2. A data-model comparison study of the Arctic Ocean's response to atmospheric mode of variability Bruno Tremblay Robert Newton Peter Schlosser Lamont Doherty Earth Observatory of Columbia University Acknowledgment: NSF, A. Weaver – M Eby

3. Introduction Summer and winter changes in the thermocline Hypothesized that these changes may also be present on longer time scale Hunkins and Whiteheads tank experiments read that paper Tide gauge (PSMSL) data Tide gauge locations Do they vary together or not?

4. Introduction continued TG time serie + regime shift of the mid 70's; show how it is present in TG and SLP time series Local to the chukchi sea or arctic wide? Show how TG correlates with slp, vorticity... Is it an inverted barometer effect or a large- scale dynamic effect? Subtract the inverse barometer effect

5. Introduction continued Uvic-ESCM ocean model 1.8 x 3.6 x 19level Disclaimer, problem with mean climate Ice area and volume export from Uvic (validation) Liquid fresh water outflux, and how it correlated with slp, and vorticity Total fresh water content of Arctic Ocean, how it correlates with vorticity input and arctic regimes How Total FW content correlated with FW flux

6. Introduction continued Aagaard and Caarmaack: Ice export : 2790 km3/year Water export : 1160 km/year Meredith et al: water export might be much larger.

7. Introduction continued

8. Tank experiment

9. Tidal gauge station (PSMSL)

10. SSH – Inverse barometer effect Jan 1, 1949

11. Sea surface height anomaly (norm)

12. Sea surface height anomaly

13. TG data and Atm indices

14. March SIC and thicknes

15. Fram Ice Area Flux

16. Fram Ice Area Flux – NAO

17. Fram Ice Volume Flux

18. Fram Ice Volume Flux – NAO

19. Regime shift – mid 70's Hilmer and Jung

20. SLG – NAO

21. EOF1 – FM SLP 1977-1999

22. FW content -- SLP

23. FW content – NAO

24. FW flux – SLP

25. FW flux – FW content

26. Conclusions Ice export goes with NAO (recently) Water export goes with NAO as well Water export is not linked with FW content of Arctic FW content of arctic goes with SLP or vorticity presumably due to increase ice formation during lower pressure in arctic Expect a more complicated link between FW content and export when the FW export is more in line with real thing

27. Conclusions Longer term FW content changes are larger than seasonal changes They account for x km3/year compared with y km3 /year for ice export

28. Future work Experiment with the wind forcing to get the proper surface water export Dye river and other source of fresh water to break it into component