PISCES P4Z reproducibility

Context

The SETTE ORCA2_ICE_PISCES and ORCA2_OFF_PISCES reproducibility tests of 77f25f31 (current head of branch_4.2) fail.

Analysis

Subroutine p4z_sed of module p4zsed contains a questionable assignment of a scalar value to a two-dimensional array inside a horizontal loop.

Fix

The default SETTE tests pass when the assignment of the scalar value to the whole array is replaced by its assignment to the corresponding array element,

--- a/src/TOP/PISCES/P4Z/p4zsed.F90
+++ b/src/TOP/PISCES/P4Z/p4zsed.F90
@@ -118,7 +118,7 @@ CONTAINS
                 !
               zflx = (  tr(ji,jj,ikt,jpgoc,Kbb) * zwsbio4(ji,jj)   &
                 &     + tr(ji,jj,ikt,jppoc,Kbb) * zwsbio3(ji,jj) ) * 1E6
-              zbureff = 0.013 + 0.53 * zflx**2 / ( 7.0 + zflx )**2 * MIN(gdepw(ji,jj,ikt+1,Kmm) / 1000.00, 1.0)
+              zbureff(ji,jj) = 0.013 + 0.53 * zflx**2 / ( 7.0 + zflx )**2 * MIN(gdepw(ji,jj,ikt+1,Kmm) / 1000.00, 1.0)
            ENDIF
          END_2D
          !