbation

5. 10-Day Bred Vectors

6. Pacific TIWs at 3.5°N

7. 30-Day Bred Vector 10-Day Bred Vector 30-Day Breeding vs. 10-Day Breeding

8. 30-Day Bred Vector 10-Day Bred Vector

9. Bred Vector Kinetic Energy Advection of KE Baroclinic energy conversion Barotropic energy conversion

10. Baroclinic Conversion Term ( )

11. Vertically and Monthly Averaged Baroclinic Conversion

12. Vertically and Monthly Averaged Barotropic Conversion

13. Baroclinic at 3.375°N Barotropic at 0.65°N Vertical Profiles of Monthly Averaged Energy Terms

14. Breeding can isolate instabilities of different time scales in a full ocean model. The bred vector energy equations show location, shape, and sign of energy conversion. This has been shown to work in the Atlantic and Indian Ocean as well. We plan on performing a more complete analysis of mid-latitude instabilities. Conclusions and Future Work

15. END

16. Initial Bred Vector

21. Tropical Instability Waves 10-day breeding time From January 1988 to December 1989 Equatorial Cold Tongue Background SST is shaded Bred Vectors are shown in contour