1. Representing the Effects of Eddy Stress in the Arctic Z. Wang G
Representing the Effects of Eddy Stress in the Arctic Z. Wang G. Holloway Y. Lu D. Wright Fisheries and Oceans Canada

2. Outline Model description Neptune --- Summary What is Neptune?
impacts on Arctic circulations
flows in the Canadian Arctic Archipelago
transports and properties in Fram Strait
Summary

3. Neptune - “topostress”
Model Description
Uses the NEMO ocean module (z-level, C-grid) and LIM2 ice module (2 ice layers, 1 snow layer)
Nominally 1-deg resolution; tri-polar grid with finest resolution in Arctic/CAA; enhanced resolution in tropics
Forcing: A daily climatology derived from ECWMF reanalysis; monthly river runoff
Bulk formulae
Neptune - “topostress”
Representing effects of eddy-topography interactions
Barotropic flow relaxed to a mean current in the direction of topographic Rossby wave propagation

4. Neptune velocity in the Arctic
The barotropic velocity
field that we relax towards

5. Impact of Neptune: Arctic Circulation at 51 m depth

6. Impact of Neptune: Arctic Circulation at 226 m depth

7. Impact of Neptune: Arctic Circulation at 531 m depth

8. Impact of Neptune: Arctic Circulation at 984 m depth
Arctic 984m

9. Canadian Arctic Archipelago Circulation
Having the difference plot appear on top of the Neptune plot would help to see what has changed.

10. Model assessment based on topostrophy, τ
Current meter locations in the Arctic
Friction: skill=0.37
Neptune: skill=0.79

11. Neptune impact on flow through Fram Strait
The result without Neptune
The change due to Neptune

12. Temperature at 79N, modelled and observed
Average of the monthly means measured by a
moored array in
AWI

13. Fluxes through Fram Strait
Friction
Neptune
OBS
Volume transport|(Sv)
North
1.27
2.38 10
Schauer
South
3.90
4.47 12
Ice volume
(km3/year)
2838
2649
(Aagaard and Carmack 1989)
Heat
(TW) 17 27
24-36
Schaurer(ASOF book)
Freshwater-liquid
(mSv) 45 56
63.1 Lique(2009)

14. Ice thickness in March Neptune - Friction Friction
Suggest showing Friction and Neptune first and then have Neptune-Friction appear on top of the Neptune result. Similar to slide 9.

15. Summary
Neptune ---
brings large scale Arctic circulation closer to observed
produces the observed reversed flows in the CAA
improves the heat and freshwater transports
reduces the width of the ice tongue in the Fram Strait