one_equation_salt Function

  function one_equation_salt(this) result(salt)
    class(one_equation_melt), intent(in) :: this
    class(scalar_field), pointer         :: salt
      !! The value of the contribution made by melting/thermal
      !! transfer to the salt equation for a [[plume]]
    if (.not. allocated(this%forcing_values) .and. this%sal_forcing /= 0._r8) then
      error stop ('Melt values not calculated')
    end if
    salt => this%sal_forcing * this%forcing_values
  end function one_equation_salt