```
#include <misc.h>
#include <params.h>

subroutine qmassa(cwava   ,w       ,q3      ,pdel    ,hw1lat  , & 1,3
nlon    ,q0, lat)

!-----------------------------------------------------------------------
!
! Purpose:
! Calculate contribution of current latitude to mass of constituents
!
! Method:
!
! Author: J. Olson
!
!-----------------------------------------------------------------------
!
! \$Id: qmassa.F90,v 1.1.2.3 2004/03/10 23:02:09 bundy Exp \$
! \$Author: bundy \$
!
!-----------------------------------------------------------------------

use shr_kind_mod, only: r8 => shr_kind_r8
use pmgrid
use constituents, only: pcnst, pnats, cnst_get_type_byind

implicit none

!------------------------------Arguments--------------------------------
integer , intent(in)  :: nlon                 ! longitude dimension
real(r8), intent(in)  :: cwava                ! normalization factor    l/(g*plon)
real(r8), intent(in)  :: w                    ! gaussian weight this latitude
real(r8), intent(in)  :: q3(plond,plev,pcnst) ! constituents
real(r8), intent(in)  :: q0(plond,plev,pcnst) ! constituents at begining of time step
real(r8), intent(in)  :: pdel(plond,plev)     ! pressure diff between interfaces
real(r8), intent(out) :: hw1lat(pcnst)        ! accumulator
integer lat
!-----------------------------------------------------------------------
!
!---------------------------Local variables-----------------------------
integer i,k,m             ! longitude, level, constituent indices
real(r8) const            ! temporary constant
!-----------------------------------------------------------------------
!
! Integration factor (the 0.5 factor arises because gaussian weights sum to 2)
!
const = cwava*w*0.5
do m=1,pcnst
hw1lat(m) = 0.
end do
!
! Compute mass integral for water ONLY
!
do k=1,plev
do i=1,nlon
hw1lat(1) = hw1lat(1) + q3(i,k,1)*pdel(i,k)
end do
end do
!
! Compute mass integral for non-water constituents (on either WET or DRY basis)
!
do m=2,pcnst
if (cnst_get_type_byind(m).eq.'dry' ) then
do k=1,plev
do i=1,nlon
hw1lat(m) = hw1lat(m) + q3(i,k,m)*(1. - q0(i,k,1))*pdel(i,k)
end do
end do
else
do k=1,plev
do i=1,nlon
hw1lat(m) = hw1lat(m) + q3(i,k,m)*(1. - q3(i,k,1))*pdel(i,k)
end do
end do
end if
end do

do m = 1,pcnst
hw1lat(m) = hw1lat(m)*const
end do

return
end subroutine qmassa

```