PUBLIC INTERFACE ~ PUBLIC ROUTINES ~ NAMELIST

Module ocean_shortwave_csiro_mod

Contact:  Russell Fiedler
Reviewers:  S.M. Griffies ,  Alexander Pletzer
Change History: WebCVS Log

OVERVIEW

This module returns thickness and density weighted temperature tendency [kg/m^3 * deg C *m/sec] from penetrative shortwave heating.

Compute thickness and density weighted tendency [deg C *m/sec *kg/m^3] of temperature associated with penetrative shortwave heating in the upper ocean. Generally penetration is taken as a function of monthly optical properties of the upper ocean, where optical properties are read in from a file of climatological data. This module ussumes a simple single exponential decay law. The e-folding depth may vary spatially and temporaly. This routine is commonly used by researchers at CSIRO Marine and Atmospheric Research in Australia. It has been optimized for vector peformance in June 2003 on the Australian NEC computer.

OTHER MODULES USED

          axis_utils_mod
       field_manager_mod
                 fms_mod
                 mpp_mod
time_interp_external_mod
       ocean_domains_mod
         ocean_types_mod

PUBLIC INTERFACE

ocean_shortwave_csiro_init:
sw_source_csiro:
sw_pen:

PUBLIC ROUTINES

  1. ocean_shortwave_csiro_init

    DESCRIPTION
    Initialization for the shortwave module


  2. sw_source_csiro

    DESCRIPTION
    Add short wave penetrative heating to T_prog(index_temp)%th_tendency. Note that the divergence of shortwave for the first level "div_sw(0)" is compensating for the effect of having the shortwave component already included in the total surface tracer flux "stf(i,j,temp)"


  3. sw_pen

    DESCRIPTION
    Absorbtion of shortwave radiation in the water assumes energy partitions represented by a single exponential: The exponentialsrepresents a parameterization of the attenuation coefficient for light between 300 um and 750 um in the following form: E(z) = E(0) * exp(z/efold)) with z < 0 the ocean depth The "efold" s the efolding depth of the long and short visable and ultra violet light. efold will vary between 30 m in oligotrophic waters and 4 m in coastal regions. If the thickness of the first ocean level "dzt(1)" is 50 meters, then shortwave penetration does not do much. However, for finer vertical resolution, such as dzt(1) = 10 meters commonly used in ocean climate models, the effect of shortwave heating can be significant. This can be particularly noticable in the summer hemisphere.


NAMELIST

&ocean_shortwave_csiro_nml

use_this_module=
Must be .true. to run with module. Default is false.
[logical]
read_depth
If .true. then read in e folding depth for radiation attenuation.
[logical]
sw_frac_top
The fraction of shortwave radiation that should be incorporated into the sw_source array at k=1. The generic treatment in MOM is to assume that shortwave radiation is already contained inside the T_prog(index_temp)%stf field. Hence, to avoid double counting, sw_frac(k=0)=sw_frac_top should=0.0. If one removes shortwave from stf, then set sw_frac_top=1.0.
[real]
zmax_pen
Maximum depth of penetration of shortwave radiation. Below this depth, shortwave penetration is exponentially small and so is ignored.
[real, units: meter]
depth_default
Default efolding depth = 20m.
[real, units: mg/m^3]
enforce_sw_frac
To ensure the shortwave fraction is monotonically decreasing with depth.
[logical]
sw_pen_fixed_depths
To compute penetration assuming fixed depths via Grd%zw(k) depths. This is strictly incorrect when have undulating free surface or generatlized vertical coordinates. This option is here for purposes of legacy, as this was done in MOM4.0 versions. The default is .false.
[logical]
debug_this_module
For debugging purposes.
[logical]

REFERENCES

  1. Jerlov (1968) Optical Oceanography Elsevier Press
  2. Morel and Antoine (1994) Heating rate in the upper ocean in relation to its bio-optical state Journal of Physical Oceanography vol 24 pages 1652-1664
  3. Paulson and Simpson (1977) Irradiance measurements in the upper ocean Journal of Physical Oceanography vol 7 pages 952-956
  4. Rosati and Miyakoda (1988) A General Circulation Model for Upper Ocean Simulation Journal of Physical Oceanography vol 18 pages 1601-1626.

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