1. The Inferred 3D velocity field Nelson Hogg (WHOI) The Inferred 3D velocity field Nelson Hogg (WHOI) Nelson Hogg: Missing PN Ranks with altimetry in terms of innovation and global reach Nelson Hogg: Missing PN Ranks with altimetry in terms of innovation and global reach

2. Themes Global coverage Influence of bottom topography Zonality of mid-depth flows Presence of annual signal at mid-depths Numerical models do reproduce some of these features

3. Surface: Mean Meridional Velocity Niiler and Maximenko (personal communication) Nelson Hogg: Change in sign of ekman @ equator Nelson Hogg: Change in sign of ekman @ equator

4. Surface: Mean Zonal Component Niiler and Maximenko (personal communication) Nelson Hogg: Banding in tropics wbcs Nelson Hogg: Banding in tropics wbcs

5. Surface: Eddy Kinetic Energy Niiler and Maximenko (personal communication) Stammer (persnonal communication) Satellite Surface Drifters

6. Kuroshio Extension: RMS eddy velocities from drifters and altimeters, and their ratio Niiler et al, 2002: (in press) Drifter RMS Altimeter RMS Drifter / Altimeter Coriolis Pressure Centrifugal Coriolis Pressure Centrifugal

7. Niiler et al, 2002: (in press) Shatsky Rise Emperor Seamounts Izu Ridge Mean Surface Velocity: Kuroshio Extension

8. North Atlantic: Mean Surface Circulation Fratantoni, 2001, JGR 106(10) Nelson Hogg: New england seamounts recirculations NAC and CGFZ Nelson Hogg: New england seamounts recirculations NAC and CGFZ

9. EKE Difference: Drifter – Altimeter Fratantoni, 2001, JGR 106(10)

10. North Atlantic: Mean surface velocity Niiler and Maximenko, pers. comm. Nelson Hogg: New England Seamounts Azores C NAC & CGFZ Reykianes Ridge Lab Sea and offshore recirc Nelson Hogg: New England Seamounts Azores C NAC & CGFZ Reykianes Ridge Lab Sea and offshore recirc

11. “Upper level” Streamlines Bower et al, 2002: Nature Lavender et al, 2000: Nature 700m    Nelson Hogg: See posters Nelson Hogg: See posters

12. LSW Streamlines Bower et al, 2002: Nature 1500m – 1750m Nelson Hogg: CGFZ Split at eastern b. Reyk. Ridge Nelson Hogg: CGFZ Split at eastern b. Reyk. Ridge

13. Influence of Mid-Atlantic Ridge on Rafos trajectories Bower et al, 2002, Nature

14. AAIW: South Atlantic Boebel et al, 1999, GRL 26 Nelson Hogg: Color scheme Eastward @ 20S Nelson Hogg: Color scheme Eastward @ 20S

15. IW (1000m) trajectories: North Pacific Steve Riser, pers. Comm. Nelson Hogg: Zonal trajectories Rounder streamlines Nelson Hogg: Zonal trajectories Rounder streamlines

16. AAIW displacements: South Pacific Davis, 1998, JGR 103

17. AAIW smoothed: South Pacific Davis, 1998, JGR 103

18. AAIW streamlines: South Pacific Davis, 1998, JGR 103

19. NADW: Brazil Basin (DBE) RAFOS Displacements CLIPPER simulation Hogg and Owens, 1999: DSRII Treguier et al, 2002: JPO

20. Vanicek and Siedler, 2002:JPO MAR influence? Possible Explanations ● Fracture Zones: Pedlosky (JPO,31) ● Variable mixing along MAR ● Wind forced: Nakano and Suginohara (JPO, 32)

21. Wind forced mid-depth zonal flows South Atlantic Clipper 1/6 degree Treguier et al, 2002: JPO Pacific COCO 1 degree Nakano and Suginahara, 2002: JPO Nelson Hogg: See posters Nelson Hogg: See posters

22. Annual signal in South Pacific Davis, 1998: JGR

23. Annual signal in Brazil Basin: Least squares fit @ 2500m RMS residual U V Hogg, in prep. U V

24. Annual signal in Brazil Basin: Phase Hogg, in prep.

25. Annual signal in Brazil Basin: Amplitude Hogg, in prep.

26. Annual Signal from Clipper: Zonal Velocity Thierry and Teguier, pers. Comm. Amplitude (cm/s)Phase (months)

27. Beta dispersion Hogg, in prep.

28. Application to inverse calculations Pacifiic: 32S Wijffels et al, 2001: JPO

29. Total: 1784 floats, 4300 float years

30. Nelson Hogg: 3650 = 1 float continuous for 10 yr Nelson Hogg: 3650 = 1 float continuous for 10 yr

31. Summary ● Float/drifter program has been a remarkable success and should be considered one of WOCE's crown jewels ● Much of the information is only semi- quantitative at best: more drifters of longer duration needed ● Use in constraining inverse models still in infancy: should be encouraged ● Float/drifter program has been a remarkable success and should be considered one of WOCE's crown jewels ● Much of the information is only semi- quantitative at best: more drifters of longer duration needed ● Use in constraining inverse models still in infancy: should be encouraged Nelson Hogg: Davis poster Nelson Hogg: Davis poster