Assumption initial conditions are on z-levels when ln_sco = .true.

[jamesharle]

The initial conditions for runs ln_sco = .true. are assumed to be on z-levels based on gdept_1d. This is not immediately apparent from reading the manual.

A few options would be to either:

• modify code such that depth information is required in the initial condition file. This would allow an initial condition file, comprising a different number of levels and/or gird type, to be read in and interpolated onto gdept_0.
• remove the interpolation loop completely (bearing in mind the on-going simplification process) and impose that the initial conditions read in have to be on gdept_0, requiring a pre-processing step.

[jamesharle]

A fix I used a while back to get me going - could be tidied:

Index: dtatsd.F90
===================================================================
--- dtatsd.F90 (revision 5527)
+++ dtatsd.F90 (working copy)
@@ -22,6 +22,8 @@

USE lib_mpp ! MPP library
USE wrk_nemo ! Memory allocation
USE timing ! Timing

+ USE in_out_manager
+ USE iom

IMPLICIT NONE
PRIVATE

@@ -33,6 +35,9 @@

LOGICAL , PUBLIC

ln_tsd_tradmp !: internal damping toward input data flag

TYPE(FLD), ALLOCATABLE, DIMENSION(:)

sf_tsd ! structure of input SST (file informations, fields read)

+#if defined key_gen_IC
+ REAL(wp), ALLOCATABLE, DIMENSION(:,:,: ) :: gdept_init
+#endif

!! * Substitutions

# include "domzgr_substitute.h90"

@@ -147,6 +152,10 @@

!

INTEGER

ji, jj, jk, jl, jkk ! dummy loop indicies

INTEGER

ik, il0, il1, ii0, ii1, ij0, ij1 ! local integers

+#if defined key_gen_IC
+ INTEGER :: id, jpk_init, jpk_initm1 ! local integers
+ INTEGER , DIMENSION(4) :: ddims
+#endif

REAL(wp)

zl, zi

REAL(wp), POINTER, DIMENSION(:)

ztp, zsp ! 1D workspace !!----------------------------------------------------------------------

@@ -154,6 +163,18 @@

IF( nn_timing == 1 ) CALL timing_start('dta_tsd')
!
CALL fld_read( kt, 1, sf_tsd ) !== read T & S data at kt time step ==!

+
+#if defined key_gen_IC
+ CALL iom_open ( sf_tsd(jp_tem)%clname, sf_tsd(jp_tem)%num )
+ !! get dimensions
+ id = iom_varid( sf_tsd(jp_tem)%num, 'gdept', ddims )
+ jpk_init = ddims(3)
+ IF(lwp) WRITE(numout,*) 'Dimensions of ICs: ', ddims, jpk_init
+ ALLOCATE( gdept_init(jpi,jpj,jpk_init) )
+ CALL iom_get ( sf_tsd(jp_tem)%num, jpdom_data, 'gdept', gdept_init,1)
+ CALL iom_close( sf_tsd(jp_tem)%num ) ! Close the input file
+ jpk_initm1=jpk_init-1
+#endif

!
!
! !== ORCA_R2 configuration and T & S damping ==!

@@ -221,16 +242,30 @@

DO ji = 1, jpi

DO jk = 1, jpk ! determines the intepolated T-S profiles at each (i,j) points

zl = gdept_0(ji,jj,jk)

+#if defined key_gen_IC
+ IF( zl < gdept_init(ji,jj,1 ) ) THEN ! above the first level of data
+#else

IF( zl < gdept_1d(1 ) ) THEN ! above the first level of data

+#endif

ztp(jk) = ptsd(ji,jj,1 ,jp_tem)
zsp(jk) = ptsd(ji,jj,1 ,jp_sal)

+#if defined key_gen_IC
+ ELSEIF( zl > gdept_init(ji,jj,jpk_init) ) THEN ! below the last level of data
+#else

ELSEIF( zl > gdept_1d(jpk) ) THEN ! below the last level of data

+#endif

ztp(jk) = ptsd(ji,jj,jpkm1,jp_tem)
zsp(jk) = ptsd(ji,jj,jpkm1,jp_sal)

ELSE ! inbetween : vertical interpolation between jkk & jkk+1

+#if defined key_gen_IC
+ DO jkk = 1, jpk_initm1 ! when gdept(jkk) < zl < gdept(jkk+1)
+ IF( (zl-gdept_init(ji,jj,jkk)) * (zl-gdept_init(ji,jj,jkk+1)) <= 0._wp ) THEN
+ zi = ( zl - gdept_init(ji,jj,jkk) ) / (gdept_init(ji,jj,jkk+1)-gdept_init(ji,jj,jkk))
+#else

DO jkk = 1, jpkm1 ! when gdept(jkk) < zl < gdept(jkk+1)

IF( (zl-gdept_1d(jkk)) * (zl-gdept_1d(jkk+1)) <= 0._wp ) THEN

zi = ( zl - gdept_1d(jkk) ) / (gdept_1d(jkk+1)-gdept_1d(jkk))

+#endif

ztp(jk) = ptsd(ji,jj,jkk,jp_tem) + ( ptsd(ji,jj,jkk+1,jp_tem) - ptsd(ji,jj,jkk,jp_tem) ) * zi
zsp(jk) = ptsd(ji,jj,jkk,jp_sal) + ( ptsd(ji,jj,jkk+1,jp_sal) - ptsd(ji,jj,jkk,jp_sal) ) * zi

ENDIF

@@ -303,6 +338,9 @@

DEALLOCATE( sf_tsd(jp_sal)%fnow ) ! S arrays in the structure

IF( sf_tsd(jp_sal)%ln_tint ) DEALLOCATE( sf_tsd(jp_sal)%fdta )

DEALLOCATE( sf_tsd ) ! the structure itself

+#if defined key_gen_IC
+ DEALLOCATE( gdept_init )
+#endif

ENDIF
!
IF( nn_timing == 1 ) CALL timing_stop('dta_tsd')

[jamesharle]

I'm currently writing this code into my copy of the trunk. I was also thinking of removing this loop and putting it into domain_cfg TOOLS so the initial conditions are mapped onto the native vertical grid and written out when domain_cfg is used. That way they can be read in a runtime without the need for on-the-fly interpolation.

[mathiot]

James, one other solution could be to clarify the documentation and if you really want to to implement the capability and an action in the proposal for 2020 WP.

[jamesharle]

OK - I have an updated changeset for v4.0 that I've been using for ORCHESTRA, so won't be too much effort to add. I'll look over the documentation and discuss with Andrew.