anchor.diff:      !
       return
     end subroutine steady_state
  -  !-----------------------------------------------------------------------------
  -  !
  +
     !-----------------------------------------------------------------------------
     ! convert geopotential height to pressure
     subroutine geo2prs( &
  
positive.code:     !
      return
    end subroutine geo2prs
    !-----------------------------------------------------------------------------
    !
    !-----------------------------------------------------------------------------
    ! setting perturbation
    subroutine perturbation( &
  
negative.code:     real(PRCS_D), intent(in) :: geo(kdim)
      real(PRCS_D), intent(inout) :: prs(kdim)
      real(PRCS_D) :: dZ, dT, e
  
      e = exp(1.D0)
      prs(1) = p0
      ! guess pressure field upper k=0
  