anchor.diff:              !                         this% kms : this% kme, &
               !                         this% jms : this% jme) )
   
  -            allocate(delta_dzdx(this% ims+1 : this% ime, &    ! can go to allocate_z_arrays ?
  -                                    this% kms : this% kme, &
  -                                    this% jms : this% jme) )         
  -            
  -            allocate(delta_dzdy(this% ims: this% ime, &
  -                                    this% kms : this% kme, &
  -                                    this% jms+1 : this% jme) )         
  +     
   
   
               ! do i = this%grid%kms, this%grid%kme
  
positive.code: 
          call io_write("zfr_u.nc", "zfr_u", zfr_u(:,:,:) ) ! check in plot
          
          print *, "zfr_u min/max: ", min(zfr_u), " / ", max(zfr_u)
  
          ! =>  But how to scale the winds with this??
  
  
negative.code:         ! type(boundary_t), intent(inout) :: forcing
          type(options_t), intent(in)     :: options
          real,            intent(in)     :: terrain_u(:,:), terrain_v(:,:),  dz_scl(:), H
          integer,         intent(in)     :: i, max_level
  
          real, allocatable :: forcing_terrain_u(:,:), forcing_terrain_v(:,:), delta_terrain(:,:)
          real :: s
  
          associate(ims => this%ims,      ime => this%ime,                        &
                    jms => this%jms,      jme => this%jme,                        &
                    kms => this%kms,      kme => this%kme,                        &
                    terrain               => this%terrain%data_2d,                &
                    forcing_terrain       => this%forcing_terrain%data_2d,        &
                    n                     =>  options%parameters%sleve_n,         & 
                    dzdx                  => this%dzdx,                           &
                    dzdy                  => this%dzdy,                           &
                    delta_dzdx            => this%delta_dzdx,                     & 
                    delta_dzdy            => this%delta_dzdy,                     & 
                    zfr_u                 => this%zfr_u,                          &
                    zfr_v                 => this%zfr_v )
                    ! z_level_ratio         => this%z_level_ratio,                  &
                    ! zr_u                  => this%zr_u,                           &
                    ! zr_v                  => this%zr_v)
  