Bug in traldf_iso.F90 in the AR5 diagnostics

[gm]

An error has been introduced in the AR5 diagnostic of the diffusive heat flux associated with the isoneutral diffusion (traldf_iso.F90 module). Apparently a copy/past has been made from the traldf_eiv.F90. Unfortunately it is not the same diagnostics. In traldf_eiv, the bolus velocity is computed, so the bolus induced heat transport is obtained by multiplying the bolus velocity by the temperature and the surface of the lateral cell. In traldf_iso, the horizontal component of the isoneutral fluxes is computed (zftu,zftv), so only a vertical sum is needed.

CAUTION : the bug all concern the CMIP5_IPSL branch as well as V3.3beta. In the v3.3beta, both traldf_iso.F90 and traldf_iso_grif.F90 are affected.

Note that the correction has already been made in v3.3beta (see changeset:2450)

The following lines:

#if defined key_diaar5
      zztmp = 0.5 * rau0 * rcp 
      z2d(:,:) = 0.e0 
      DO jk = 1, jpkm1
         DO jj = 2, jpjm1
            DO ji = fs_2, fs_jpim1   ! vector opt.
               z2d(ji,jj) = z2d(ji,jj) + zztmp * zftu(ji,jj,jk) * ( tn(ji,jj,jk) + tn(ji+1,jj,jk) ) * e1u(ji,jj) * fse3u(ji,jj,jk) 
            END DO
         END DO
      END DO
      CALL lbc_lnk( z2d, 'U', -1. )
      CALL iom_put( "udiff_heattr", z2d )                  ! heat transport in i-direction
      z2d(:,:) = 0.e0 
      DO jk = 1, jpkm1
         DO jj = 2, jpjm1
            DO ji = fs_2, fs_jpim1   ! vector opt.
               z2d(ji,jj) = z2d(ji,jj) + zztmp * zftv(ji,jj,jk) * ( tn(ji,jj,jk) + tn(ji,jj+1,jk) ) * e2v(ji,jj) * fse3v(ji,jj,jk) 
            END DO
         END DO
      END DO
      CALL lbc_lnk( z2d, 'V', -1. )
      CALL iom_put( "vdiff_heattr", z2d )                  !  heat transport in i-direction
#endif

should be replaced by:

#if defined key_diaar5
      zztmp = rau0 * rcp 
      z2d(:,:) = 0.e0 
      DO jk = 1, jpkm1
         DO jj = 2, jpjm1
            DO ji = fs_2, fs_jpim1   ! vector opt.
               z2d(ji,jj) = z2d(ji,jj) + zftu(ji,jj,jk)
            END DO
         END DO
      END DO
      z2d(:,:) = z2d(:,:) * zztmp
      CALL lbc_lnk( z2d, 'U', -1. )
      CALL iom_put( "udiff_heattr", z2d )                  ! heat transport in i-direction
      DO jk = 1, jpkm1
         DO jj = 2, jpjm1
            DO ji = fs_2, fs_jpim1   ! vector opt.
               z2d(ji,jj) = z2d(ji,jj) + zftv(ji,jj,jk) 
            END DO
         END DO
      END DO
      z2d(:,:) = z2d(:,:) * zztmp
      CALL lbc_lnk( z2d, 'V', -1. )
      CALL iom_put( "vdiff_heattr", z2d )                  !  heat transport in i-direction
#endif

[cetlod]

(*) array z2d(:,:) must be reset to zero before compute the heat transport in j-direction

• Correction is made in v3.3beta, see changeset:2469
• Done in v3.2 for consolidation, see changeset:2468

[nicolasmartin]

Milestone 2010 Stream 1: User Interfaces deleted