SUBROUTINE inifis( $ ngrid,nlayer $ ,day_ini,pdaysec,ptimestep $ ,plat,plon,parea $ ,prad,pg,pr,pcpp #ifdef MESOSCALE #include "meso_inc/meso_inc_inifisinvar.F" #endif $ ) ! !======================================================================= ! ! purpose: ! ------- ! ! Initialisation for the physical parametrisations of the LMD ! martian atmospheric general circulation modele. ! ! author: Frederic Hourdin 15 / 10 /93 ! ------- ! modified: Sebastien Lebonnois 11/06/2003 (new callphys.def) ! Ehouarn Millour (oct. 2008) tracers are now identified ! by their names and may not be contiguously ! stored in the q(:,:,:,:) array ! E.M. (june 2009) use getin routine to load parameters ! adapted to the mesoscale use - Aymeric Spiga - 01/2007-07/2011 ! ! ! arguments: ! ---------- ! ! input: ! ------ ! ! ngrid Size of the horizontal grid. ! All internal loops are performed on that grid. ! nlayer Number of vertical layers. ! pdayref Day of reference for the simulation ! pday Number of days counted from the North. Spring ! equinoxe. ! !======================================================================= ! !----------------------------------------------------------------------- ! declarations: ! ------------- ! to use 'getin' USE ioipsl_getincom IMPLICIT NONE #include "dimensions.h" #include "dimphys.h" #include "planete.h" #include "comcstfi.h" #include "comsaison.h" #include "comdiurn.h" #include "comgeomfi.h" #include "callkeys.h" #include "surfdat.h" #include "dimradmars.h" #include "yomaer.h" #include "datafile.h" #include "slope.h" #include "microphys.h" #include "tracer.h" #ifdef MESOSCALE #include "comsoil.h" !!MESOSCALE -- needed to fill volcapa #include "meso_inc/meso_inc_inifisvar.F" #endif REAL prad,pg,pr,pcpp,pdaysec REAL ptimestep INTEGER day_ini INTEGER ngrid,nlayer REAL plat(ngrid),plon(ngrid),parea(ngridmx) INTEGER ig,ierr ! EXTERNAL iniorbit,orbite EXTERNAL SSUM REAL SSUM CHARACTER ch1*12 CHARACTER ch80*80 ! logical chem, h2o ! chem = .false. ! h2o = .false. rad=prad cpp=pcpp g=pg r=pr rcp=r/cpp daysec=pdaysec dtphys=ptimestep #ifdef MESOSCALE #include "meso_inc/meso_inc_inifisini.F" #endif ! -------------------------------------------------------- ! The usual Tests ! -------------- IF (nlayer.NE.nlayermx) THEN PRINT*,'STOP in inifis' PRINT*,'Probleme de dimensions :' PRINT*,'nlayer = ',nlayer PRINT*,'nlayermx = ',nlayermx STOP ENDIF IF (ngrid.NE.ngridmx) THEN PRINT*,'STOP in inifis' PRINT*,'Probleme de dimensions :' PRINT*,'ngrid = ',ngrid PRINT*,'ngridmx = ',ngridmx STOP ENDIF ! -------------------------------------------------------------- ! Reading the "callphys.def" file controlling some key options ! -------------------------------------------------------------- ! check that 'callphys.def' file is around OPEN(99,file='callphys.def',status='old',form='formatted' & ,iostat=ierr) CLOSE(99) IF(ierr.EQ.0) THEN PRINT* PRINT* PRINT*,'--------------------------------------------' PRINT*,' inifis: Parameters for the physics (callphys.def)' PRINT*,'--------------------------------------------' write(*,*) "Directory where external input files are:" datafile="/u/forget/WWW/datagcm/datafile" call getin("datadir",datafile) ! default path write(*,*) " datafile = ",trim(datafile) write(*,*) "Run with or without tracer transport ?" tracer=.false. ! default value call getin("tracer",tracer) write(*,*) " tracer = ",tracer write(*,*) "Diurnal cycle ?" write(*,*) "(if diurnal=False, diurnal averaged solar heating)" diurnal=.true. ! default value call getin("diurnal",diurnal) write(*,*) " diurnal = ",diurnal write(*,*) "Seasonal cycle ?" write(*,*) "(if season=False, Ls stays constant, to value ", & "set in 'start'" season=.true. ! default value call getin("season",season) write(*,*) " season = ",season write(*,*) "Write some extra output to the screen ?" lwrite=.false. ! default value call getin("lwrite",lwrite) write(*,*) " lwrite = ",lwrite write(*,*) "Save statistics in file stats.nc ?" #ifdef MESOSCALE callstats=.false. ! default value #else callstats=.true. ! default value #endif call getin("callstats",callstats) write(*,*) " callstats = ",callstats write(*,*) "Save EOF profiles in file 'profiles' for ", & "Climate Database?" calleofdump=.false. ! default value call getin("calleofdump",calleofdump) write(*,*) " calleofdump = ",calleofdump write(*,*) "Dust scenario: 1=constant dust (read from startfi", & " or set as tauvis); 2=Viking scenario; =3 MGS scenario,", & "=6 cold (low dust) scenario; =7 warm (high dust) scenario ", & "=24,25 ... 30 :Mars Year 24, ... or 30 from TES assimilation" iaervar=3 ! default value call getin("iaervar",iaervar) write(*,*) " iaervar = ",iaervar write(*,*) "Reference (visible) dust opacity at 610 Pa ", & "(matters only if iaervar=1)" ! NB: default value of tauvis is set/read in startfi.nc file call getin("tauvis",tauvis) write(*,*) " tauvis = ",tauvis write(*,*) "Dust vertical distribution:" write(*,*) "(=1 top set by topdustref parameter;", & " =2 Viking scenario; =3 MGS scenario)" iddist=3 ! default value call getin("iddist",iddist) write(*,*) " iddist = ",iddist write(*,*) "Dust top altitude (km). (Matters only if iddist=1)" topdustref= 90.0 ! default value call getin("topdustref",topdustref) write(*,*) " topdustref = ",topdustref write(*,*) "Prescribed surface thermal flux (H/(rho*cp),K m/s)" tke_heat_flux=0. ! default value call getin("tke_heat_flux",tke_heat_flux) write(*,*) " tke_heat_flux = ",tke_heat_flux write(*,*) " 0 means the usual schemes are computing" write(*,*) "call radiative transfer ?" callrad=.true. ! default value call getin("callrad",callrad) write(*,*) " callrad = ",callrad write(*,*) "call slope insolation scheme ?", & "(matters only if callrad=T)" #ifdef MESOSCALE callslope=.true. ! default value #else callslope=.false. ! default value (not supported yet) #endif call getin("callslope",callslope) write(*,*) " callslope = ",callslope write(*,*) "call NLTE radiative schemes ?", & "(matters only if callrad=T)" callnlte=.false. ! default value call getin("callnlte",callnlte) write(*,*) " callnlte = ",callnlte nltemodel=0 !default value write(*,*) "NLTE model?" write(*,*) "0 -> old model, static O" write(*,*) "1 -> old model, dynamic O" write(*,*) "2 -> new model" write(*,*) "(matters only if callnlte=T)" call getin("nltemodel",nltemodel) write(*,*) " nltemodel = ",nltemodel write(*,*) "call CO2 NIR absorption ?", & "(matters only if callrad=T)" callnirco2=.false. ! default value call getin("callnirco2",callnirco2) write(*,*) " callnirco2 = ",callnirco2 write(*,*) "New NIR NLTE correction ?", $ "0-> old model (no correction)", $ "1-> new correction", $ "(matters only if callnirco2=T)" #ifdef MESOSCALE nircorr=0 !default value. this is OK below 60 km. #else nircorr=0 !default value #endif call getin("nircorr",nircorr) write(*,*) " nircorr = ",nircorr write(*,*) "call turbulent vertical diffusion ?" calldifv=.true. ! default value call getin("calldifv",calldifv) write(*,*) " calldifv = ",calldifv write(*,*) "call thermals ?" calltherm=.false. ! default value call getin("calltherm",calltherm) write(*,*) " calltherm = ",calltherm write(*,*) "output thermal diagnostics ?" outptherm=.false. ! default value call getin("outptherm",outptherm) write(*,*) " outptherm = ",outptherm write(*,*) "call convective adjustment ?" calladj=.true. ! default value call getin("calladj",calladj) write(*,*) " calladj = ",calladj if (calltherm .and. (.not. calladj)) then print*,'Convadj has to be activated when using thermals' stop endif write(*,*) "call Richardson-based surface layer ?" callrichsl=.false. ! default value call getin("callrichsl",callrichsl) write(*,*) " callrichsl = ",callrichsl if (calltherm .and. .not.callrichsl) then print*,'WARNING WARNING WARNING' print*,'if calltherm=T we strongly advise that ' print*,'you use the new surface layer scheme ' print*,'by setting callrichsl=T ' endif if (calladj .and. callrichsl .and. (.not. calltherm)) then print*,'You should not be calling the convective adjustment & scheme with the Richardson surface-layer and without the thermals &. This approach is not & physically consistent and can lead to unrealistic friction & values.' print*,'If you want to use the Ri. surface-layer, either & activate thermals OR de-activate the convective adjustment.' stop endif write(*,*) "call CO2 condensation ?" callcond=.true. ! default value call getin("callcond",callcond) write(*,*) " callcond = ",callcond write(*,*)"call thermal conduction in the soil ?" callsoil=.true. ! default value call getin("callsoil",callsoil) write(*,*) " callsoil = ",callsoil write(*,*)"call Lott's gravity wave/subgrid topography ", & "scheme ?" calllott=.true. ! default value call getin("calllott",calllott) write(*,*)" calllott = ",calllott write(*,*)"rad.transfer is computed every iradia", & " physical timestep" iradia=1 ! default value call getin("iradia",iradia) write(*,*)" iradia = ",iradia write(*,*)"Output of the exchange coefficient mattrix ?", & "(for diagnostics only)" callg2d=.false. ! default value call getin("callg2d",callg2d) write(*,*)" callg2d = ",callg2d write(*,*)"Rayleigh scattering : (should be .false. for now)" rayleigh=.false. call getin("rayleigh",rayleigh) write(*,*)" rayleigh = ",rayleigh ! TRACERS: ! dustbin write(*,*)"Transported dust ? (if >0, use 'dustbin' dust bins)" dustbin=0 ! default value call getin("dustbin",dustbin) write(*,*)" dustbin = ",dustbin ! active write(*,*)"Radiatively active dust ? (matters if dustbin>0)" active=.false. ! default value call getin("active",active) write(*,*)" active = ",active ! Test of incompatibility: ! if active is used, then dustbin should be > 0 if (active.and.(dustbin.lt.1)) then print*,'if active is used, then dustbin should > 0' stop endif ! doubleq write(*,*)"use mass and number mixing ratios to predict", & " dust size ?" doubleq=.false. ! default value call getin("doubleq",doubleq) write(*,*)" doubleq = ",doubleq ! submicron submicron=.false. ! default value call getin("submicron",submicron) write(*,*)" submicron = ",submicron ! Test of incompatibility: ! if doubleq is used, then dustbin should be 2 if (doubleq.and.(dustbin.ne.2)) then print*,'if doubleq is used, then dustbin should be 2' stop endif if (doubleq.and.submicron.and.(nqmx.LT.3)) then print*,'If doubleq is used with a submicron tracer,' print*,' then the number of tracers has to be' print*,' larger than 3.' stop endif ! lifting write(*,*)"dust lifted by GCM surface winds ?" lifting=.false. ! default value call getin("lifting",lifting) write(*,*)" lifting = ",lifting ! Test of incompatibility: ! if lifting is used, then dustbin should be > 0 if (lifting.and.(dustbin.lt.1)) then print*,'if lifting is used, then dustbin should > 0' stop endif ! callddevil write(*,*)" dust lifted by dust devils ?" callddevil=.false. !default value call getin("callddevil",callddevil) write(*,*)" callddevil = ",callddevil ! Test of incompatibility: ! if dustdevil is used, then dustbin should be > 0 if (callddevil.and.(dustbin.lt.1)) then print*,'if dustdevil is used, then dustbin should > 0' stop endif ! sedimentation write(*,*) "Gravitationnal sedimentation ?" sedimentation=.true. ! default value call getin("sedimentation",sedimentation) write(*,*) " sedimentation = ",sedimentation ! activice write(*,*) "Radiatively active transported atmospheric ", & "water ice ?" activice=.false. ! default value call getin("activice",activice) write(*,*) " activice = ",activice ! water write(*,*) "Compute water cycle ?" water=.false. ! default value call getin("water",water) write(*,*) " water = ",water ! thermal inertia feedback write(*,*) "Activate the thermal inertia feedback ?" tifeedback=.false. ! default value call getin("tifeedback",tifeedback) write(*,*) " tifeedback = ",tifeedback ! Test of incompatibility: if (tifeedback.and..not.water) then print*,'if tifeedback is used,' print*,'water should be used too' stop endif if (tifeedback.and..not.callsoil) then print*,'if tifeedback is used,' print*,'callsoil should be used too' stop endif if (activice.and..not.water) then print*,'if activice is used, water should be used too' stop endif if (water.and..not.tracer) then print*,'if water is used, tracer should be used too' stop endif ! water ice clouds effective variance distribution for sedimentaion write(*,*) "effective variance for water ice clouds ?" nuice_sed=0.45 call getin("nuice_sed",nuice_sed) write(*,*) "water_param nueff Sedimentation:", nuice_sed ! ccn factor if no scavenging write(*,*) "water param CCN reduc. factor ?", ccn_factor ccn_factor = 4.5 call getin("ccn_factor",ccn_factor) write(*,*)" ccn_factor = ",ccn_factor write(*,*)"Careful: only used when microphys=F, otherwise" write(*,*)"the contact parameter is used instead;" ! microphys write(*,*)"Microphysical scheme for water-ice clouds?" microphys=.false. ! default value call getin("microphys",microphys) write(*,*)" microphys = ",microphys ! microphysical parameter contact write(*,*) "water contact parameter ?" mteta = 0.95 call getin("mteta",mteta) write(*,*) "mteta = ", mteta ! scavenging write(*,*)"Dust scavenging by H2O/CO2 snowfall ?" scavenging=.false. ! default value call getin("scavenging",scavenging) write(*,*)" scavenging = ",scavenging ! Test of incompatibility: ! if scavenging is used, then dustbin should be > 0 if ((microphys.and..not.doubleq).or. & (microphys.and..not.water)) then print*,'if microphys is used, then doubleq,' print*,'and water must be used!' stop endif if (microphys.and..not.scavenging) then print*,'' print*,'----------------WARNING-----------------' print*,'microphys is used without scavenging !!!' print*,'----------------WARNING-----------------' print*,'' endif if ((scavenging.and..not.microphys).or. & (scavenging.and.(dustbin.lt.1))) then print*,'if scavenging is used, then microphys' print*,'must be used!' stop endif ! Test of incompatibility: write(*,*) "Permanent water caps at poles ?", & " .true. is RECOMMENDED" write(*,*) "(with .true., North cap is a source of water ", & "and South pole is a cold trap)" caps=.true. ! default value call getin("caps",caps) write(*,*) " caps = ",caps ! albedo_h2o_ice write(*,*) "water ice albedo ?" albedo_h2o_ice=0.45 call getin("albedo_h2o_ice",albedo_h2o_ice) write(*,*) " albedo_h2o_ice = ",albedo_h2o_ice ! inert_h2o_ice write(*,*) "water ice thermal inertia ?" inert_h2o_ice=2400 ! (J.m^-2.K^-1.s^-1/2) call getin("inert_h2o_ice",inert_h2o_ice) write(*,*) " inert_h2o_ice = ",inert_h2o_ice ! frost_albedo_threshold write(*,*) "frost thickness threshold for albedo ?" frost_albedo_threshold=0.005 ! 5.4 mic (i.e 0.005 kg.m-2) call getin("frost_albedo_threshold", & frost_albedo_threshold) write(*,*) " frost_albedo_threshold = ", & frost_albedo_threshold ! call Titus crocus line -- DEFAULT IS NONE write(*,*) "Titus crocus line ?" tituscap=.false. ! default value call getin("tituscap",tituscap) write(*,*) "tituscap",tituscap write(*,*) "photochemistry: include chemical species" photochem=.false. ! default value call getin("photochem",photochem) write(*,*) " photochem = ",photochem ! THERMOSPHERE write(*,*) "call thermosphere ?" callthermos=.false. ! default value call getin("callthermos",callthermos) write(*,*) " callthermos = ",callthermos write(*,*) " water included without cycle ", & "(only if water=.false.)" thermoswater=.false. ! default value call getin("thermoswater",thermoswater) write(*,*) " thermoswater = ",thermoswater write(*,*) "call thermal conduction ?", & " (only if callthermos=.true.)" callconduct=.false. ! default value call getin("callconduct",callconduct) write(*,*) " callconduct = ",callconduct write(*,*) "call EUV heating ?", & " (only if callthermos=.true.)" calleuv=.false. ! default value call getin("calleuv",calleuv) write(*,*) " calleuv = ",calleuv write(*,*) "call molecular viscosity ?", & " (only if callthermos=.true.)" callmolvis=.false. ! default value call getin("callmolvis",callmolvis) write(*,*) " callmolvis = ",callmolvis write(*,*) "call molecular diffusion ?", & " (only if callthermos=.true.)" callmoldiff=.false. ! default value call getin("callmoldiff",callmoldiff) write(*,*) " callmoldiff = ",callmoldiff write(*,*) "call thermospheric photochemistry ?", & " (only if callthermos=.true.)" thermochem=.false. ! default value call getin("thermochem",thermochem) write(*,*) " thermochem = ",thermochem write(*,*) "Method to include solar variability" write(*,*) "0-> old method (using solarcondate); ", & "1-> variability wit E10.7" solvarmod=1 call getin("solvarmod",solvarmod) write(*,*) " solvarmod = ",solvarmod write(*,*) "date for solar flux calculation:", & " (1985 < date < 2002)", $ " (Only used if solvarmod=0)" write(*,*) "(Solar min=1996.4 ave=1993.4 max=1990.6)" solarcondate=1993.4 ! default value call getin("solarcondate",solarcondate) write(*,*) " solarcondate = ",solarcondate write(*,*) "Solar variability as observed for MY: " write(*,*) "Only if solvarmod=1" solvaryear=24 call getin("solvaryear",solvaryear) write(*,*) " solvaryear = ",solvaryear write(*,*) "UV heating efficiency:", & "measured values between 0.19 and 0.23 (Fox et al. 1996)", & "lower values may be used to compensate low 15 um cooling" euveff=0.21 !default value call getin("euveff",euveff) write(*,*) " euveff = ", euveff if (.not.callthermos) then if (thermoswater) then print*,'if thermoswater is set, callthermos must be true' stop endif if (callconduct) then print*,'if callconduct is set, callthermos must be true' stop endif if (calleuv) then print*,'if calleuv is set, callthermos must be true' stop endif if (callmolvis) then print*,'if callmolvis is set, callthermos must be true' stop endif if (callmoldiff) then print*,'if callmoldiff is set, callthermos must be true' stop endif if (thermochem) then print*,'if thermochem is set, callthermos must be true' stop endif endif ! Test of incompatibility: ! if photochem is used, then water should be used too if (photochem.and..not.water) then print*,'if photochem is used, water should be used too' stop endif ! if callthermos is used, then thermoswater should be used too ! (if water not used already) if (callthermos .and. .not.water) then if (callthermos .and. .not.thermoswater) then print*,'if callthermos is used, water or thermoswater & should be used too' stop endif endif PRINT*,'--------------------------------------------' PRINT* PRINT* ELSE write(*,*) write(*,*) 'Cannot read file callphys.def. Is it here ?' stop ENDIF 8000 FORMAT(t5,a12,l8) 8001 FORMAT(t5,a12,i8) PRINT* PRINT*,'inifis: daysec',daysec PRINT* PRINT*,'inifis: The radiative transfer is computed:' PRINT*,' each ',iradia,' physical time-step' PRINT*,' or each ',iradia*dtphys,' seconds' PRINT* ! -------------------------------------------------------------- ! Managing the Longwave radiative transfer ! -------------------------------------------------------------- ! In most cases, the run just use the following values : ! ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ callemis=.true. ! ilwd=10*int(daysec/dtphys) ! bug before 22/10/01 ilwd=1 ilwn=1 !2 ilwb=1 !2 linear=.true. ncouche=3 alphan=0.4 semi=0 ! BUT people working hard on the LW may want to read them in 'radia.def' ! ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ OPEN(99,file='radia.def',status='old',form='formatted' . ,iostat=ierr) IF(ierr.EQ.0) THEN write(*,*) 'inifis: Reading radia.def !!!' READ(99,fmt='(a)') ch1 READ(99,*) callemis WRITE(*,8000) ch1,callemis READ(99,fmt='(a)') ch1 READ(99,*) iradia WRITE(*,8001) ch1,iradia READ(99,fmt='(a)') ch1 READ(99,*) ilwd WRITE(*,8001) ch1,ilwd READ(99,fmt='(a)') ch1 READ(99,*) ilwn WRITE(*,8001) ch1,ilwn READ(99,fmt='(a)') ch1 READ(99,*) linear WRITE(*,8000) ch1,linear READ(99,fmt='(a)') ch1 READ(99,*) ncouche WRITE(*,8001) ch1,ncouche READ(99,fmt='(a)') ch1 READ(99,*) alphan WRITE(*,*) ch1,alphan READ(99,fmt='(a)') ch1 READ(99,*) ilwb WRITE(*,8001) ch1,ilwb READ(99,fmt='(a)') ch1 READ(99,'(l1)') callg2d WRITE(*,8000) ch1,callg2d READ(99,fmt='(a)') ch1 READ(99,*) semi WRITE(*,*) ch1,semi end if CLOSE(99) !----------------------------------------------------------------------- ! Some more initialization: ! ------------------------ ! in 'comgeomfi.h' CALL SCOPY(ngrid,plon,1,long,1) CALL SCOPY(ngrid,plat,1,lati,1) CALL SCOPY(ngrid,parea,1,area,1) totarea=SSUM(ngridmx,area,1) ! in 'comdiurn.h' DO ig=1,ngrid sinlat(ig)=sin(plat(ig)) coslat(ig)=cos(plat(ig)) sinlon(ig)=sin(plon(ig)) coslon(ig)=cos(plon(ig)) ENDDO pi=2.*asin(1.) ! NB: pi is a common in comcstfi.h ! managing the tracers, and tests: ! ------------------------------- ! Ehouarn: removed; as these tests are now done in initracer.F ! if(tracer) then ! !! when photochem is used, nqchem_min is the rank !! of the first chemical species ! !! Ehouarn: nqchem_min is now meaningless and no longer used !! nqchem_min = 1 ! if (photochem .or. callthermos) then ! chem = .true. ! end if ! ! if (water .or. thermoswater) h2o = .true. ! !! TESTS ! ! print*,'inifis: TRACERS:' ! write(*,*) " chem=",chem," h2o=",h2o !! write(*,*) " doubleq=",doubleq !! write(*,*) " dustbin=",dustbin ! ! if ((doubleq).and.(h2o).and. ! $ (chem)) then ! print*,' 2 dust tracers (doubleq)' ! print*,' 1 water vapour tracer' ! print*,' 1 water ice tracer' ! print*,nqmx-4,' chemistry tracers' ! endif ! ! if ((doubleq).and.(h2o).and. ! $ .not.(chem)) then ! print*,' 2 dust tracers (doubleq)' ! print*,' 1 water vapour tracer' ! print*,' 1 water ice tracer' ! if (nqmx.LT.4) then ! print*,'nqmx should be at least equal to' ! print*,'4 with these options.' ! stop ! endif ! endif ! ! if (.not.(doubleq).and.(h2o).and. ! $ (chem)) then ! if (dustbin.gt.0) then ! print*,dustbin,' dust bins' ! endif ! print*,nqmx-2-dustbin,' chemistry tracers' ! print*,' 1 water vapour tracer' ! print*,' 1 water ice tracer' ! endif ! ! if (.not.(doubleq).and.(h2o).and. ! $ .not.(chem)) then ! if (dustbin.gt.0) then ! print*,dustbin,' dust bins' ! endif ! print*,' 1 water vapour tracer' ! print*,' 1 water ice tracer' ! if (nqmx.gt.(dustbin+2)) then ! print*,'nqmx should be ',(dustbin+2), ! $ ' with these options...' ! print*,'(or check callphys.def)' ! endif ! if (nqmx.lt.(dustbin+2)) then ! write(*,*) "inifis: nqmx.lt.(dustbin+2)" ! stop ! endif ! endif ! ! endif ! of if (tracer) ! ! RETURN END