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Re: CFC Analysis



Dear Dr. Dutay,

Thank you very much for your e-mail on the analysis plan.
We announce the information of our model briefly.

- - grid type (B,C..)

  Arakawa staggered B grid (Bryan, 1969)

- - Horizontal resolution

  4 x 4 degrees for longitude and latitude.

- - surface boundary conditions (T,S restoring, bulk formula (what kind))

  The model surface temperature and salinity are restored to reference 
  temperature and salinity (Levitus (1982) annual averaged 
  climatologies) except in the North Atlantic where the reference 
  temperature is set to be 4K cooler than the annual condition 
  at 60N and decreases linearly from 50N to 60N.

- - subgrid scale mixing (Horizontal, Isopycnal, Gent & Mc Williams..)
- -                       viscosity (ndlr for the dynamics)
- - and the value of all the coefficients of these prametrization

  Viscosity (harmonic operator)
    Horizontal (8.0E9 cm2/sec, spatially constant)
    Vertical   (0.15  cm2/sec, spatially constant)

  Diffusion (harmonic operator)
    Horizontal (8.0E6 cm2/sec, spatially constant)
    Vertical   (0.3   cm2/sec, spatially constant)

- - scheme for advection (centered, upstram..)

  We use the weighted upstream scheme which is defined as follows:
    C = aC(upstream) + bC(downstream)
      a = 0.85, b = 0.15 for horizontal advection,
      a = 0.97, b = 0.03 for vertical advection,
  where C is a tracer concentration.

- - mixed layer parametrization (if any), convective adjustment, 
- - TKE closure

  No mixed layer parameterization is included.
  Convective adjustment has been done for statically unstable cells.

- -ice model (what kind,..)

  No ice model is included.

- -time steps (dynamics and tracers)

  We use an offline model.
    36 hours for dynamics
    4 days for tracers

- -equation of state used to compute density (ex: Unesco 1983)

  UNESCO (1981).  
  Tenth report of the joint panel on oceanographic tables and 
  standards.  UNESCO Technical Papers in Marine Sci. No. 36,
  UNESCO Paris.

You could find detailed descriptions of our model in the following
paper:
  Yamanaka,Y. and E. Tajika (1996)
  The role of the vertical fluxes of particulate organic matter and 
  calcite in the oceanic carbon cycle: Studies using an ocean 
  biogeochemical general circulation model, 
  Global Biogeochem. Cycles, 10, 361-382

If you have any questions, please don't hesitate to contact me. 

Sincerely yours,

  Akio
================================================================================
Akio ISHIDA                           Institute for Global Change Research
                                Frontier Research System for Global Change
  SEAVANS North Bldg. 7F, 1-2-1, Shibaura Minato-ku, Tokyo 105-6791, Japan
  E-mail: ishidaa@frontier.esto.or.jp
  Tel: 81-3-5765-7100, Fax: 81-3-5765-7103
================================================================================