1. E. Golubeva, G.Platov, M.Krayneva, D.Yusupova elen@ommfao.sscc.ru Institute of Computational Mathematics and Mathematical Geophysics, SB RAS Novosibirsk, Russia

2. The main issue of the report - if we can simulate the propagation of Atlantic waters in the Arctic Ocean on the basis of a coarse resolution numerical model?

3. Coupled Ice-Ocean Model 3D Ocean Circulation Model of ICMMG based on z-level vertical coordinate approach (Kuzin1982, Golubeva at al.,1992, Golubeva,[2001], Golubeva and Platov,[2007]) Conservation laws for heat, salt and momentum with Boussinesq, hydrostatic and ‘rigid lid’ approximations Separation of the external and internal mode in momentum equations Barotropic momentum equations are expressed in term of stream function QUICKEST (Leonard,[1992]) is used in the latest model version for the T-S advection. Two versions of mixed layer parameterization: - Vertical adjustment based on the Richardson number - Vertical diffusion coefficient based on the stable solution of turbulent energy equation Ice model-CICE 3.0 (elastic-viscous-plastic) W.D.Hibler,1979, E.C.Hunke, J.K.Dukowicz,1997, G.A.Maykut 1971 C.M.Bitz, W.H.Lipscomb 1999,J.K.Dukowicz, J.R.Baumgardner 2000, W.H.Lipscomb, E.C.Hunke 2004 34-50км, and 14-19км 38 vertical levels

4. According to the investigations [J.H. Swift, K. Aagaard, L. Timokhov, and Ev.G. Nikiforov, 2004], based on the enhanced version of the 1948-1993 data EWG (Gore-Chernomyrdin environmental bilateral agreement, Environmental Working Group,1997), there were some warm and cold events in the Atlantic layer of the Arctic Ocean during this period PeriodHYPOTHESIS 1955- the end of 1950-s Warm period The phase propagation of the warm anomaly of is consistent with a Fram Strait origin 1963 -1969Warm period enhanced horizontal heat advection and reduced vertical heat loss associated with increased upper-ocean stratification. 1974- the end of 1980-s Cold periodenhanced cooling of the Atlantic waters entering the Arctic Ocean via the Barents and Kara seas 1989-1993Warm period The phase propagation of the strong warm anomaly of the early 1990s is consistent with a Fram Strait origin

5. Model temperature at the depth 200 m

6. Dmitrenko, I, Polyakov IV, Kirillov S, Timokhov L, Frolov IE, Sokolov VT, Simmons HL, Ivanov VV, Walsh D. 2008. Towards A Warmer Arctic Ocean: Spreading Of The Early 21st Century Atlantic Water Warm Anomaly Along The Eurasian Basin Margins. Journal of Geophysical Research. 113:C05023 Update Beszczynska-Möller et al., 2012

7. http://www.cpc.ncep.noaa.gov/products/precip/CWlink/pna/JFM_season_ nao_index.shtml

8. Model temperature time series

9. NAO index Model temperature In the Norwegian Sea

10. Numerical test: homogeneous ocean, idealized topography, the source - wind stress 1948-2012 Empirical Orthogonal Function (EOF) analysis

12. Evolution of the AWI spatial distribution over the three time periods From Pascaline Bourgain and Jean Claude Gascard GEOPHYSICAL RESEARCH LETTERS, VOL. 39, L05603, doi:10.1029/2012GL051045, 2012 Numerical run. Tracer distribution at the depth of 300m

13. Velocity at the depth of 400m 1970 1990 2007

14. Thank you! The main issue of the report - if we can simulate the propagation of Atlantic waters in the Arctic Ocean on the basis of a coarse resolution numerical model? If YES What is the resolution necessary to simulate this process? What parameterizations of unresolved processes are needed? If NO