Contact: B. Wyman
Reviewers:
Change history: WebCVS Log for bgrid_sponge.f90
Eddy damping of prognostic fields at the top level of the model.
Damping is done using a 5-point Shapiro filter.
For temperature, tracers, and zonal wind the zonal mean is
removed before applying the filter. For meridional wind,
the entire field is damped. Coefficients are controlled
through namelist input.
bgrid_horiz_mod bgrid_masks_mod bgrid_prog_var_mod bgrid_change_grid_mod bgrid_halo_mod fms_mod mpp_domains_mod
use bgrid_sponge_mod [ ,only: sponge_init,
sponge_driver ]
sponge_init
Mandatory initialization routine for bgrid_sponge_mod.
Initializes sponge control parameters.
sponge_driver
Computes tendencies for sponge damping.
NOTES
* A namelist interface called bgrid_sponge_nml is read
from file input.nml.
call sponge_init ( Hgrid )
DESCRIPTION
This routine reads the bgrid_sponge_nml namelist and then defines
sponge control parameters (stored internally in sponge_control_type).
INPUT
Hgrid Data structure containing horizontal grid constants.
[horiz_grid_type]
call sponge_driver ( Hgrid, nplev, dt, dpde, Var, Var_dt )
DESCRIPTION
Updates the prognostic variable tendencies with sponge (eddy damping)
tendencies. The damping coefficients are controlled by namelist.
INPUT
nplev number of "pure" pressure levels at the top of the model
[integer]
dt adjustment time step [real]
dpde current pressure thickness of model layers
[real, dimension(Hgrid%ilb:,Hgrid%jlb:,:)]
Var prognostic variables at the end of the last dynamics time step
[prog_var_type]
INPUT/OUTPUT
Hgrid horizontal grid constants [horiz_grid_type]
Var_dt prognostic variable tendencies
accumulated since the variables were updated in Var
[prog_var_type]
NOTES
The eddy damping is applied to "current" fields that have
been updated with their time tendencies.
For example, temp(current) = Var % t + dt * Var_dt % t.
&bgrid_sponge_nml
num_sponge_levels The number of uppermost model levels where
the sponge damping is applied. Currently,
this cannot exceed one level.
[integer, default = 0]
sponge_coeff_wind Normalized [0,1] sponge damping coefficients
sponge_coeff_temp for the top model level.
sponge_coeff_tracer [real, default = 0.]
FATAL errors in bgrid_sponge_mod
initialization not called
Interface sponge_driver was called before calling sponge_init.
numlev > 1
This version applies the sponge at only one model level.
The namelist value cannot be set > 1.
None.
None.