Index: NEMO/branches/2020/KERNEL-03_Storkey_Coward_RK3_stage2/src/OCE/TRA/traadv.F90
===================================================================
--- NEMO/branches/2020/KERNEL-03_Storkey_Coward_RK3_stage2/src/OCE/TRA/traadv.F90	(revision 12391)
+++ NEMO/branches/2020/KERNEL-03_Storkey_Coward_RK3_stage2/src/OCE/TRA/traadv.F90	(revision 12397)
@@ -92,9 +92,4 @@
       IF( ln_timing )   CALL timing_start('tra_adv')
       !
-      !                                          ! set time step
-      IF( neuler == 0 .AND. kt == nit000 ) THEN   ;   r2dt =         rdt   ! at nit000             (Euler)
-      ELSEIF( kt <= nit000 + 1 )           THEN   ;   r2dt = 2._wp * rdt   ! at nit000 or nit000+1 (Leapfrog)
-      ENDIF
-      !
       !                                         !==  effective transport  ==!
       zuu(:,:,jpk) = 0._wp
Index: NEMO/branches/2020/KERNEL-03_Storkey_Coward_RK3_stage2/src/OCE/TRA/traatf.F90
===================================================================
--- NEMO/branches/2020/KERNEL-03_Storkey_Coward_RK3_stage2/src/OCE/TRA/traatf.F90	(revision 12391)
+++ NEMO/branches/2020/KERNEL-03_Storkey_Coward_RK3_stage2/src/OCE/TRA/traatf.F90	(revision 12397)
@@ -113,9 +113,4 @@
       IF( ln_bdy )   CALL bdy_tra( kt, Kbb, pts, Kaa )  ! BDY open boundaries
  
-      ! set time step size (Euler/Leapfrog)
-      IF( neuler == 0 .AND. kt == nit000 ) THEN   ;   r2dt =        rdt   ! at nit000             (Euler)
-      ELSEIF( kt <= nit000 + 1 )           THEN   ;   r2dt = 2._wp* rdt   ! at nit000 or nit000+1 (Leapfrog)
-      ENDIF
-
       ! trends computation initialisation
       IF( l_trdtra )   THEN                    
@@ -144,5 +139,5 @@
       ENDIF
 
-      IF( neuler == 0 .AND. kt == nit000 ) THEN       ! Euler time-stepping 
+      IF( l_1st_euler ) THEN       ! Euler time-stepping 
          !
          IF (l_trdtra .AND. .NOT. ln_linssh ) THEN   ! Zero Asselin filter contribution must be explicitly written out since for vvl
Index: NEMO/branches/2020/KERNEL-03_Storkey_Coward_RK3_stage2/src/OCE/TRA/traldf_iso.F90
===================================================================
--- NEMO/branches/2020/KERNEL-03_Storkey_Coward_RK3_stage2/src/OCE/TRA/traldf_iso.F90	(revision 12391)
+++ NEMO/branches/2020/KERNEL-03_Storkey_Coward_RK3_stage2/src/OCE/TRA/traldf_iso.F90	(revision 12397)
@@ -109,5 +109,5 @@
       REAL(wp) ::  zmsku, zahu_w, zabe1, zcof1, zcoef3   ! local scalars
       REAL(wp) ::  zmskv, zahv_w, zabe2, zcof2, zcoef4   !   -      -
-      REAL(wp) ::  zcoef0, ze3w_2, zsign, z2dt, z1_2dt   !   -      -
+      REAL(wp) ::  zcoef0, ze3w_2, zsign                 !   -      -
       REAL(wp), DIMENSION(jpi,jpj)     ::   zdkt, zdk1t, z2d
       REAL(wp), DIMENSION(jpi,jpj,jpk) ::   zdit, zdjt, zftu, zftv, ztfw 
@@ -129,9 +129,4 @@
          &                        iom_use("uadv_salttr") .OR. iom_use("vadv_salttr")  ) )   l_hst = .TRUE.
       !
-      !                                            ! set time step size (Euler/Leapfrog)
-      IF( neuler == 0 .AND. kt == nit000 ) THEN   ;   z2dt =     rdt      ! at nit000   (Euler)
-      ELSE                                        ;   z2dt = 2.* rdt      !             (Leapfrog)
-      ENDIF
-      z1_2dt = 1._wp / z2dt
       !
       IF( kpass == 1 ) THEN   ;   zsign =  1._wp      ! bilaplacian operator require a minus sign (eddy diffusivity >0)
@@ -178,6 +173,6 @@
                DO_3D_10_10( 2, jpkm1 )
                   ze3w_2 = e3w(ji,jj,jk,Kmm) * e3w(ji,jj,jk,Kmm)
-                  zcoef0 = z2dt * (  akz(ji,jj,jk) + ah_wslp2(ji,jj,jk) / ze3w_2  )
-                  akz(ji,jj,jk) = MAX( zcoef0 - 0.5_wp , 0._wp ) * ze3w_2 * z1_2dt
+                  zcoef0 = r2dt * (  akz(ji,jj,jk) + ah_wslp2(ji,jj,jk) / ze3w_2  )
+                  akz(ji,jj,jk) = MAX( zcoef0 - 0.5_wp , 0._wp ) * ze3w_2 * r1_2dt
                END_3D
            ENDIF
Index: NEMO/branches/2020/KERNEL-03_Storkey_Coward_RK3_stage2/src/OCE/TRA/traldf_triad.F90
===================================================================
--- NEMO/branches/2020/KERNEL-03_Storkey_Coward_RK3_stage2/src/OCE/TRA/traldf_triad.F90	(revision 12391)
+++ NEMO/branches/2020/KERNEL-03_Storkey_Coward_RK3_stage2/src/OCE/TRA/traldf_triad.F90	(revision 12397)
@@ -86,7 +86,7 @@
       INTEGER  ::  ip,jp,kp         ! dummy loop indices
       INTEGER  ::  ierr            ! local integer
-      REAL(wp) ::  zmsku, zabe1, zcof1, zcoef3          ! local scalars
-      REAL(wp) ::  zmskv, zabe2, zcof2, zcoef4          !   -      -
-      REAL(wp) ::  zcoef0, ze3w_2, zsign, z2dt, z1_2dt  !   -      -
+      REAL(wp) ::  zmsku, zabe1, zcof1, zcoef3    ! local scalars
+      REAL(wp) ::  zmskv, zabe2, zcof2, zcoef4    !   -      -
+      REAL(wp) ::  zcoef0, ze3w_2, zsign          !   -      -
       !
       REAL(wp) ::   zslope_skew, zslope_iso, zslope2, zbu, zbv
@@ -111,13 +111,9 @@
       l_hst = .FALSE.
       l_ptr = .FALSE.
-      IF( cdtype == 'TRA' .AND. ( iom_use( 'sophtldf' ) .OR. iom_use( 'sopstldf' ) ) )      l_ptr = .TRUE. 
-      IF( cdtype == 'TRA' .AND. ( iom_use("uadv_heattr") .OR. iom_use("vadv_heattr") .OR. &
-         &                        iom_use("uadv_salttr") .OR. iom_use("vadv_salttr")  ) )   l_hst = .TRUE.
-      !
-      !                                                        ! set time step size (Euler/Leapfrog)
-      IF( neuler == 0 .AND. kt == kit000 ) THEN   ;   z2dt =     rdt      ! at nit000   (Euler)
-      ELSE                                        ;   z2dt = 2.* rdt      !             (Leapfrog)
+      IF( cdtype == 'TRA' ) THEN
+         IF( iom_use( 'sophtldf' ) .OR. iom_use( 'sopstldf') )      l_ptr = .TRUE. 
+         IF( iom_use("uadv_heattr") .OR. iom_use("vadv_heattr") .OR.                   &
+         &   iom_use("uadv_salttr") .OR. iom_use("vadv_salttr")  )   l_hst = .TRUE.
       ENDIF
-      z1_2dt = 1._wp / z2dt
       !
       IF( kpass == 1 ) THEN   ;   zsign =  1._wp      ! bilaplacian operator require a minus sign (eddy diffusivity >0)
@@ -189,6 +185,6 @@
                DO_3D_10_10( 2, jpkm1 )
                   ze3w_2 = e3w(ji,jj,jk,Kmm) * e3w(ji,jj,jk,Kmm)
-                  zcoef0 = z2dt * (  akz(ji,jj,jk) + ah_wslp2(ji,jj,jk) / ze3w_2  )
-                  akz(ji,jj,jk) = MAX( zcoef0 - 0.5_wp , 0._wp ) * ze3w_2 * z1_2dt
+                  zcoef0 = r2dt * (  akz(ji,jj,jk) + ah_wslp2(ji,jj,jk) / ze3w_2  )
+                  akz(ji,jj,jk) = MAX( zcoef0 - 0.5_wp , 0._wp ) * ze3w_2 * r1_2dt
                END_3D
            ENDIF
Index: NEMO/branches/2020/KERNEL-03_Storkey_Coward_RK3_stage2/src/OCE/TRA/traqsr.F90
===================================================================
--- NEMO/branches/2020/KERNEL-03_Storkey_Coward_RK3_stage2/src/OCE/TRA/traqsr.F90	(revision 12391)
+++ NEMO/branches/2020/KERNEL-03_Storkey_Coward_RK3_stage2/src/OCE/TRA/traqsr.F90	(revision 12397)
@@ -135,6 +135,5 @@
       !                         !-----------------------------------!
       IF( kt == nit000 ) THEN          !==  1st time step  ==!
-!!gm case neuler  not taken into account....
-         IF( ln_rstart .AND. iom_varid( numror, 'qsr_hc_b', ldstop = .FALSE. ) > 0 ) THEN    ! read in restart
+         IF( ln_rstart .AND. iom_varid( numror, 'qsr_hc_b', ldstop = .FALSE. ) > 0  .AND. .NOT.l_1st_euler ) THEN    ! read in restart
             IF(lwp) WRITE(numout,*) '          nit000-1 qsr tracer content forcing field read in the restart file'
             z1_2 = 0.5_wp
Index: NEMO/branches/2020/KERNEL-03_Storkey_Coward_RK3_stage2/src/OCE/TRA/trazdf.F90
===================================================================
--- NEMO/branches/2020/KERNEL-03_Storkey_Coward_RK3_stage2/src/OCE/TRA/trazdf.F90	(revision 12391)
+++ NEMO/branches/2020/KERNEL-03_Storkey_Coward_RK3_stage2/src/OCE/TRA/trazdf.F90	(revision 12397)
@@ -64,8 +64,4 @@
          IF(lwp)WRITE(numout,*) 'tra_zdf : implicit vertical mixing on T & S'
          IF(lwp)WRITE(numout,*) '~~~~~~~ '
-      ENDIF
-      !
-      IF( neuler == 0 .AND. kt == nit000 ) THEN   ;   r2dt =      rdt   ! at nit000, =   rdt (restarting with Euler time stepping)
-      ELSEIF( kt <= nit000 + 1           ) THEN   ;   r2dt = 2. * rdt   ! otherwise, = 2 rdt (leapfrog)
       ENDIF
       !
