Custom Query (986 matches)

The variable idefQCK in mod_ncparam.F was unallocated. This was giving a segmentation error in output.F line 147:

forrtl: severe (408): fort: (2): Subscript #1 of the array IDEFQCK has value 1 which is greater than the upper bound of -1

Image              PC                Routine            Line        Source
oceanG             000000010E8687B4  _output_                  147  output.f90
oceanG             000000010E7DE034  _main3d_                  215  main3d.f90
oceanG             000000010D8670FD  _ocean_control_mo         178  ocean_control.f90
oceanG             000000010D865261  _MAIN__                    86  master.f90
oceanG             000000010D864D16  Unknown               Unknown  Unknown

when input parameter NDEFQCK had a nonzero value during the creation of the QUICKSAVE output NetCDF file.

Also, fixed the inquiring of existing QUICKSAVE file during restart in def_quick.F. Need to add surface variables for momentum and tracers so they can be appended to an existing QUICKSAVE file. The surface tracer variables indices need to be stored in QCK(ng)%Vid(idsurT(itrc)) instead of QCK(ng)%Tid(itrc).

Many thanks to users at NOAA for bringing this to my attention.

It had come to my attention that some users set NADJ in ocean.in to a large number to trigger strong constraint in 4D-Var dual formulation alogorithms (W4DPSAS or W4DVAR). Well, this is not a good idea because the algorithms will become unstable.

In the dual formulation, we need to set NADJ to NTIMES for strong constraint or to an exact multiple of NTIMES for weak constraint. For example, in ocean.in we can have:

      NTIMES == 192
...
        NADJ == 48                              ! weak constraint
or
        NADJ == 192                             ! strong constraint

In the primal formulation (IS4DVAR), you can put any number for NADJ because it is over-written internally in read_phypar.F:

#if defined IS4DVAR
!
!  If strong constraint, write only final adjoint solution since only
!  we are estimating initial conditions.
!
        nADJ(ng)=ntimes(ng)
#endif

To avoid similar problems in the future, a safeguard is added in read_phypar.F for the dual formulation:

#if defined W4DPSAS || defined W4DVAR
!
!  If dual formulation and strong constraint, limit writing the adjoint
!  solution to the end of time-stepping.
!
        IF (nADJ(ng).gt.ntimes(ng)) THEN
          nADJ(ng)=ntimes(ng)
        END IF
#endif

This is a minor update to the 4D-Var algorithms:

• The routines load_ADtoTL_tile and load_TLtoAD_tile in ini_adjust.F were updated to include the multiplication by the land/sea masking before manipulating the adjoint and tangent linear solutions, respectively. This is done to suppress a leak from the land/sea boundaries into the interior solution when the horizontal convolutions are applied. This is needed for W4DPSAS with RPCG to give the same solutions as I4DVAR. Many thanks to Andy Moore for bringing this to my attention.

• Added the missing arguments to several routines called in normalization.F when the option GEOPOTENTIAL_HCONV is activated. The horizontal convolution of the error covariance along geopotential is experimental and not fully tested. Please avoid using this option for now until we advise its usage.

• Added logic in read_asspar.F to make sure that Lprecond is false in input script s4dvar.in for the dual formulation 4D-Var drivers (W4D-PSAS and W4D-Var) when the RBLanczos minimization (RPCG) is activated.