anchor.diff:  
          rhogq(:,:,:,nq) = rhogq(:,:,:,nq) + TIME_DTL * frhogq(:,:,:)
   
  -       if (       nq >= NQW_STR &
  -            .AND. nq <= NQW_END ) then ! update total density
  -          rhog (:,:,:) = rhog (:,:,:) + TIME_DTL * frhogq(:,:,:)
  +       if ( UPDATE_TOT_DENS ) then
  +          if (       nq >= NQW_STR &
  +               .AND. nq <= NQW_END ) then ! update total density
  +             rhog (:,:,:) = rhog (:,:,:) + TIME_DTL * frhogq(:,:,:)
  +          endif
          endif
       enddo
   
  
positive.code:   integer, private, parameter :: I_RHOGE    = 6 ! Density x G^1/2 x gamma^2 x Internal Energy
    integer, private, parameter :: I_RHOGETOT = 7 ! Density x G^1/2 x gamma^2 x Total Energy
  
    !-----------------------------------------------------------------------------
  contains
    !-----------------------------------------------------------------------------
    subroutine forcing_setup
      use mod_adm, only: &
         ADM_proc_stop
      use mod_runconf, only: &
         AF_TYPE
      use mod_af_heldsuarez, only: &
  
negative.code:     use mod_af_dcmip2016, only: &
         AF_dcmip2016_init
      implicit none
  
      namelist /FORCING_PARAM/ &
         UPDATE_TOT_DENS
  
      integer :: ierr
      !---------------------------------------------------------------------------
  
      !--- read parameters
      write(ADM_LOG_FID,*)
      write(ADM_LOG_FID,*) '+++ Module[forcing]/Category[nhm]'
      rewind(ADM_CTL_FID)
      read(ADM_CTL_FID,nml=FORCING_PARAM,iostat=ierr)
      if ( ierr < 0 ) then
         write(ADM_LOG_FID,*) '*** FORCING_PARAM is not specified. use default.'
      elseif( ierr > 0 ) then
         write(*,          *) 'xxx Not appropriate names in namelist FORCING_PARAM. STOP.'
         write(ADM_LOG_FID,*) 'xxx Not appropriate names in namelist FORCING_PARAM. STOP.'
         call ADM_proc_stop
      endif
      write(ADM_LOG_FID,nml=FORCING_PARAM)
  
      write(ADM_LOG_FID,*) '+++ Artificial forcing type: ', trim(AF_TYPE)
      select case(AF_TYPE)
  