- CONSERV:
CONSERV performs a global modification of the coupling field.
This analysis requires the source and target grid mesh areas to be
present in the areas.nc) file or transferred to the coupler with oasis_write_area (see section
2.2.4). For a correct CONSERV operation,
overlapping grid cells on the source grid or on the target grid
must be masked. In the namcouple, CONSERV requires
one input line with one argument and one optional argument:
# CONSERV operation
$CMETH $CONSOPT
where:
- $CMETH is the method desired with the following choices
- with $CMETH = GLOBAL, the field is integrated on both
source and target grids, without considering values of masked
points, and the residual (target - source) is uniformly
distributed on the target grid; this option ensures global
conservation of the field
- with $CMETH = GLBPOS, the same operation is performed
except that the residual is distributed proportionally to the
value of the original field; this option ensures the global
conservation of the field and does not change the sign of the
field
- with $CMETH = BASBAL, the operation is analogous to
GLOBAL except that the non masked surface of the source
and the target grids are taken into account in the calculation
of the residual; this option does not ensure global conservation
of the field but ensures that the energy received is
proportional to the non masked surface of the target grid
- with $CMETH = BASPOS, the non masked surface of the
source and the target grids are taken into account and the
residual is distributed proportionally to the value of the
original field; therefore, this option does not ensure global
conservation of the field but ensures that the energy received
is proportional to the non masked surface of the target grid and
it does not change the sign of the field.
- $CONSOPT is an optional argument specifying the
algorithm. $CONSOPT can be bfb or opt.
- The bfb option enforces a bit-for-bit transformation regardless
of the component grid decomposition or number of processes. It is currently the default setting.
With bfb, the entire field is gathered from the different component processes to the master process that performs the global integration and then
broadcasts the resulting sum to all component processes. Compared to opt, bfb is clearly more expensive with respect to
MPI communications and memory requirement.
- The opt option
carries out the global conservation with an optimal algorithm using less
memory and a faster approach. With opt, a local sum is performed on each process that then sends its local sum to all other processes; all processes can then compute the global sum of all local sums. This is more efficient than the bfb algorithm but does not ensure bit-for-bit reproducibility when the grid decomposition or number of processes of the component are changed.
- SUBGRID: UNUSED
- BLASNEW:
BLASNEW performs a scalar multiply or scalar add to any
destination field. This is the equivalent of BLASOLD on the
destination side. The prior feature that supported linear
combinations of the current coupling field with any other fields
after the interpolation has been deprecated.
This analysis requires the same input line(s) as BLASOLD.
- MASKP: UNUSED
- REVERSE: UNUSED
- CHECKOUT:
CHECKOUT calculates the global minimum, the maximum and the
sum of the target field values (not weighted by the grid cell area)
and prints them to the OASIS3-MCT debug file (for the master process
of the target component model only). These informations are found in
the debug file of the master process of the target model under the
attribute ``diags''. This operation does not
transform the field. CHECKOUT operation can significantly slow down the simulation.
It should not be used in production mode.
The generic input line is as for CHECKIN (see above).
- GLORED: UNUSED
