Prsentation PowerPoint

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DRAKKAR PLANED ACTIVITIES 2007-2010
LEGI/LPO/LOCEAN
Improvement of model configurations ORCA025,
NATL12, NATL4-AGRIF Variability of the subpolar
Atlantic (ORCA025, NATL12, NATL4) Variability
of the Southern Ocean (ORCA025, PERIANT025, AGRIF)
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• Improvement of model configurations ORCA025,
  NATL12, NATL4-AGRIF
• 1 - Internal parameterisations
• Sensitivity to the vertical resolution (64
  levels?)
• Parameterisation of subgridscale at ¼ resolution
• Parameterisation of the vertical mixing (tidal
  mixing in the Indonesian throughflow)
• Values of several key sea-ice parameters
•  
• 2 - Improvement of atmospheric forcing
• space/time resolution of satellite winds,
• freshwater forcing,
• diurnal cycle in solar heat flux,
• accuracy of the atmospheric surface variables on
  recent periods (1990s and 2000s).

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• 3 - Eddy-resolving resolution
• Further develop NATL12 configuration local
  AGRIF refinement in NATL4 (AMEN)
• Validate in application studies on the role of
  the ocean mesoscale turbulence on water mass
  formation and cross-front transports.  
• 4 - Development of validation tools
• Development of statistical tools for a systematic
  quantitative model-observation comparisons with
  global observational databases (ENACT/ENSEMBLES
  AVISO).

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• Variability of the subpolar Atlantic
• (ORCA025, NATL12, NATL4)
• 1 - Mode water variability (AMEN) (Virginie
  Thierry, A.M. Treguier, collaboration with Eric
  de Boisséson and the OVIDE team)
• Identify the formation areas of subpolar mode
  water in the Eastern North Atlantic
• understand the mechanisms that set up its
  properties and its variability
• investigate the way mode water ventilates the
  interior of the gyres
• 2 - Characterisation of the boundary currents
  variability from high frequency to the decadal
  scale, and forcing mechanisms (A.M. Treguier, C.
  Guiavarch (post doc in 2007), a PhD student to
  start in 2007 at LPO, Gaelle Hervieux, PhD
  student at LEGI (2007), B. Barnier, T. Penduff,
  A. Wirth)
• Connexion between the Greenland-Iceland-Scotland
  overflow and the deep boundary current (2007)
• Interannual to decadal variability of the DWBC
  from the overflows to the subtropical gyre
  (2007-2008)
• High frequency variability of the boundary
  currents in the North Atlantic (2007)
• Wind-forced variability of the boundary current
  in the Irminger Sea (2007-2010)
• Variability modes and local processes
  (2007-2009)
• Exchanges between the boundary current and the
  interior (2008-2010)

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• 3 - Variability modes and local processes
  (2007-2009) Participants T. Penduff (LEGI), A.
  Lecointre (PhD starting in 2006, LEGI), A.M.
  Treguier (LPO), PhD student to start in 2008/2009
  (LPO), B. Barnier (LEGI).
• to characterize and study the transports of
  properties (especially mass, heat, salt) and
  their low-frequency fluctuations across the
  selected sections (48N, 36N, 24.5N, 52W,
  66W, WOCE A1E/AR7E Greeland-Ireland transect,
  OVIDE).
• to relate these 2D structure with basin-scale
  modes of variability, using observed, reanalyzed,
  and simulated data.
• 4 - Exchanges between the boundary current and
  the interior (2008-2010)
• Participants A.M. Treguier, T. Penduff, B.
  Barnier, J. Le Sommer, G. Madec, PhD student at
  LPO. Collaboration with the OVIDE team and Bruno
  Blanke.
• mass exchanges between the boundary current, the
  overflows, and the interior of the gyres
• water mass formation and transformation, by
  atmospheric forcing and mixing processes on the
  basin scale (including the boundary current).

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• Variability of the Southern Ocean
• (ORCA025, PERIANT025, AGRIF)
• 1 - Dynamics and variability of the Antarctic
  Circumpolar Current
• - Role of eddies in the density balance of the
  ACC
• Participants A.M. Treguier at LPO. Cooperation
  with S. Rintoul from CSIRO and M. England from
  UNSW in Australia.
•  
• - Role of eddies in the momentum balance of the
  ACC
• Participants J. Le Sommer at LEGI, A.M. Treguier
  at LPO and B. Barnier at LEGI. Ongoing discussion
  with C. Wilson at University of Liverpool.
• Is the geographical distribution of eddy
  vorticity forcing in the model simulations
  consistent with direct observations?
• What is the vertical structure of the eddy
  vorticity forcing?
• How is the eddy vorticity forcing related to
  topographic steering?

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• 2 - Life-cycle of Antarctic Bottom Water
•  
• - Role of katabatic winds and polynia on the
  production of AABW (MAR). Participants Pierre
  Mathiot (PhD student at LEGI), with contributions
  from B. Barnier, J. Le Sommer and J. M. Molines
  at LEGI, H. Gallée LGGE, A. M. Treguier at LPO.
  Cooperation with S. Rintoul and M. England from
  CSIRO in Australia. Ongoing discussion with A. de
  Montety et H. Goose for a possible cooperation
  with UC Louvain la Neuve.
• What is the impact of the katabatic winds on the
  local ocean circulation and sea-ice cover?
• What is the contribution of Antarcticas Coastal
  polynyas to the formation of Antarctic Bottom
  Water (AABW), a major component of the world
  ocean meridional circulation?

• 3 - Life-cycle of Mode Waters (SAMW and AAIW)
•  
• - Semi-annual variability of Intermediate waters.
  Participants  J. Le Sommer (LEGI), collaboration
  M. England (UNSW)
•  
• Does the SAO force the variability of water mass
  properties observed by Sun and Watts, 2002?
• Does the modulation of properties correspond to
  a variability of formation rates?
• Is the oceanic response dependent on the
  mechanical forcing (Ekman/subduction) or rather
  the thermodynamic forcing (heat and freshwater
  fluxes)?

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4 - Variability of cross frontal exchanges.
Participants A.M. Treguier, J. Le Sommer and G.
Madec, collaborations with M. England, S.
Rintoul, S. Speich and M. Arhan. One post-doc or
PhD student sought for 2008. GOODHOPE project.