source: LMDZ6/branches/IPSLCM6.0.14/libf/phylmd/StratAer/micphy_tstep.F90 @ 3205

Last change on this file since 3205 was 3098, checked in by oboucher, 7 years ago

Cosmetic changes to the routine

File size: 7.1 KB
Line 
1SUBROUTINE micphy_tstep(pdtphys,tr_seri,t_seri,pplay,paprs,rh,is_strato)
2
3  USE dimphy, ONLY : klon,klev
4  USE aerophys
5  USE infotrac
6  USE phys_local_var_mod, ONLY: mdw, budg_3D_nucl, budg_3D_cond_evap, budg_h2so4_to_part, R2SO4, DENSO4, f_r_wet
7  USE nucleation_tstep_mod
8  USE cond_evap_tstep_mod
9  USE sulfate_aer_mod, ONLY : STRAACT
10  USE YOMCST, ONLY : RPI, RD, RG
11
12  IMPLICIT NONE
13
14  !--------------------------------------------------------
15
16  ! transfer variables when calling this routine
17  REAL,INTENT(IN)                               :: pdtphys ! Pas d'integration pour la physique (seconde)
18  REAL,DIMENSION(klon,klev,nbtr),INTENT(INOUT)  :: tr_seri ! Concentration Traceur [U/KgA]
19  REAL,DIMENSION(klon,klev),INTENT(IN)          :: t_seri  ! Temperature
20  REAL,DIMENSION(klon,klev),INTENT(IN)          :: pplay   ! pression pour le mileu de chaque couche (en Pa)
21  REAL,DIMENSION(klon,klev+1),INTENT(IN)        :: paprs   ! pression pour chaque inter-couche (en Pa)
22  REAL,DIMENSION(klon,klev),INTENT(IN)          :: rh      ! humidite relative
23  LOGICAL,DIMENSION(klon,klev),INTENT(IN)       :: is_strato
24
25  ! local variables in coagulation routine
26  INTEGER, PARAMETER        :: nbtstep=4  ! Max number of time steps in microphysics per time step in physics
27  INTEGER                   :: it,ilon,ilev,count_tstep
28  REAL                      :: rhoa !H2SO4 number density [molecules/cm3]
29  REAL                      :: ntot !total number of molecules in the critical cluster (ntot>4)
30  REAL                      :: x    ! molefraction of H2SO4 in the critical cluster     
31  REAL Vbin(nbtr_bin)
32  REAL a_xm, b_xm, c_xm
33  REAL PDT, dt
34  REAL H2SO4_init
35  REAL ACTSO4(klon,klev)
36  REAL RRSI(nbtr_bin)
37  REAL nucl_rate
38  REAL cond_evap_rate
39  REAL evap_rate
40  REAL FL(nbtr_bin)
41  REAL ASO4(nbtr_bin)
42  REAL DNDR(nbtr_bin)
43  REAL H2SO4_sat(nbtr_bin)
44
45  DO it=1,nbtr_bin
46    Vbin(it)=4.0*RPI*((mdw(it)/2.)**3)/3.0
47  ENDDO
48
49  !coefficients for H2SO4 density parametrization used for nucleation if ntot<4
50  a_xm = 0.7681724 + 1.*(2.1847140 + 1.*(7.1630022 + 1.*(-44.31447 + &
51       & 1.*(88.75606 + 1.*(-75.73729 + 1.*23.43228)))))
52  b_xm = 1.808225e-3 + 1.*(-9.294656e-3 + 1.*(-0.03742148 + 1.*(0.2565321 + &
53       & 1.*(-0.5362872 + 1.*(0.4857736 - 1.*0.1629592)))))
54  c_xm = -3.478524e-6 + 1.*(1.335867e-5 + 1.*(5.195706e-5 + 1.*(-3.717636e-4 + &
55       & 1.*(7.990811e-4 + 1.*(-7.458060e-4 + 1.*2.58139e-4 )))))
56
57  ! STRAACT (R2SO4, t_seri -> H2SO4 activity coefficient (ACTSO4)) for cond/evap
58  CALL STRAACT(ACTSO4)
59
60  ! compute particle radius in cm RRSI from diameter in m
61  DO it=1,nbtr_bin
62    RRSI(it)=mdw(it)/2.*100.
63  ENDDO
64
65  DO ilon=1, klon
66!
67!--initialisation of diagnostic
68  budg_h2so4_to_part(ilon)=0.0
69!
70  DO ilev=1, klev
71!
72!--initialisation of diagnostic
73  budg_3D_nucl(ilon,ilev)=0.0
74  budg_3D_cond_evap(ilon,ilev)=0.0
75!
76  ! only in the stratosphere
77  IF (is_strato(ilon,ilev)) THEN
78    ! initialize sulfur fluxes
79    H2SO4_init=tr_seri(ilon,ilev,id_H2SO4_strat)
80    ! adaptive timestep for nucleation and condensation
81    PDT=pdtphys
82    count_tstep=0
83    DO WHILE (PDT>0.0)
84      count_tstep=count_tstep+1
85      IF (count_tstep .GT. nbtstep)  EXIT
86      ! convert tr_seri(GASH2SO4) (in kg/kgA) to H2SO4 number density (in molecules/cm3)
87      rhoa=tr_seri(ilon,ilev,id_H2SO4_strat) &
88          & *pplay(ilon,ilev)/t_seri(ilon,ilev)/RD/1.E6/mH2SO4mol
89      ! compute nucleation rate in kg(H2SO4)/kgA/s
90      CALL nucleation_rate(rhoa,t_seri(ilon,ilev),pplay(ilon,ilev),rh(ilon,ilev), &
91             & a_xm,b_xm,c_xm,nucl_rate,ntot,x)
92      ! compute cond/evap rate in kg(H2SO4)/kgA/s
93      CALL condens_evapor_rate(rhoa,t_seri(ilon,ilev),pplay(ilon,ilev), &
94             & ACTSO4(ilon,ilev),R2SO4(ilon,ilev),DENSO4(ilon,ilev),f_r_wet(ilon,ilev), &
95             & RRSI,Vbin,FL,ASO4,DNDR)
96      ! consider only condensation (positive FL)
97      DO it=1,nbtr_bin
98        FL(it)=MAX(FL(it),0.)
99      ENDDO
100      ! compute total H2SO4 cond flux for all particles
101      cond_evap_rate=0.0
102      DO it=1, nbtr_bin
103        cond_evap_rate=cond_evap_rate+tr_seri(ilon,ilev,it+nbtr_sulgas)*FL(it)*mH2SO4mol
104      ENDDO
105      ! determine appropriate time step
106      dt=(H2SO4_init-H2SO4_sat(nbtr_bin))/float(nbtstep)/MAX(1.e-30, nucl_rate+cond_evap_rate) !cond_evap_rate pos. for cond. and neg. for evap.
107      IF (dt.LT.0.0) THEN
108        dt=PDT
109      ENDIF
110      dt=MIN(dt,PDT)
111      ! update H2SO4 concentration
112      tr_seri(ilon,ilev,id_H2SO4_strat)=MAX(0.,tr_seri(ilon,ilev,id_H2SO4_strat)-(nucl_rate+cond_evap_rate)*dt)
113      ! apply cond to bins
114      CALL cond_evap_part(dt,FL,ASO4,f_r_wet(ilon,ilev),RRSI,Vbin,tr_seri(ilon,ilev,:))
115      ! apply nucl. to bins
116      CALL nucleation_part(nucl_rate,ntot,x,dt,Vbin,tr_seri(ilon,ilev,:))
117      ! compute fluxes as diagnostic in [kg(S)/m2/layer/s] (now - for evap and + for cond)
118      budg_3D_cond_evap(ilon,ilev)=budg_3D_cond_evap(ilon,ilev)+mSatom/mH2SO4mol &
119               & *cond_evap_rate*(paprs(ilon,ilev)-paprs(ilon,ilev+1))/RG*dt/pdtphys
120      budg_3D_nucl(ilon,ilev)=budg_3D_nucl(ilon,ilev)+mSatom/mH2SO4mol &
121               & *nucl_rate*(paprs(ilon,ilev)-paprs(ilon,ilev+1))/RG*dt/pdtphys
122      ! update time step
123      PDT=PDT-dt
124    ENDDO
125    ! convert tr_seri(GASH2SO4) (in kg/kgA) to H2SO4 number density (in molecules/cm3)
126    rhoa=tr_seri(ilon,ilev,id_H2SO4_strat) &
127        & *pplay(ilon,ilev)/t_seri(ilon,ilev)/RD/1.E6/mH2SO4mol
128    ! compute cond/evap rate in kg(H2SO4)/kgA/s (now only evap for pdtphys)
129    CALL condens_evapor_rate(rhoa,t_seri(ilon,ilev),pplay(ilon,ilev), &
130           & ACTSO4(ilon,ilev),R2SO4(ilon,ilev),DENSO4(ilon,ilev),f_r_wet(ilon,ilev), &
131           & RRSI,Vbin,FL,ASO4,DNDR)
132    ! limit evaporation (negative FL) over one physics time step to H2SO4 content of the droplet
133    DO it=1,nbtr_bin
134      FL(it)=MAX(FL(it)*pdtphys,0.-ASO4(it))/pdtphys
135      ! consider only evap (negative FL)
136      FL(it)=MIN(FL(it),0.)
137    ENDDO
138    ! compute total H2SO4 evap flux for all particles
139    evap_rate=0.0
140    DO it=1, nbtr_bin
141      evap_rate=evap_rate+tr_seri(ilon,ilev,it+nbtr_sulgas)*FL(it)*mH2SO4mol
142    ENDDO
143    ! update H2SO4 concentration after evap
144    tr_seri(ilon,ilev,id_H2SO4_strat)=MAX(0.,tr_seri(ilon,ilev,id_H2SO4_strat)-evap_rate*pdtphys)
145    ! apply evap to bins
146    CALL cond_evap_part(pdtphys,FL,ASO4,f_r_wet(ilon,ilev),RRSI,Vbin,tr_seri(ilon,ilev,:))
147    ! compute fluxes as diagnostic in [kg(S)/m2/layer/s] (now - for evap and + for cond)
148    budg_3D_cond_evap(ilon,ilev)=budg_3D_cond_evap(ilon,ilev)+mSatom/mH2SO4mol &
149             & *evap_rate*(paprs(ilon,ilev)-paprs(ilon,ilev+1))/RG
150    ! compute vertically integrated flux due to the net effect of nucleation and condensation/evaporation
151    budg_h2so4_to_part(ilon)=budg_h2so4_to_part(ilon)+(H2SO4_init-tr_seri(ilon,ilev,id_H2SO4_strat)) &
152             & *mSatom/mH2SO4mol*(paprs(ilon,ilev)-paprs(ilon,ilev+1))/RG/pdtphys
153  ENDIF
154  ENDDO
155  ENDDO
156
157  IF (MINVAL(tr_seri).LT.0.0) THEN
158    DO ilon=1, klon
159    DO ilev=1, klev   
160    DO it=1, nbtr
161      IF (tr_seri(ilon,ilev,it).LT.0.0) THEN
162        PRINT *, 'micphy_tstep: negative concentration', tr_seri(ilon,ilev,it), ilon, ilev, it
163      ENDIF
164    ENDDO
165    ENDDO
166    ENDDO
167  ENDIF
168
169END SUBROUTINE micphy_tstep
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