diff --git a/src/core/MOM_variables.F90 b/src/core/MOM_variables.F90
index 4b85111a21..f7fa45f12c 100644
--- a/src/core/MOM_variables.F90
+++ b/src/core/MOM_variables.F90
@@ -228,6 +228,9 @@ module MOM_variables
                          !! at the interfaces between each layer, in m2 s-1.
     Kv_shear => NULL(), &!< The shear-driven turbulent vertical viscosity
                          !! at the interfaces between each layer, in m2 s-1.
+    Kv_slow  => NULL(), &!< The turbulent vertical viscosity component due to
+                         !! "slow" processes (e.g., tidal, background,
+                         !! convection etc).
     TKE_turb => NULL()  !< The turbulent kinetic energy per unit mass defined
                         !! at the interfaces between each layer, in m2 s-2.
 end type vertvisc_type
diff --git a/src/parameterizations/vertical/MOM_set_viscosity.F90 b/src/parameterizations/vertical/MOM_set_viscosity.F90
index 8ab4bafb75..19f956f1b1 100644
--- a/src/parameterizations/vertical/MOM_set_viscosity.F90
+++ b/src/parameterizations/vertical/MOM_set_viscosity.F90
@@ -1811,6 +1811,7 @@ subroutine set_visc_register_restarts(HI, GV, param_file, visc, restart_CS)
     allocate(visc%Kd_shear(isd:ied,jsd:jed,nz+1)) ; visc%Kd_shear(:,:,:) = 0.0
     allocate(visc%TKE_turb(isd:ied,jsd:jed,nz+1)) ; visc%TKE_turb(:,:,:) = 0.0
     allocate(visc%Kv_shear(isd:ied,jsd:jed,nz+1)) ; visc%Kv_shear(:,:,:) = 0.0
+    ! GMM, allocate visc%Kv_slow here?
 
     vd = var_desc("Kd_shear","m2 s-1","Shear-driven turbulent diffusivity at interfaces", &
                   hor_grid='h', z_grid='i')