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#2729 (Restartability failure of model configurations with embedded sea ice) – NEMO

Opened 3 years ago

Closed 3 years ago

#2729 closed Bug (fixed)

Restartability failure of model configurations with embedded sea ice

Reported by: smueller Owned by: smueller
Priority: low Milestone:
Component: SI3 Version: v4.0.*
Severity: minor Keywords: sea-ice, VVL
Cc:

Description

Context

A restartability test of a modified ORCA2_ICE_PISCES configuration with embedded instead of levitating sea-ice (ln_ice_embd = .true.) fails.

Analysis

The differences between corresponding restarted and non-restarted model runs appear to stem from the resetting of e3t_n and e3t_b values to e3t_0 values in grid cells where tmask is zero (source:/NEMO/releases/r4.0/r4.0-HEAD/src/OCE/DOM/domvvl.F90#L823) during model restarts of configurations without linear free surface (ln_linssh = .false.). During the initialisation of model configurations with ln_ice_embd = .true. and ln_linssh = .false., however, the update of the vertical scale factors due to the presence of sea ice and snow (source:/NEMO/releases/r4.0/r4.0-HEAD/src/ICE/iceistate.F90#L419) includes adjustments in grid cells where tmask is zero.

Fix

The adjustment of the vertical scale factors in grid cells where tmask is zero in subroutine ice_istate of module iceistate seems to be unnecessary, and after excluding these adjustments, for example with the modification

  • src/ICE/iceistate.F90

     
    416416            ELSEWHERE                ;   z2d(:,:) = 1._wp   ;   END WHERE 
    417417            ! 
    418418            DO jk = 1,jpkm1                     ! adjust initial vertical scale factors                 
    419                e3t_n(:,:,jk) = e3t_0(:,:,jk) * z2d(:,:) 
     419               e3t_n(:,:,jk) = e3t_0(:,:,jk) * ( z2d(:,:) * tmask(:,:,jk) - ( tmask(:,:,jk) - 1.0_wp ) ) 
    420420               e3t_b(:,:,jk) = e3t_n(:,:,jk) 
    421421               e3t_a(:,:,jk) = e3t_n(:,:,jk) 
    422422            END DO 

the restartability test is successful.

Commit History (1)

ChangesetAuthorTimeChangeLog
15405smueller2021-10-19T20:29:49+02:00

Correction of the initial vertical-scale-factor adjustment due to embedded sea ice (ticket #2729)

Change History (4)

comment:1 Changed 3 years ago by smueller

It has been pointed out that the adjustment of the vertical scale factors at source:/NEMO/releases/r4.0/r4.0-HEAD/src/ICE/iceistate.F90@14026#L419 (with and without the fix suggested above) ignores under-ice-shelf cavities. This is already being addressed in the context of ticket #2487 (see changeset [13180]).

comment:2 Changed 3 years ago by smueller

In 15405:

Error: Failed to load processor CommitTicketReference
No macro or processor named 'CommitTicketReference' found

comment:3 Changed 3 years ago by smueller

  • Owner set to smueller
  • Status changed from new to assigned

comment:4 Changed 3 years ago by smueller

  • Resolution set to fixed
  • Status changed from assigned to closed

source:/NEMO/releases/r4.0/r4.0-HEAD@15405 has passed the standard SETTE tests.

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