source: trunk/src/ohreaction.f90 @ 28

Last change on this file since 28 was 4, checked in by mlanger, 9 years ago
File size: 8.1 KB
Line 
1!**********************************************************************
2! Copyright 1998,1999,2000,2001,2002,2005,2007,2008,2009,2010         *
3! Andreas Stohl, Petra Seibert, A. Frank, Gerhard Wotawa,             *
4! Caroline Forster, Sabine Eckhardt, John Burkhart, Harald Sodemann   *
5!                                                                     *
6! This file is part of FLEXPART.                                      *
7!                                                                     *
8! FLEXPART is free software: you can redistribute it and/or modify    *
9! it under the terms of the GNU General Public License as published by*
10! the Free Software Foundation, either version 3 of the License, or   *
11! (at your option) any later version.                                 *
12!                                                                     *
13! FLEXPART is distributed in the hope that it will be useful,         *
14! but WITHOUT ANY WARRANTY; without even the implied warranty of      *
15! MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the       *
16! GNU General Public License for more details.                        *
17!                                                                     *
18! You should have received a copy of the GNU General Public License   *
19! along with FLEXPART.  If not, see <http://www.gnu.org/licenses/>.   *
20!**********************************************************************
21
22subroutine ohreaction(itime,ltsample,loutnext)
23  !                     i      i        i
24  !*****************************************************************************
25  !                                                                            *
26  !                                                                            *
27  !    Author: S. Eckhardt                                                     *
28  !                                                                            *
29  !    June 2007                                                               *
30  !                                                                            *
31  !                                                                            *
32  !*****************************************************************************
33  ! Variables:                                                                 *
34  ! ix,jy              indices of output grid cell for each particle           *
35  ! itime [s]          actual simulation time [s]                              *
36  ! jpart              particle index                                          *
37  ! ldeltat [s]        interval since radioactive decay was computed           *
38  ! loutnext [s]       time for which gridded deposition is next output        *
39  ! loutstep [s]       interval at which gridded deposition is output          *
40  ! oh_average [mol/m^3]   OH Concentration                                    *
41  ! ltsample [s]       interval over which mass is deposited                   *
42  !                                                                            *
43  !*****************************************************************************
44
45  use oh_mod
46  use par_mod
47  use com_mod
48
49  implicit none
50
51  integer :: jpart,itime,ltsample,loutnext,ldeltat,j,k,ix,jy
52  integer :: ngrid,il,interp_time,n,mm,indz,i
53  integer :: jjjjmmdd,ihmmss,OHx,OHy,dOHx,dOHy,OHz
54  real :: xtn,ytn,oh_average
55  !real oh_diurn_var,sum_ang
56  !real zenithangle, ang
57  real :: restmass,ohreacted,OHinc
58  real :: xlon, ylat, gas_const, act_energy
59  real :: ohreact_temp_corr, act_temp
60  real,parameter :: smallnum = tiny(0.0) ! smallest number that can be handled
61  real(kind=dp) :: jul
62
63  ! Compute interval since radioactive decay of deposited mass was computed
64  !************************************************************************
65
66  gas_const=8.314 ! define gas constant
67  act_energy=10000 ! activation energy
68
69  !write(*,*) 'OH reaction n:',n,ohreact(1)
70  if (itime.le.loutnext) then
71    ldeltat=itime-(loutnext-loutstep)
72  else                                  ! first half of next interval
73    ldeltat=itime-loutnext
74  endif
75
76
77    dOHx=360/(maxxOH-1)
78    dOHy=180/(maxyOH-1)
79
80    jul=bdate+real(itime,kind=dp)/86400._dp
81    call caldate(jul,jjjjmmdd,ihmmss)
82    mm=int((jjjjmmdd-(jjjjmmdd/10000)*10000)/100)
83
84    do jpart=1,numpart
85
86  ! Determine which nesting level to be used
87  !*****************************************
88
89    ngrid=0
90    do j=numbnests,1,-1
91      if ((xtra1(jpart).gt.xln(j)).and.(xtra1(jpart).lt.xrn(j)).and. &
92           (ytra1(jpart).gt.yln(j)).and.(ytra1(jpart).lt.yrn(j))) then
93        ngrid=j
94        goto 23
95      endif
96    end do
9723   continue
98
99
100  ! Determine nested grid coordinates
101  !**********************************
102
103    if (ngrid.gt.0) then
104      xtn=(xtra1(jpart)-xln(ngrid))*xresoln(ngrid)
105      ytn=(ytra1(jpart)-yln(ngrid))*yresoln(ngrid)
106      ix=int(xtn)
107      jy=int(ytn)
108    else
109      ix=int(xtra1(jpart))
110      jy=int(ytra1(jpart))
111    endif
112
113  n=2
114  if (abs(memtime(1)-interp_time).lt.abs(memtime(2)-interp_time)) &
115       n=1
116
117  do i=2,nz
118    if (height(i).gt.ztra1(jpart)) then
119      indz=i-1
120      goto 6
121    endif
122  end do
1236   continue
124
125  ! The concentration from the nearest available gridcell is taken
126  ! get OH concentration for the specific month and solar angle
127
128  !  write(*,*) OH_field(1,1,1,1),OH_field(10,1,1,10)
129  !  write(*,*) OH_field(1,maxxOH-1,maxyOH-1,1)
130  !  write(*,*) OH_field(10,maxxOH-1,maxyOH-1,10)
131  !  write(*,*) OH_field_height(1,10,4,1),OH_field_height(10,4,10,10)
132  !  write(*,*) OH_field_height(1,maxxOH-1,maxyOH-1,1)
133  !  write(*,*) OH_field_height(10,maxxOH-1,maxyOH-1,10)
134    interp_time=nint(itime-0.5*ltsample)
135
136  ! World coordinates
137    xlon=xtra1(jpart)*dx+xlon0
138    if (xlon.gt.180) then
139       xlon=xlon-360
140    endif
141    ylat=ytra1(jpart)*dy+ylat0
142  ! get position in the OH field - assume that the OH field is global
143    OHx=(180+xlon-1)/dOHx
144    OHy=(90+ylat-1)/dOHy
145  !  sum_ang=0
146  ! get the level of the OH height field were the actual particle is in
147  ! ztra1 is the z-coordinate of the trajectory above model orography in m
148  ! OH_field_height is the heigth of the OH field above orography
149      OHz=maxzOH
150  ! assume equally distrib. OH field, OH_field_height gives the middle of
151  ! the z coordinate
152      OHinc=(OH_field_height(3)-OH_field_height(2))/2
153      do il=2,maxzOH+1
154        if ((OH_field_height(il-1)+OHinc).gt.ztra1(jpart)) goto 26
155      end do
15626     continue
157
158     OHz=il-1
159  !   loop was not interrupted il would be 8 (9-1)
160     if (OHz.gt.maxzOH) OHz=7
161  !   write (*,*) 'OH height: '
162  !    +        ,ztra1(jpart),jpart,OHz,OH_field_height(OHz),OHinc,
163  !    +        OH_field_height
164
165    oh_average=OH_field(mm,OHx,OHy,OHz)
166    if (oh_average.gt.smallnum) then
167  !**********************************************************
168  ! if there is noOH concentration no reaction
169  ! for performance reason take average concentration and
170  ! ignore diurnal variation
171  ! do 28 il=1,24
172  !      ang=70-zenithangle(ylat,xlon,jul+(24-il)/24.)
173  !      if (ang.lt.0) then
174  !          ang=0
175  !      endif
176  !      sum_ang=sum_ang+ang
177  !28         enddo
178  !    oh_diurn_var=(ang/sum_ang)*(oh_average*24)
179  !    oh_average=oh_diurn_var
180  !**********************************************************
181
182
183  !    Computation of the OH reaction
184  !**********************************************************
185    act_temp=tt(ix,jy,indz,n)
186
187    do k=1,nspec                                  ! loop over species
188      if (ohreact(k).gt.0.) then
189        ohreact_temp_corr=ohreact(k)*oh_average* &
190             exp((act_energy/gas_const)*(1/298.15-1/act_temp))
191        ohreacted=xmass1(jpart,k)* &
192             (1.-exp(-1*ohreact_temp_corr*abs(ltsample)))
193  !      new particle mass:
194        restmass = xmass1(jpart,k)-ohreacted
195        if (restmass .gt. smallnum) then
196          xmass1(jpart,k)=restmass
197  !   write (104) xlon,ylat,ztra1(jpart),k,oh_diurn_var,jjjjmmdd,
198  !    +               ihmmss,restmass,ohreacted
199        else
200          xmass1(jpart,k)=0.
201        endif
202  !      write (*,*) 'restmass: ',restmass
203      else
204        ohreacted=0.
205      endif
206    end do
207
208  endif
209  !endif OH concentration gt 0
210    end do
211  !continue loop over all particles
212
213end subroutine ohreaction
Note: See TracBrowser for help on using the repository browser.
hosted by ZAMG