module ghg_data 2,8
!------------------------------------------------------------------------------------------------
! Purpose:
! Provide default distributions of CH4, N2O, CFC11 and CFC12 to the radiation routines.
! **NOTE** CO2 is assumed by the radiation to a be constant value. This value is
! currently supplied directly by the chem_surfvals module.
!
! Revision history:
! 2004-08-29 B. Eaton Create CAM interface to trcmix.
!------------------------------------------------------------------------------------------------
use shr_kind_mod
, only: r8 => shr_kind_r8
use ppgrid, only: pcols, pver, begchunk, endchunk
use physics_types, only: physics_state
use physconst, only: mwdry, mwch4, mwn2o, mwf11, mwf12, mwco2
use chem_surfvals, only: chem_surfvals_get, chem_surfvals_co2_rad
use abortutils, only: endrun
use error_messages, only: handle_err
use phys_buffer, only: pbuf_add, pbuf_fld, pbuf_size_max
implicit none
private
save
! Public interfaces
public ::&
ghg_data_register, &! register ghg's with pbuf
ghg_data_timestep_init ! place data model of ghg's in pbuf
! Private variables
real(r8) :: rmwn2o ! = mwn2o/mwdry ! ratio of molecular weight n2o to dry air
real(r8) :: rmwch4 ! = mwch4/mwdry ! ratio of molecular weight ch4 to dry air
real(r8) :: rmwf11 ! = mwf11/mwdry ! ratio of molecular weight cfc11 to dry air
real(r8) :: rmwf12 ! = mwf12/mwdry ! ratio of molecular weight cfc12 to dry air
real(r8) :: rmwco2 ! = mwco2/mwdry ! ratio of molecular weights of co2 to dry air
integer, parameter :: ncnst = 6 ! number of constituents
character(len=8), dimension(ncnst), parameter :: &
cnst_names = (/'N2O ', 'CH4 ', 'CFC11', 'CFC12', 'CO2 ', 'O2 '/) ! constituent names
integer :: pbuf_idx(ncnst)
!================================================================================================
contains
!================================================================================================
subroutine ghg_data_register() 1,1
!-------------------------------------------------------------------------------
! register ghg's with pbuf
!-------------------------------------------------------------------------------
integer iconst
do iconst = 1,ncnst
call pbuf_add(cnst_names(iconst),'physpkg',1,pver,1,pbuf_idx(iconst))
enddo
end subroutine ghg_data_register
subroutine ghg_data_timestep_init(pbuf,state) 1,3
!-------------------------------------------------------------------------------
! place data model of ghg's in pbuf at each timestep
!-------------------------------------------------------------------------------
use ppgrid, only: begchunk, endchunk
use physics_types, only: physics_state
type(pbuf_fld), intent(inout), dimension(pbuf_size_max) :: pbuf ! physics buffer
type(physics_state), intent(in), dimension(begchunk:endchunk) :: state
integer iconst
integer lchnk
rmwn2o = mwn2o/mwdry ! ratio of molecular weight n2o to dry air
rmwch4 = mwch4/mwdry ! ratio of molecular weight ch4 to dry air
rmwf11 = mwf11/mwdry ! ratio of molecular weight cfc11 to dry air
rmwf12 = mwf12/mwdry ! ratio of molecular weight cfc12 to dry air
rmwco2 = mwco2/mwdry ! ratio of molecular weights of co2 to dry air
do iconst = 1,ncnst
!$OMP PARALLEL DO PRIVATE (LCHNK)
do lchnk = begchunk, endchunk
call trcmix(cnst_names(iconst), state(lchnk)%ncol, &
state(lchnk)%lat, state(lchnk)%pmid, &
pbuf(pbuf_idx(iconst))%fld_ptr(1,:,:,lchnk,1))
enddo
enddo
end subroutine ghg_data_timestep_init
!================================================================================================
subroutine trcmix(name, ncol, clat, pmid, q) 1,6
!-----------------------------------------------------------------------
!
! Purpose:
! Specify zonal mean mass mixing ratios of CH4, N2O, CFC11 and
! CFC12
!
! Method:
! Distributions assume constant mixing ratio in the troposphere
! and a decrease of mixing ratio in the stratosphere. Tropopause
! defined by ptrop. The scale height of the particular trace gas
! depends on latitude. This assumption produces a more realistic
! stratospheric distribution of the various trace gases.
!
! Author: J. Kiehl
!
!-----------------------------------------------------------------------
! Arguments
character(len=*), intent(in) :: name ! constituent name
integer, intent(in) :: ncol ! number of columns
real(r8), intent(in) :: clat(pcols) ! latitude in radians for columns
real(r8), intent(in) :: pmid(pcols,pver) ! model pressures
real(r8), intent(out) :: q(pcols,pver) ! constituent mass mixing ratio
integer i ! longitude loop index
integer k ! level index
real(r8) coslat(pcols) ! cosine of latitude
real(r8) dlat ! latitude in degrees
real(r8) ptrop ! pressure level of tropopause
real(r8) pratio ! pressure divided by ptrop
real(r8) trop_mmr ! tropospheric mass mixing ratio
real(r8) scale ! pressure scale height
!-----------------------------------------------------------------------
do i = 1, ncol
coslat(i) = cos(clat(i))
end do
if (name == 'O2') then
q = chem_surfvals_get('O2MMR')
else if (name == 'CO2') then
q = chem_surfvals_co2_rad()
else if (name == 'CH4') then
! set tropospheric mass mixing ratios
trop_mmr = rmwch4 * chem_surfvals_get('CH4VMR')
do k = 1,pver
do i = 1,ncol
! set stratospheric scale height factor for gases
dlat = abs(57.2958_r8 * clat(i))
if(dlat.le.45.0_r8) then
scale = 0.2353_r8
else
scale = 0.2353_r8 + 0.0225489_r8 * (dlat - 45)
end if
! pressure of tropopause
ptrop = 250.0e2_r8 - 150.0e2_r8*coslat(i)**2.0_r8
! determine output mass mixing ratios
if (pmid(i,k) >= ptrop) then
q(i,k) = trop_mmr
else
pratio = pmid(i,k)/ptrop
q(i,k) = trop_mmr * (pratio)**scale
end if
end do
end do
else if (name == 'N2O') then
! set tropospheric mass mixing ratios
trop_mmr = rmwn2o * chem_surfvals_get('N2OVMR')
do k = 1,pver
do i = 1,ncol
! set stratospheric scale height factor for gases
dlat = abs(57.2958_r8 * clat(i))
if(dlat.le.45.0_r8) then
scale = 0.3478_r8 + 0.00116_r8 * dlat
else
scale = 0.4000_r8 + 0.013333_r8 * (dlat - 45)
end if
! pressure of tropopause
ptrop = 250.0e2_r8 - 150.0e2_r8*coslat(i)**2.0_r8
! determine output mass mixing ratios
if (pmid(i,k) >= ptrop) then
q(i,k) = trop_mmr
else
pratio = pmid(i,k)/ptrop
q(i,k) = trop_mmr * (pratio)**scale
end if
end do
end do
else if (name == 'CFC11') then
! set tropospheric mass mixing ratios
trop_mmr = rmwf11 * chem_surfvals_get('F11VMR')
do k = 1,pver
do i = 1,ncol
! set stratospheric scale height factor for gases
dlat = abs(57.2958_r8 * clat(i))
if(dlat.le.45.0_r8) then
scale = 0.7273_r8 + 0.00606_r8 * dlat
else
scale = 1.00_r8 + 0.013333_r8 * (dlat - 45)
end if
! pressure of tropopause
ptrop = 250.0e2_r8 - 150.0e2_r8*coslat(i)**2.0_r8
! determine output mass mixing ratios
if (pmid(i,k) >= ptrop) then
q(i,k) = trop_mmr
else
pratio = pmid(i,k)/ptrop
q(i,k) = trop_mmr * (pratio)**scale
end if
end do
end do
else if (name == 'CFC12') then
! set tropospheric mass mixing ratios
trop_mmr = rmwf12 * chem_surfvals_get('F12VMR')
do k = 1,pver
do i = 1,ncol
! set stratospheric scale height factor for gases
dlat = abs(57.2958_r8 * clat(i))
if(dlat.le.45.0_r8) then
scale = 0.4000_r8 + 0.00222_r8 * dlat
else
scale = 0.50_r8 + 0.024444_r8 * (dlat - 45)
end if
! pressure of tropopause
ptrop = 250.0e2_r8 - 150.0e2_r8*coslat(i)**2.0_r8
! determine output mass mixing ratios
if (pmid(i,k) >= ptrop) then
q(i,k) = trop_mmr
else
pratio = pmid(i,k)/ptrop
q(i,k) = trop_mmr * (pratio)**scale
end if
end do
end do
end if
end subroutine trcmix
end module ghg_data