#include "tm5.inc" SUBROUTINE m7_equiz(kproma, kbdim, klev, & papp1, pttn, ptp1, & prelhum, pm6rp, pm6dry, & prhop, pww, paernl ) ! ! *m7_equiz* calculates the ambient radii of the sulphate particles ! ! Authors: ! -------- ! J. Wilson, E. Vignati, JRC/EI (original source) 05/2000 ! P. Stier, MPI (f90-version, changes, comments) 2001 ! ! Purpose: ! -------- ! This routine calculates the ambient radii for sulfate particles ! with mass of ttn molecules, converts them to count mean radii and ! stores them in the array with address pm6rp. ! It additionally calculates the ambient particle density. ! ! Method: ! ------- ! The calculations of the ambient particle properties are based on ! parameterisations of the mass of sulfate and density derived ! by Julian Wilson from a regression analysis of results of solving ! the generalised Kelvin equation using (F. J. Zeleznik, J. Phys. Chem. ! Ref. Data 20, 1157, 1991), for an H2SO4-H2O mixture, in the ! following parameter ranges: ! 1e2 < pttn < 1E11 [molecules] ! 0.2 < prelhum < 0.9 [1] ! 240 < ptp1 < 330 [K] ! 10000 < papp1 < 100000 [Pa] ! ! Due to the limitations of the parametrisation, the ambient temperature ! is restricted to a minimum of 240 K within this subroutine. ! ! Interface: ! ---------- ! *m7_equiz* is called from *m7* ! ! Externals: ! ---------- ! none ! ! USE mo_aero_m7, ONLY: naermod, nmod, nsol, & ibcks, iocks, issas, ibcas, & iocas, iduas, isscs, ibccs, & ioccs, iducs, & wvb, gmb, avo, wh2so4,& pi, ram2cmr, dh2so4, dh2o ! ! pttn = average mass for single compound in each mode ! [in molec. for sulphate and in ug for bc, oc, ss, and dust] ! pm6rp = count mean radius under ambient conditions [cm] ! pm6dry = count mean radius under dry conditions [cm] ! paernl = aerosol number for each mode [cm-3] ! pww = aerosol water content for each mode [kg(water) m-3(air)] ! zwso4 = percentage by mass of sulfate in a H2O-H2SO4 particle ! containing pttn molecules of sulfate under ambient conditions ! zvso4 = volume of pttn molecules of sulfate [cm3] ! zmso4 = mass of pttn molecules of sulfate [g] ! zdso4h2o = density of sulfate-h2o fraction of a particle with average ! mass [g.cm-3] ! zmso4h2o = mass of sulfate-h2o fraction of a particle with average mass [g] ! zvso4h2o = volume of sulfate-h2o fraction of a particle with average ! mass [cm3] IMPLICIT NONE INTEGER :: kproma, kbdim, klev REAL :: papp1(kbdim,klev), ptp1(kbdim,klev), & prelhum(kbdim,klev) REAL :: pttn(kbdim,klev,naermod), prhop(kbdim,klev,nmod), & pm6dry(kbdim,klev,nsol), pm6rp(kbdim,klev,nmod), & pww(kbdim,klev,nmod), paernl(kbdim,klev,nmod) !--- Local variables: INTEGER :: jk, jl, jmod REAL :: zaerelse, & zwso4, zvso4, zmso4, & zvso4h2o, zmso4h2o, zdso4h2o, & zapp1, ztk, zrh REAL :: ztk2, zln3, zln32, & zlnm, zss2, zlnm2 !CDIR unroll=5 DO 100 jmod=1,nsol DO 90 jk=1,klev DO 80 jl=1,kproma !--- 1) Determine mass of non sulfate compounds in a particle: --------- SELECT CASE (jmod) CASE (1) zaerelse=0. CASE (2) zaerelse = pttn(jl,jk,ibcks)+pttn(jl,jk,iocks) CASE (3) zaerelse = pttn(jl,jk,issas)+pttn(jl,jk,ibcas)+ & pttn(jl,jk,iocas)+pttn(jl,jk,iduas) CASE (4) zaerelse = pttn(jl,jk,isscs)+pttn(jl,jk,ibccs)+ & pttn(jl,jk,ioccs)+pttn(jl,jk,iducs) END SELECT !--- 2) Calculation of the particle properties in the absense of ------- ! other compounds than sulfate: IF (pttn(jl,jk,jmod) > 0.0 .AND. zaerelse < 1.E-15) THEN ! !--- 2.1) Calculation of the ambient particle properties: ----------- ! !--- Constrain ambient temperature to conditions for which the ! parametrisation of the liquid water content works: ! Temperature: ztk = ptp1(jl,jk) ztk = MAX(ztk , 240.) ! Relative Humidity: zrh = prelhum(jl,jk) zrh = MAX(zrh , 0.05) zrh = MIN(zrh , 0.90) !--- Assign auxiliary variables: zapp1=papp1(jl,jk) zlnm = LOG(pttn(jl,jk,jmod)) zlnm2 = zlnm*zlnm zss2 = zrh**2 ztk2 = ztk*ztk zln3 = zlnm/3.0 zln32 = zln3*zln3 ! !--- Percentage by weight of sulfate in the particle [%]: ! (Here we ignore any insoluble mass.) ! zwso4 = wvb(1) + wvb(2)*zlnm + wvb(3)*zrh*zlnm + wvb(4)*ztk*zlnm + & wvb(5)*zrh/ztk + wvb(6)*zlnm2*zrh + wvb(7)*zlnm2*ztk + & wvb(8)*zlnm*zss2 + wvb(9)*zlnm*ztk2 + wvb(10)*zlnm2*zss2 + & wvb(11)*zlnm2*ztk2 + wvb(12)*zss2/ztk2 + wvb(13)*zlnm2 + & wvb(14)*zlnm2*zlnm + wvb(15)*zlnm2*zlnm2 + & wvb(16)*zss2*zrh/(ztk2*ztk) + wvb(17)*LOG(zrh*ztk/zapp1) !--- Dry mass of sulfate in an average particle [g]: zmso4 = pttn(jl,jk,jmod)*wh2so4/avo !--- Dry volume of sulfate in an average particle [cm3]: ! Any temperature or pressure dependency of the ! sulfate density is ingored. zvso4 = zmso4/dh2so4 !--- Mass of sulfate + water in an average particle [g]: zmso4h2o = zmso4/(zwso4/100.0) !--- Density of the sulfate-water fraction of an average particle [g cm-3]: !@@@ Check: changed zwvso4 into zwso4 (now the mass!) zdso4h2o = gmb(1) + gmb(2)*zwso4 + gmb(3)*zln3 + gmb(4)*zrh + & gmb(5)*ztk + gmb(6)*zln32 + gmb(7)*zln3/zrh + & gmb(8)*zln3/ztk + gmb(9)*ztk2 !--- Limits for zdso4h2o: H2O(0.99) and pure H2SO4 (1.841): ! zdso4h2o=MAX(zdso4h2o,dh2o) zdso4h2o=MIN(zdso4h2o,dh2so4) !--- Volume of sulfate-water fraction of an average particle [cm3]: zvso4h2o = zmso4h2o/zdso4h2o !--- 2.2) Calculatiion of the particle radii: ---------------------------- !--- 2.2.1) Dry count mean radius [cm]: pm6dry(jl,jk,jmod)=((zvso4)*0.75/pi)**(1./3.)*ram2cmr(jmod) !--- 2.2.2) Equilibrium wet count mean radius [cm]: pm6rp(jl,jk,jmod) =((zvso4h2o)*0.75/pi)**(1./3.)*ram2cmr(jmod) !--- 2.3) Assignment of the particle density [g cm-3]: ------------------- prhop(jl,jk,jmod)=zdso4h2o !--- 2.4) Store aerosol water for each mode [kg(water) m-3(air)]: pww(jl,jk,jmod)=(zmso4h2o-zmso4)*paernl(jl,jk,jmod)*1.E3 END IF 80 END DO 90 END DO 100 END DO END SUBROUTINE m7_equiz