anchor.diff:  
   ! Input
       integer, parameter :: rb = selected_real_kind(12)
  -!     integer(kind=im), intent(in) :: iplon
       integer(kind=im), intent(in) :: ncol            ! number of columns
       integer(kind=im), intent(in) :: nlay            ! number of model layers
       integer(kind=im), intent(inout) :: icld         ! Cloud overlap method
  
positive.code: ! see _rrtm_radiation for the python that prepares these arguments...
  subroutine driver &
      (ncol, nlay, icld, &
      permuteseed, irng, idrv, play, plev, &
      tlay, tlev, tsfc, h2ovmr, o3vmr, co2vmr, ch4vmr, n2ovmr, &
      o2vmr, cfc11vmr, cfc12vmr, cfc22vmr, ccl4vmr, &
      emis, &
      inflglw, iceflgslw, liqflglw, tauc, cldfrac, &
      ciwp, clwp, reic, relq, &
      tauaer, &
      uflx, dflx, hr, uflxc, dflxc, hrc, duflx_dt, duflxc_dt)
  
  ! Modules
  
negative.code:                                                          ! with respect to surface temperature
  
      ! Local
      !   These quantities are computed by McICA
      real(kind=rb) :: cldfmcl(ngptlw,ncol,nlay)    ! cloud fraction [mcica]
      real(kind=rb) :: ciwpmcl(ngptlw,ncol,nlay)    ! in-cloud ice water path [mcica]
      real(kind=rb) :: clwpmcl(ngptlw,ncol,nlay)    ! in-cloud liquid water path [mcica]
      real(kind=rb) :: reicmcl(ncol,nlay)           ! ice partcle size (microns)  [mcica]
      real(kind=rb) :: relqmcl(ncol,nlay)           ! liquid particle size (microns) [mcica]
      real(kind=rb) :: taucmcl(ngptlw,ncol,nlay)    ! in-cloud optical depth [mcica]
  
      ! Call the Monte Carlo Independent Column Approximation
      !   (McICA, Pincus et al., JC, 2003)
      call mcica_subcol_lw(1, ncol, nlay, icld, permuteseed, irng, play, &
                         cldfrac, ciwp, clwp, reic, relq, tauc, cldfmcl, &
                         ciwpmcl, clwpmcl, reicmcl, relqmcl, taucmcl)
      !  Call the RRTMG_LW driver to compute radiative fluxes
      call rrtmg_lw(ncol    ,nlay    ,icld    ,idrv    , &
               play    ,plev    ,tlay    ,tlev    ,tsfc    , &
               h2ovmr  ,o3vmr   ,co2vmr  ,ch4vmr  ,n2ovmr  ,o2vmr , &
  