1. TOPAZ the Arctic TEP and the Arctic GOOS L. Bertino, G. Evensen, K.A. Lisæter, I. Keghouche Arctic GOOS opening, Bergen, 12 th Sept. 2006

2. Analysis 1 st Sept. 2006 Google Earth

3. TOPAZ System Description Model components Assimilation method Upgrades

4. Motivation  Objective:  Provide short-term forecasts of physical and biogeochemical parameters targeted to users needs (primarily the offshore oil and gas industry)  Strategy  Focus on advanced data assimilation techniques  Gradual increase of resolution  Nesting on regions of higher interest  Support  TOPAZ is the Arctic component of MERSEA IP  ESA, Industry, private donation (Frank Mohn AS, Bergen)

5. The TOPAZ model system  TOPAZ: Atlantic and Arctic  18-35 km resolution  22 vertical layers  Assimilates  SLA (4 satellite altimeters),  SST (from AVHRR),  ice concentrations (SSM/I)  Run weekly, ECMWF forcing  Provides nesting conditions to high-res. models

6. Ice concentration data  Passive MW (NSIDC)  Real-time data set (2-3 days delay)  NORSEX algorithm (Svendsen et al 1983)  37GHz, 19GHz  ~25 km resolution

7. Ice extent and ice volume Solid black line - ensemble mean Dashed black line - free run Grey - individual ensemble members

8. Barents Sea

9. TOPAZ2 (400x600x22) 20km resolution TOPAZ3 (800x880x22) 11km resolution

10. TOPAZ Upgrade Stronger W. Spitzberg Current TOPAZ3TOPAZ2

11. CERSAT - IFREMER

12. The Arctic TEP Thematic Portal Common Viewing Downloading Downscaling Validation Plan

14. Live Access Server

15. The MERSEA metrics

16.  Class1: 3D daily averages  Class2: Sections and moorings  Class3: derived quantities (fluxes)  Class4: validation to observations

17. Top 3 m layer

18. 100 m depths

19. Validation procedures against in-situ measurements and climatology Station at the North Pole TOPAZ profiles In-situ data from CORIOLIS (Argo, XBT, …)

20. Status / Plan  TOPAZ:  next upgrade (TOPAZ3) Apr. 2007  Ice drift data assimilation  Arctic TEP  Started during the TOP1 period (Oct. 2005)  Barents Sea model  Downscaling from TOPAZ.  Real-time since Sept. 2006.  MERSEA TOP2 period (Apr. – Sept. 07)  Contributions from all Mersea V2 systems  More validation metrics

21. Thank You

22. The ingredients  Models  HYCOM (U. Miami, USA)  Ice model  Biogeoch. model (AWI, D)  Observations  Altimetry, SST (CLS, F)  Sea Ice (NSIDC, USA)  Sea Ice drift (Cersat, F)  In-situ (CORIOLIS, F)  Data assimilation  Ensemble Kalman Filter [Evensen 1994, 2006]

23. Ensemble Kalman filtering a stochastic process ForecastAnalysis Observations 1.Initial uncertainty 2.Model uncertainty 3.Measurement uncertainty 1 2 3 Member1 Member2 …… Member99 Member100

24. Surface temperature update Assimilation update - Summer Ice concentration update Surface salinity update

25. Results from TOPAZ and nested models

26. Validation Salinity

27. Validation Temperature

28. Results from a nested model VOLUME TRANSPORTS How good are the boundary conditions ? BIC AW NCC

29. Norway-Bear Island Net transport AW: 1.5 Sv/year (1.7 Sv in winter and 1.3 Sv in Summer) [Ingvaldsen et al., 2004] Net transport NCC: 0.5 Sv/year [Blindheim, 1989] Net transport BIC: -???

30. Bear Island - Svalbard Recirculation within the Bear Island Trough is relatively stable at ~ 1.0 Sv [Ingvaldsen et al., 2002]

31. Svalbard – Franz Josef Land In => 0.4 Sv Out => 0.1 Sv [Loeng et al., 1997] (used Russian literature)

32. Frans Josef Land – Novaya Zemlja In = 0 to 0.3 Sv in Summer Out = 1.5 Sv (between 0.6 Sv in Summer and 2.6 Sv in Winter) [Schauer et al., 2002]

33. Kara Gate In = 0.1 Sv Out = 0.05 to 0.7 Sv [Loeng et al., 1997] (used Russian literature)

34. Planned upgrade - TOPAZ3

35. Expected improvements  Improved dynamics  Better resolution of shelf currents (esp. in the Nordic Seas)  Better fluxes in/out of the Arctic Ocean  More efficient assimilation of altimetry and hydrographic profiles. Norway Spitzberg Barents Sea opening TOPAZ2 TOPAZ3

36. Future Perspectives  Geographical extension  Indian ocean (under development)  Pacific Ocean / South China Sea (Nansen-Zhu, Beijing)  Exhaustive model validation  In collaboration with the MERSEA gang  Real-time assimilation of more observations  Temperature and salinity profiles (Argo program)  Ice thicknesses (CRYOSAT)  Sea surface salinity (SMOS / Aqua)  New geoid and Mean Dynamic Topography (GOCE)  Progresses in data assimilation  Biases, non-linearity, parameter estimation  Coupling to a global system  Mercator

37. The end

38. System Applications Nested systems in 1.North Sea (N. Winther/C. Hansen) 2.Gulf of Mexico (F. Counillon) 3.Barents Sea (I. Keghouche)

39. Illustr. I. Kerghouche