drivers/nemo_concepts: add 'debug_ice' calls throughout 'ice_step'

In 97370d7 (Update testing, in particular for diagnostics and
decompositions (CICE-Consortium#602), 2021-05-26), the 'debug_model' namelist flag was
added and calls to 'debug_ice' were added throughout the standalone
model's 'ice_step'. This is useful for debugging model runs (in the
scientific sense) since this subroutine prints the complete ice state,
so calling it several times per time step can help diagnose where things
go wrong.

Do the same in the 'nemo_concepts' driver.

cicecore/drivers/direct/nemo_concepts/CICE_RunMod.F90

@@ -135,7 +135,7 @@ subroutine ice_step
 
       use ice_boundary, only: ice_HaloUpdate
       use ice_calendar, only: dt, dt_dyn, ndtd, diagfreq, write_restart, istep
-      use ice_diagnostics, only: init_mass_diags, runtime_diags
+      use ice_diagnostics, only: init_mass_diags, runtime_diags, debug_model, debug_model_iblk, debug_ice
       use ice_diagnostics_bgc, only: hbrine_diags, zsal_diags, bgc_diags
       use ice_domain, only: halo_info, nblocks
       use ice_domain_size, only: nslyr
@@ -197,6 +197,8 @@ subroutine ice_step
         call da_state_update
 #endif
 
+        if (debug_model) call debug_ice(debug_model_iblk, 'beginning time step')
+
       !-----------------------------------------------------------------
       ! restoring on grid boundaries
       !-----------------------------------------------------------------
@@ -210,6 +212,8 @@ subroutine ice_step
          if (istep == 1 .and. runtype == 'initial' .and. .not. restart) &
             call init_shortwave
 
+            if (debug_model) call debug_ice(debug_model_iblk, 'post re-init_shortwave')
+
       !-----------------------------------------------------------------
       ! initialize diagnostics and save initial state values
       !-----------------------------------------------------------------
@@ -234,14 +238,19 @@ subroutine ice_step
 
             if (calc_Tsfc .and. ktherm >= 0) call prep_radiation (iblk)
 
+            if (debug_model) call debug_ice(iblk, 'post prep_radiation')
+
       !-----------------------------------------------------------------
       ! thermodynamics and biogeochemistry
       !-----------------------------------------------------------------
 
             call step_therm1     (dt, iblk) ! vertical thermodynamics
+            if (debug_model) call debug_ice(iblk, 'post step_therm1')
+
             if (ktherm >= 0) then
                call biogeochemistry (dt, iblk) ! biogeochemistry
                call step_therm2     (dt, iblk) ! ice thickness distribution thermo
+               if (debug_model) call debug_ice(iblk, 'post step_therm2')
             endif
 
          enddo ! iblk
@@ -266,20 +275,24 @@ subroutine ice_step
 
             ! momentum, stress, transport
             call step_dyn_horiz (dt_dyn)
+            if (debug_model) call debug_ice(debug_model_iblk, 'post step_dyn_horiz')
 
             ! ridging
             !$OMP PARALLEL DO PRIVATE(iblk)
             do iblk = 1, nblocks
                call step_dyn_ridge (dt_dyn, ndtd, iblk)
             enddo
             !$OMP END PARALLEL DO
+            if (debug_model) call debug_ice(debug_model_iblk, 'post step_dyn_ridge')
 
             ! clean up, update tendency diagnostics
             offset = c0
             call update_state (dt_dyn, daidtd, dvidtd, dagedtd, offset)
 
          enddo
 
+         if (debug_model) call debug_ice(debug_model_iblk, 'post dynamics')
+
       !-----------------------------------------------------------------
       ! albedo, shortwave radiation
       !-----------------------------------------------------------------
@@ -291,12 +304,14 @@ subroutine ice_step
          do iblk = 1, nblocks
 
             if (ktherm >= 0) call step_radiation (dt, iblk)
+            if (debug_model) call debug_ice(iblk, 'post step_radiation')
 
       !-----------------------------------------------------------------
       ! get ready for coupling and the next time step
       !-----------------------------------------------------------------
 
             call coupling_prep (iblk)
+            if (debug_model) call debug_ice(iblk, 'post coupling_prep')
 
             ! compute components of diagnostic wind
             call diagnostic_wind_components(iblk)