Add a factor of 2 when adding Kv_slow into Kv_add

NOAA-GFDL · Apr 19, 2018 · 191b5be · 191b5be
1 parent 3385857
commit 191b5be
Showing 1 changed file with 7 additions and 6 deletions.
diff --git a/src/parameterizations/vertical/MOM_vert_friction.F90 b/src/parameterizations/vertical/MOM_vert_friction.F90
@@ -1165,16 +1165,17 @@ subroutine find_coupling_coef(a, hvel, do_i, h_harm, bbl_thick, kv_bbl, z_i, h_m
 
   ! add "slow" varying vertical viscosity (e.g., from background, tidal etc)
   if (associated(visc%Kv_slow)) then
+    ! GMM/ A factor of 2 is also needed here, see comment above from BGR.
     if (work_on_u) then
       do K=2,nz ; do i=is,ie ; if (do_i(i)) then
-        Kv_add(i,K) = Kv_add(i,K) + 0.5 * (visc%Kv_slow(i,j,k) + visc%Kv_slow(i+1,j,k))
+        Kv_add(i,K) = Kv_add(i,K) + 1.0 * (visc%Kv_slow(i,j,k) + visc%Kv_slow(i+1,j,k))
       endif ; enddo ; enddo
       if (do_OBCs) then
         do I=is,ie ; if (do_i(I) .and. (OBC%segnum_u(I,j) /= OBC_NONE)) then
           if (OBC%segment(OBC%segnum_u(I,j))%direction == OBC_DIRECTION_E) then
-            do K=2,nz ; Kv_add(i,K) = Kv_add(i,K) + visc%Kv_slow(i,j,k) ; enddo
+            do K=2,nz ; Kv_add(i,K) = Kv_add(i,K) + 2. * visc%Kv_slow(i,j,k) ; enddo
           elseif (OBC%segment(OBC%segnum_u(I,j))%direction == OBC_DIRECTION_W) then
-            do K=2,nz ; Kv_add(i,K) = Kv_add(i,K) + visc%Kv_slow(i+1,j,k) ; enddo
+            do K=2,nz ; Kv_add(i,K) = Kv_add(i,K) + 2. * visc%Kv_slow(i+1,j,k) ; enddo
           endif
         endif ; enddo
       endif
@@ -1183,14 +1184,14 @@ subroutine find_coupling_coef(a, hvel, do_i, h_harm, bbl_thick, kv_bbl, z_i, h_m
       endif ; enddo ; enddo
     else
       do K=2,nz ; do i=is,ie ; if (do_i(i)) then
-        Kv_add(i,K) = Kv_add(i,K) + 0.5*(visc%Kv_slow(i,j,k) + visc%Kv_slow(i,j+1,k))
+        Kv_add(i,K) = Kv_add(i,K) + 1.0*(visc%Kv_slow(i,j,k) + visc%Kv_slow(i,j+1,k))
       endif ; enddo ; enddo
       if (do_OBCs) then
         do i=is,ie ; if (do_i(i) .and. (OBC%segnum_v(i,J) /= OBC_NONE)) then
           if (OBC%segment(OBC%segnum_v(i,J))%direction == OBC_DIRECTION_N) then
-            do K=2,nz ; Kv_add(i,K) = Kv_add(i,K) + visc%Kv_slow(i,j,k) ; enddo
+            do K=2,nz ; Kv_add(i,K) = Kv_add(i,K) + 2. * visc%Kv_slow(i,j,k) ; enddo
           elseif (OBC%segment(OBC%segnum_v(i,J))%direction == OBC_DIRECTION_S) then
-            do K=2,nz ; Kv_add(i,K) = Kv_add(i,K) + visc%Kv_slow(i,j+1,k) ; enddo
+            do K=2,nz ; Kv_add(i,K) = Kv_add(i,K) + 2. * visc%Kv_slow(i,j+1,k) ; enddo
           endif
         endif ; enddo
       endif