r5152 | xinzhang | 2011-09-26 21:04:33 -0700 (Mon, 26 Sep 2011) | 3 lines
[wrffire.git] / wrfv2_fire / phys / module_mp_sbu_ylin.F
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1 !WRF:MODEL_LAYER:PHYSICS
3 !--- The code is based on Lin and Colle (A New Bulk Microphysical Scheme 
4 !             that Includes Riming Intensity and Temperature Dependent Ice Characteristics, 2011, MWR)
5 !             and Lin et al. (Parameterization of riming intensity and its impact on ice fall speed using ARM data, 2011, MWR)
6 !--- NOTE: 1) Prognose variables are: qi,PI(precipitating ice, qs, which includes snow, partially rimed snow and graupel),qw,qr
7 !---       2) Sedimentation flux is based on Prudue Lin scheme 
8 !---       2) PI has varying properties depending on riming intensity (Ri, diagnosed currently following Lin et al. (2011, MWR) and T 
9 !---       3) Autoconverion is based on Liu and Daum (2004)         
10 !---       4) PI size distribution assuming Gamma distribution, but mu_s=0 (Exponential) currently
11 !---       5) No density dependent fall speed since the V-D is derived using Best number approach, which already includes density effect 
12 !---       6) Future work will include radar equivalent reflectivity using the new PI property (A-D, M-D, N(D)). If you use RIP for reflectivity 
13 !---          computation, please note that snow is (1-Ri)*qs and graupel is Ri*qs. Otherwise, reflectivity will be underestimated.      
14 !---       7) The Liu and Daum autoconverion is quite sensitive on Nt_c. For mixed-phase cloud and marine environment, Nt_c of 10 or 20 is suggested.
15 !---          default value is 10E.6. Change accordingly for your use.
18       MODULE module_mp_sbu_ylin
19       USE    module_wrf_error
21 !..Parameters user might change based on their need
22       REAL, PARAMETER, PRIVATE :: RH = 1.0
23       REAL, PARAMETER, PRIVATE :: xnor = 8.0e6
24       REAL, PARAMETER, PRIVATE :: Nt_c = 10.E6
25 !..Water vapor and air gas constants at constant pressure
26       REAL, PARAMETER, PRIVATE :: Rvapor = 461.5
27       REAL, PARAMETER, PRIVATE :: oRv    = 1./Rvapor
28       REAL, PARAMETER, PRIVATE :: Rair   = 287.04
29       REAL, PARAMETER, PRIVATE :: Cp     = 1004.0
30       REAL, PARAMETER, PRIVATE :: grav   = 9.81
31       REAL, PARAMETER, PRIVATE :: rhowater = 1000.0
32       REAL, PARAMETER, PRIVATE :: rhosnow  = 100.0
34       REAL, PARAMETER, PRIVATE :: SVP1=0.6112
35       REAL, PARAMETER, PRIVATE :: SVP2=17.67
36       REAL, PARAMETER, PRIVATE :: SVP3=29.65
37       REAL, PARAMETER, PRIVATE :: SVPT0=273.15
38       REAL, PARAMETER, PRIVATE :: EP1=Rvapor/Rair-1.
39       REAL, PARAMETER, PRIVATE :: EP2=Rair/Rvapor
40 !..Enthalpy of sublimation, vaporization, and fusion at 0C.
41       REAL, PARAMETER, PRIVATE :: XLS = 2.834E6
42       REAL, PARAMETER, PRIVATE :: XLV = 2.5E6
43       REAL, PARAMETER, PRIVATE :: XLF = XLS - XLV
46       REAL, PARAMETER, PRIVATE ::                           &
47              qi0 = 1.0e-3,                                  &   !--- ice aggregation to snow threshold
48              xmi50 = 4.8e-10, xmi40 = 2.46e-10,             &
49              xni0 = 1.0e-2, xmnin = 1.05e-18, bni = 0.5,    &
50              di50 = 1.0e-4, xmi = 4.19e-13,                 &   !--- parameters used in BF process
51              bv_r = 0.8, bv_i = 0.25,                       &
52              o6 = 1./6.,  cdrag = 0.6,                      &
53              avisc = 1.49628e-6, adiffwv = 8.7602e-5,       &
54              axka = 1.4132e3, cw = 4.187e3,  ci = 2.093e3
55 CONTAINS
57 !-------------------------------------------------------------------
58 !  Lin et al., 1983, JAM, 1065-1092, and
59 !  Rutledge and Hobbs, 1984, JAS, 2949-2972
60 !-------------------------------------------------------------------
61       SUBROUTINE sbu_ylin(th                                       &
62                       ,qv, ql, qr                                  &
63                       ,qi, qs, Ri3D                                &
64                       ,rho, pii, p                                 &
65                       ,dt_in                                       &
66                       ,z,ht, dz8w                                  &
67                       ,RAINNC, RAINNCV                             &
68                       ,ids,ide, jds,jde, kds,kde                   &
69                       ,ims,ime, jms,jme, kms,kme                   &
70                       ,its,ite, jts,jte, kts,kte                   &
71                                                                    )
72 !-------------------------------------------------------------------
73       IMPLICIT NONE
74 !-------------------------------------------------------------------
77      INTEGER,   INTENT(IN   )    ::   ids,ide, jds,jde, kds,kde , &
78                                       ims,ime, jms,jme, kms,kme , &
79                                       its,ite, jts,jte, kts,kte
81      REAL, DIMENSION( ims:ime , kms:kme , jms:jme ),              &
82         INTENT(INOUT) ::                                          &
83                                                               th, &
84                                                               qv, &
85                                                            qi,ql, &
86                                                            qs,qr
88 ! YLIN
89 ! Adding RI3D as a variable to the interface
90      REAL, DIMENSION( ims:ime, kms:kme, jms:jme ),                &
91         INTENT(INOUT) :: Ri3D
95      REAL, DIMENSION( ims:ime , kms:kme , jms:jme ),              &
96         INTENT(IN   ) ::                                          &
97                                                              rho, &
98                                                              pii, &
99                                                              z,p, &
100                                                             dz8w
103      REAL , DIMENSION( ims:ime , jms:jme ) , INTENT(IN) ::       ht
104      REAL, INTENT(IN   ) ::                                   dt_in  
106      REAL, DIMENSION( ims:ime , jms:jme ),                           &
107         INTENT(INOUT) ::                                  RAINNC, &
108                                                           RAINNCV
110 ! LOCAL VAR
112      INTEGER             ::                            min_q, max_q
114      REAL, DIMENSION( its:ite , jts:jte )                            &
115                                ::        rain, snow,ice
117      REAL, DIMENSION( kts:kte )   ::                  qvz, qlz, qrz, &
118                                                       qiz, qsz, qgz, &
119                                                                 thz, &
120                                                         tothz, rhoz, &
121                                                       orhoz, sqrhoz, &
122                                                            prez, zz, &
123                                                         dzw
125 ! Added vertical profile of Ri (riz) as a variable
126      REAL, DIMENSION( kts:kte ) :: riz
129      REAL    ::         dt, pptice, pptrain, pptsnow, pptgraul, rhoe_s
131      INTEGER ::               i,j,k
133       dt=dt_in
134       rhoe_s=1.29
135   
136       j_loop:  DO j = jts, jte
137       i_loop:  DO i = its, ite
139 !- write data from 3-D to 1-D
141       DO k = kts, kte
142        qvz(k)=qv(i,k,j)
143        qlz(k)=ql(i,k,j)
144        qrz(k)=qr(i,k,j)
145        qiz(k)=qi(i,k,j)
146        qsz(k)=qs(i,k,j)
147        thz(k)=th(i,k,j)
148        rhoz(k)=rho(i,k,j)
149        orhoz(k)=1./rhoz(k)
150        prez(k)=p(i,k,j)
151 !       sqrhoz(k)=sqrt(rhoe_s*orhoz(k))
152 ! no density dependence of fall speed as Note #5, you can turn it on to increase fall speed at low pressure.
153        sqrhoz(k)=1.0
154        tothz(k)=pii(i,k,j)
155        zz(k)=z(i,k,j)
156        dzw(k)=dz8w(i,k,j)
157       END DO
159       pptrain=0.
160       pptsnow=0.
161       pptice =0.
163 !     CALL wrf_debug ( 100 , 'microphysics_driver: calling clphy1d_ylin' )
165      CALL clphy1d_ylin(  dt, qvz, qlz, qrz, qiz, qsz,              &
166                          thz, tothz, rhoz, orhoz, sqrhoz,          &
167                          prez, zz, dzw, ht(I,J),                   &
168                          pptrain, pptsnow, pptice,                 &
169                          kts, kte, i, j, riz                       )
172 ! Precipitation from cloud microphysics -- only for one time step
174 ! unit is transferred from m to mm
176       rain(i,j)= pptrain
177       snow(i,j)= pptsnow
178       ice(i,j) = pptice
180       RAINNCV(i,j)= pptrain + pptsnow + pptice
181       RAINNC(i,j) = RAINNC(i,j) + pptrain + pptsnow + pptice
184 !- update data from 1-D back to 3-D
186       DO k = kts, kte
187        qv(i,k,j)=qvz(k)
188        ql(i,k,j)=qlz(k)
189        qr(i,k,j)=qrz(k)
190        th(i,k,j)=thz(k)
191        qi(i,k,j)=qiz(k)
192        qs(i,k,j)=qsz(k)
193        ri3d(i,k,j)=riz(k)
194       END DO
196       ENDDO i_loop
197       ENDDO j_loop
199       END SUBROUTINE sbu_ylin
202 !-----------------------------------------------------------------------
203       SUBROUTINE clphy1d_ylin(dt, qvz, qlz, qrz, qiz, qsz,             &
204                       thz, tothz, rho, orho, sqrho,                    &
205                       prez, zz, dzw, zsfc, pptrain, pptsnow,pptice,    &
206                       kts, kte, i, j,riz                               )
207 !-----------------------------------------------------------------------
208       IMPLICIT NONE
209 !-----------------------------------------------------------------------
210 !  This program handles the vertical 1-D cloud micphysics
211 !-----------------------------------------------------------------------
212 ! avisc: constant in empirical formular for dynamic viscosity of air
213 !         =1.49628e-6 [kg/m/s] = 1.49628e-5 [g/cm/s]
214 ! adiffwv: constant in empirical formular for diffusivity of water
215 !          vapor in air
216 !          = 8.7602e-5 [kgm/s3] = 8.7602 [gcm/s3]
217 ! axka: constant in empirical formular for thermal conductivity of air
218 !       = 1.4132e3 [m2/s2/K] = 1.4132e7 [cm2/s2/K]
219 ! qi0: mixing ratio threshold for cloud ice aggregation [kg/kg]
220 ! xmi50: mass of a 50 micron ice crystal
221 !        = 4.8e-10 [kg] =4.8e-7 [g]
222 ! xmi40: mass of a 40 micron ice crystal
223 !        = 2.46e-10 [kg] = 2.46e-7 [g]
224 ! di50: diameter of a 50 micro (radius) ice crystal
225 !       =1.0e-4 [m]
226 ! xmi: mass of one cloud ice crystal
227 !      =4.19e-13 [kg] = 4.19e-10 [g]
228 ! oxmi=1.0/xmi
230 ! xni0=1.0e-2 [m-3] The value given in Lin et al. is wrong.(see
231 !                   Hsie et al.(1980) and Rutledge and Hobbs(1983) )
232 ! bni=0.5 [K-1]
233 ! xmnin: mass of a natural ice nucleus
234 !    = 1.05e-18 [kg] = 1.05e-15 [g] This values is suggested by
235 !                    Hsie et al. (1980)
236 !    = 1.0e-12 [kg] suggested by Rutlegde and Hobbs (1983)
238 ! av_r: av_r in empirical formular for terminal
239 !         velocity of raindrop
240 !         =2115.0 [cm**(1-b)/s] = 2115.0*0.01**(1-b) [m**(1-b)/s]
241 ! bv_r: bv_r in empirical formular for terminal
242 !         velocity of raindrop
243 !         =0.8
244 ! av_i: av_i in empirical formular for terminal
245 !         velocity of snow
246 !         =152.93 [cm**(1-d)/s] = 152.93*0.01**(1-d) [m**(1-d)/s]
247 ! bv_i: bv_i in empirical formular for terminal
248 !         velocity of snow
249 !         =0.25
250 ! vf1r: ventilation factors for rain =0.78
251 ! vf2r: ventilation factors for rain =0.31
252 ! vf1s: ventilation factors for snow =0.65
253 ! vf2s: ventilation factors for snow =0.44
255 !----------------------------------------------------------------------
257      INTEGER, INTENT(IN   )               :: kts, kte, i, j
259      REAL,    DIMENSION( kts:kte ),                                   &
260            INTENT(INOUT)               :: qvz, qlz, qrz, qiz, qsz,    &
261                                           thz
263      REAL,    DIMENSION( kts:kte ),                                   &
264            INTENT(IN   )               :: tothz, rho, orho, sqrho,    &
265                                           prez, zz, dzw
268      REAL,    INTENT(INOUT)               :: pptrain, pptsnow, pptice
270      REAL,    INTENT(IN   )               :: dt, zsfc
272 ! local vars
274      REAL                                :: obp4, bp3, bp5, bp6, odp4,  &
275                                             dp3, dp5, dp5o2
277 ! temperary vars
279      REAL                              :: tmp, tmp0, tmp1, tmp2,tmp3,  &
280                                           tmp4, tmpa,tmpb,tmpc,tmpd,alpha1,  &
281                                           qic, abi,abr, abg, odtberg,  &
282                                           vti50,eiw,eri,esi,esr, esw,  &
283                                           erw,delrs,term0,term1,       &
284                                           Ap, Bp,                      &
285                                           factor, tmp_r, tmp_s,tmp_g,  &
286                                           qlpqi, rsat, a1, a2, xnin
289      REAL, DIMENSION( kts:kte )    ::  oprez, tem, temcc, theiz, qswz,    &
290                                        qsiz, qvoqswz, qvoqsiz, qvzodt,    &
291                                        qlzodt, qizodt, qszodt, qrzodt
293 !--- microphysical processes
295      REAL, DIMENSION( kts:kte )    :: psnow, psaut, psfw,  psfi,  praci,  &
296                                       piacr, psaci, psacw, psdep, pssub,  &
297                                       pracs, psacr, psmlt, psmltevp,      &
298                                       prain, praut, pracw, prevp, pvapor, &
299                                       pclw,  pladj, pcli,  pimlt, pihom,  &
300                                       pidw,  piadj, pgfr,                 &
301                                       qschg
304      REAL, DIMENSION( kts:kte )    :: qvsbar, rs0, viscmu, visc, diffwv,  &
305                                       schmidt, xka
306 !---- new snow parameters
308      REAL, DIMENSION( kts:kte ):: ab_s,ab_r,ab_riming,lamc 
309      REAL, DIMENSION( kts:kte ):: cap_s       !---- capacitance of snow
311      REAL, PARAMETER :: vf1s = 0.65, vf2s = 0.44, vf1r =0.78 , vf2r = 0.31 
313      REAL, PARAMETER :: am_c1=0.004, am_c2= 6e-5,    am_c3=0.15
314      REAL, PARAMETER :: bm_c1=1.85,  bm_c2= 0.003,   bm_c3=1.25
315      REAL, PARAMETER :: aa_c1=1.28,  aa_c2= -0.012,  aa_c3=-0.6
316      REAL, PARAMETER :: ba_c1=1.5,   ba_c2= 0.0075,  ba_c3=0.5
318      REAL, PARAMETER :: best_a=1.08 ,  best_b = 0.499
319      REAL, DIMENSION(kts:kte):: am_s,bm_s,av_s,bv_s,Ri,N0_s,tmp_ss,lams  
320      REAL, DIMENSION(kts:kte):: aa_s,ba_s,tmp_sa  
321      REAL, PARAMETER :: mu_s=0.,mu_i=0.,mu_r=0.
323      REAL :: tc0, disp, Dc_liu, eta, mu_c, R6c      !--- for Liu's autoconversion
325 ! Adding variable Riz, which will duplicate Ri but be a copy passed upward
327      REAL, DIMENSION(kts:kte) :: Riz
329      REAL, DIMENSION( kts:kte )    :: vtr, vts,                   &
330                                       vtrold, vtsold, vtiold,     &
331                                       xlambdar, xlambdas,            &
332                                       olambdar, olambdas
334      REAL                          :: episp0k, dtb, odtb, pi, pio4,       &
335                                       pio6, oxLf, xLvocp, xLfocp, av_r,   &
336                                       av_i, ocdrag, gambp4, gamdp4,       &
337                                       gam4pt5, Cpor, oxmi, gambp3, gamdp3,&
338                                       gambp6, gam3pt5, gam2pt75, gambp5o2,&
339                                       gamdp5o2, cwoxlf, ocp, xni50, es
341      REAL                          :: qvmin=1.e-20
342      REAL                          :: temc1,save1,save2,xni50mx
344 ! for terminal velocity flux
346      INTEGER                       :: min_q, max_q, max_ri_k, k
347      REAL                          :: max_ri
348      REAL                          :: t_del_tv, del_tv, flux, fluxin, fluxout ,tmpqrz
349      LOGICAL                       :: notlast
351       mu_c = AMIN1(15., (1000.E6/Nt_c + 2.))
352       R6c  = 10.0E-6      !---- 10 micron, threshold radius of cloud droplet
353       dtb=dt
354       odtb=1./dtb
355       pi  =acos(-1.)
356       pio4=acos(-1.)/4.
357       pio6=acos(-1.)/6.
358       ocp=1./cp
359       oxLf=1./xLf
360       xLvocp=xLv/cp
361       xLfocp=xLf/cp
362       Cpor=cp/Rair
363       oxmi=1.0/xmi
364       cwoxlf=cw/xlf 
365       av_r=2115.0*0.01**(1-bv_r)
366       av_i=152.93*0.01**(1-bv_i)
367       ocdrag=1./Cdrag
368       episp0k=RH*ep2*1000.*svp1
370       gambp4=ggamma(bv_r+4.)
371       gamdp4=ggamma(bv_i+4.)
372       gambp3=ggamma(bv_r+3.)
373       gambp6=ggamma(bv_r+6)
374       gambp5o2=ggamma((bv_r+5.)/2.)
375       gamdp5o2=ggamma((bv_i+5.)/2.)
377 !     oprez       1./prez ( prez : pressure)
378 !     qsw         saturated mixing ratio on water surface
379 !     qsi         saturated mixing ratio on ice surface
380 !     episp0k     RH*e*saturated pressure at 273.15 K  = 611.2 hPa (Rogers and Yau 1989)
381 !     qvoqsw      qv/qsw
382 !     qvoqsi      qv/qsi
383 !     qvzodt      qv/dt
384 !     qlzodt      ql/dt
385 !     qizodt      qi/dt
386 !     qszodt      qs/dt
387 !     qrzodt      qr/dt
388 !     temcc       temperature in dregee C
391       obp4=1.0/(bv_r+4.0)
392       bp3=bv_r+3.0
393       bp5=bv_r+5.0
394       bp6=bv_r+6.0
395       odp4=1.0/(bv_i+4.0)
396       dp3=bv_i+3.0
397       dp5=bv_i+5.0
398       dp5o2=0.5*(bv_i+5.0)
400       do k=kts,kte
401          oprez(k)=1./prez(k)
402          qlz(k)=amax1( 0.0,qlz(k) )
403          qiz(k)=amax1( 0.0,qiz(k) )
404          qvz(k)=amax1( qvmin,qvz(k) )
405          qsz(k)=amax1( 0.0,qsz(k) )
406          qrz(k)=amax1( 0.0,qrz(k) )
407          tem(k)=thz(k)*tothz(k)
408          temcc(k)=tem(k)-273.15
409          es=1000.*svp1*exp( svp2*temcc(k)/(tem(k)-svp3) )  !--- RY89 Eq(2.17)
410          qswz(k)=ep2*es/(prez(k)-es)
411          if (tem(k) .lt. 273.15 ) then
412             es=1000.*svp1*exp( 21.8745584*(tem(k)-273.16)/(tem(k)-7.66) )
413             qsiz(k)=ep2*es/(prez(k)-es)
414             if (temcc(k) .lt. -40.0) qswz(k)=qsiz(k)
415          else
416             qsiz(k)=qswz(k)
417          endif
419          qvoqswz(k)=qvz(k)/qswz(k)
420          qvoqsiz(k)=qvz(k)/qsiz(k)
421          qvzodt(k)=amax1( 0.0,odtb*qvz(k) )
422          qlzodt(k)=amax1( 0.0,odtb*qlz(k) )
423          qizodt(k)=amax1( 0.0,odtb*qiz(k) )
424          qszodt(k)=amax1( 0.0,odtb*qsz(k) )
425          qrzodt(k)=amax1( 0.0,odtb*qrz(k) )
426          theiz(k)=thz(k)+(xlvocp*qvz(k)-xlfocp*qiz(k))/tothz(k)
427       enddo
429       do k=kts,kte
431          psnow(k)=0.0
432          psaut(k)=0.0
433          psfw(k)=0.0
434          psfi(k)=0.0
435          praci(k)=0.0
436          piacr(k)=0.0
437          psaci(k)=0.0
438          psacw(k)=0.0
439          psdep(k)=0.0
440          pssub(k)=0.0
441          pracs(k)=0.0
442          psacr(k)=0.0
443          psmlt(k)=0.0
444          psmltevp(k)=0.0
446          prain(k)=0.0
447          praut(k)=0.0
448          pracw(k)=0.0
449          prevp(k)=0.0
450          pgfr(k)=0.0
452          pvapor(k)=0.0
454          pclw(k)=0.0
455          pladj(k)=0.0
457          pcli(k)=0.0
458          pimlt(k)=0.0
459          pihom(k)=0.0
460          pidw(k)=0.0
461          piadj(k)=0.0
463          qschg(k)=0.
465       enddo
467 !***********************************************************************
468 !*****  compute viscosity,difusivity,thermal conductivity, and    ******
469 !*****  Schmidt number                                            ******
470 !***********************************************************************
471 !c------------------------------------------------------------------
472 !c      viscmu: dynamic viscosity of air kg/m/s
473 !c      visc: kinematic viscosity of air = viscmu/rho (m2/s)
474 !c      avisc=1.49628e-6 kg/m/s=1.49628e-5 g/cm/s
475 !c      viscmu=1.718e-5 kg/m/s in RH
476 !c      diffwv: Diffusivity of water vapor in air
477 !c      adiffwv = 8.7602e-5 (8.794e-5 in MM5) kgm/s3
478 !c              = 8.7602 (8.794 in MM5) gcm/s3
479 !c      diffwv(k)=2.26e-5 m2/s
480 !c      schmidt: Schmidt number=visc/diffwv
481 !c      xka: thermal conductivity of air J/m/s/K (Kgm/s3/K)
482 !c      xka(k)=2.43e-2 J/m/s/K in RH
483 !c      axka=1.4132e3 (1.414e3 in MM5) m2/s2/k = 1.4132e7 cm2/s2/k
484 !c------------------------------------------------------------------
485       DO k=kts,kte
486         viscmu(k)=avisc*tem(k)**1.5/(tem(k)+120.0)
487         visc(k)=viscmu(k)*orho(k)
488         diffwv(k)=adiffwv*tem(k)**1.81*oprez(k)
489         schmidt(k)=visc(k)/diffwv(k)
490         xka(k)=axka*viscmu(k)
491         rs0(k)=ep2*1000.*svp1/(prez(k)-1000.*svp1)
492       END DO
494 ! ---- YLIN, set snow variables
496 !---- A+B in depositional growth, the first try just take from Rogers and Yau(1989)
497 !         ab_s(k) = lsub*lsub*orv/(tcond(k)*temp(k))+&
498 !                   rv*temp(k)/(diffu(k)*qvsi(k))
500        do k = kts, kte
501          tc0   = tem(k)-273.15       
502         if (rho(k)*qlz(k) .gt. 1e-5 .AND. rho(k)*qsz(k) .gt. 1e-5) then 
503          Ri(k) = 1.0/(1.0+6e-5/(rho(k)**1.170*qlz(k)*qsz(k)**0.170))
504         else
505          Ri(k) = 0
506         endif
507        enddo
509 !--- make sure Ri does not decrease downward in a column
511        max_ri_k = MAXLOC(Ri,dim=1)
512        max_ri   = MAXVAL(Ri)
514        do k = kts, max_ri_k
515          Ri(k) = max_ri
516        enddo
518 !--- YLIN, get PI properties
519       do k = kts, kte
520          Ri(k) = AMAX1(0.,AMIN1(Ri(k),1.0))      
521 ! Store the value of Ri(k) as Riz(k)
522          Riz(k) = Ri(k)
524          cap_s(k)= 0.25*(1+Ri(k))
525          tc0     = AMIN1(-0.1, tem(k)-273.15)          
526          N0_s(k) = amin1(2.0E8, 2.0E6*exp(-0.12*tc0))          
527          am_s(k) = am_c1+am_c2*tc0+am_c3*Ri(k)*Ri(k)   !--- Heymsfield 2007
528          am_s(k) = AMAX1(0.000023,am_s(k))             !--- use the a_min in table 1 of Heymsfield
529          bm_s(k) = bm_c1+bm_c2*tc0+bm_c3*Ri(k)
530          bm_s(k) = AMIN1(bm_s(k),3.0)                  !---- capped by 3
531 !---  converting from cgs to SI unit
532          am_s(k) =  10**(2*bm_s(k)-3.0)*am_s(k)
533          aa_s(k) = aa_c1 + aa_c2*tc0 + aa_c3*Ri(k)
534          ba_s(k) = ba_c1 + ba_c2*tc0 + ba_c3*Ri(k)
535 !---  convert to SI unit as in paper
536          aa_s(k) = (1e-2)**(2.0-ba_s(k))*aa_s(k)
537 !---- get v from Mitchell 1996
538          av_s(k) = best_a*viscmu(k)*(2*grav*am_s(k)/rho(k)/aa_s(k)/(viscmu(k)**2))**best_b
539          bv_s(k) = best_b*(bm_s(k)-ba_s(k)+2)-1
540         
541          tmp_ss(k)= bm_s(k)+mu_s+1
542          tmp_sa(k)= ba_s(k)+mu_s+1
544       enddo 
547 !***********************************************************************
548 ! Calculate precipitation fluxes due to terminal velocities.
549 !***********************************************************************
551 !- Calculate termianl velocity (vt?)  of precipitation q?z
552 !- Find maximum vt? to determine the small delta t
554 !-- rain
556 !       CALL wrf_debug ( 100 , 'module_ylin, start precip fluxes' )
558       t_del_tv=0.
559       del_tv=dtb
560       notlast=.true.
562       DO while (notlast)
564        min_q=kte
565        max_q=kts-1
567       do k=kts,kte-1
568          if (qrz(k) .gt. 1.0e-8) then
569             min_q=min0(min_q,k)
570             max_q=max0(max_q,k)
571             tmp1=sqrt(pi*rhowater*xnor/rho(k)/qrz(k))
572             tmp1=sqrt(tmp1)
573             vtrold(k)=o6*av_r*gambp4*sqrho(k)/tmp1**bv_r
574             if (k .eq. 1) then
575                del_tv=amin1(del_tv,0.9*(zz(k)-zsfc)/vtrold(k))
576             else
577                del_tv=amin1(del_tv,0.9*(zz(k)-zz(k-1))/vtrold(k))
578             endif
579          else
580             vtrold(k)=0.
581          endif
582       enddo
584       if (max_q .ge. min_q) then
586 !- Check if the summation of the small delta t >=  big delta t
587 !             (t_del_tv)          (del_tv)             (dtb)
589          t_del_tv=t_del_tv+del_tv
591          if ( t_del_tv .ge. dtb ) then
592               notlast=.false.
593               del_tv=dtb+del_tv-t_del_tv
594          endif
596          fluxin=0.
597          do k=max_q,min_q,-1
598             fluxout=rho(k)*vtrold(k)*qrz(k)
599             flux=(fluxin-fluxout)/rho(k)/dzw(k)
600             tmpqrz=qrz(k)
601             qrz(k)=qrz(k)+del_tv*flux
602             fluxin=fluxout
603          enddo
604          if (min_q .eq. 1) then
605             pptrain=pptrain+fluxin*del_tv
606          else
607             qrz(min_q-1)=qrz(min_q-1)+del_tv*  &
608                           fluxin/rho(min_q-1)/dzw(min_q-1)
609          endif
611       else
612          notlast=.false.
613       endif
614       ENDDO
617 !-- snow
619       t_del_tv=0.
620       del_tv=dtb
621       notlast=.true.
623       DO while (notlast)
625        min_q=kte
626        max_q=kts-1
628       do k=kts,kte-1
629          if (qsz(k) .gt. 1.0e-8) then
630             min_q=min0(min_q,k)
631             max_q=max0(max_q,k)
633             tmp1= (am_s(k)*N0_s(k)*ggamma(tmp_ss(k))*orho(k)/qsz(k))&
634                    **(1./tmp_ss(k))
636             vtsold(k)= sqrho(k)*av_s(k)*ggamma(bv_s(k)+tmp_ss(k))/ &
637                       ggamma(tmp_ss(k))/(tmp1**bv_s(k))
639             if (k .eq. 1) then
640                del_tv=amin1(del_tv,0.9*(zz(k)-zsfc)/vtsold(k))
641             else
642                del_tv=amin1(del_tv,0.9*(zz(k)-zz(k-1))/vtsold(k))
643             endif
644          else
645             vtsold(k)=0.
646          endif
647       enddo
649       if (max_q .ge. min_q) then
652 !- Check if the summation of the small delta t >=  big delta t
653 !             (t_del_tv)          (del_tv)             (dtb)
655          t_del_tv=t_del_tv+del_tv
657          if ( t_del_tv .ge. dtb ) then
658               notlast=.false.
659               del_tv=dtb+del_tv-t_del_tv
660          endif
662          fluxin=0.
663          do k=max_q,min_q,-1
664             fluxout=rho(k)*vtsold(k)*qsz(k)
665             flux=(fluxin-fluxout)/rho(k)/dzw(k)
666             qsz(k)=qsz(k)+del_tv*flux
667             qsz(k)=amax1(0.,qsz(k))
668             fluxin=fluxout
669          enddo
670          if (min_q .eq. 1) then
671             pptsnow=pptsnow+fluxin*del_tv
672          else
673             qsz(min_q-1)=qsz(min_q-1)+del_tv*  &
674                          fluxin/rho(min_q-1)/dzw(min_q-1)
675          endif
677       else
678          notlast=.false.
679       endif
681       ENDDO
684 !-- cloud ice  (03/21/02) using Heymsfield and Donner (1990) Vi=3.29*qi^0.16
686       t_del_tv=0.
687       del_tv=dtb
688       notlast=.true.
690       DO while (notlast)
692       min_q=kte
693       max_q=kts-1
695       do k=kts,kte-1
696          if (qiz(k) .gt. 1.0e-8) then
697             min_q=min0(min_q,k)
698             max_q=max0(max_q,k)
699             vtiold(k)= 3.29 * (rho(k)* qiz(k))** 0.16  ! Heymsfield and Donner
700             if (k .eq. 1) then
701                del_tv=amin1(del_tv,0.9*(zz(k)-zsfc)/vtiold(k))
702             else
703                del_tv=amin1(del_tv,0.9*(zz(k)-zz(k-1))/vtiold(k))
704             endif
705          else
706             vtiold(k)=0.
707          endif
708       enddo
710       if (max_q .ge. min_q) then
712 !- Check if the summation of the small delta t >=  big delta t
713 !             (t_del_tv)          (del_tv)             (dtb)
715          t_del_tv=t_del_tv+del_tv
717          if ( t_del_tv .ge. dtb ) then
718               notlast=.false.
719               del_tv=dtb+del_tv-t_del_tv
720          endif
722          fluxin=0.
723          do k=max_q,min_q,-1
724             fluxout=rho(k)*vtiold(k)*qiz(k)
725             flux=(fluxin-fluxout)/rho(k)/dzw(k)
726             qiz(k)=qiz(k)+del_tv*flux
727             qiz(k)=amax1(0.,qiz(k))
728             fluxin=fluxout
729          enddo
730          if (min_q .eq. 1) then
731             pptice=pptice+fluxin*del_tv
732          else
733             qiz(min_q-1)=qiz(min_q-1)+del_tv*  &
734                          fluxin/rho(min_q-1)/dzw(min_q-1)
735          endif
737       else
738          notlast=.false.
739       endif
741       ENDDO
743 !     CALL wrf_debug ( 100 , 'module_ylin: end precip flux' )
745 ! Microphpysics processes
747       DO 2000 k=kts,kte
749          qvzodt(k)=amax1( 0.0,odtb*qvz(k) )
750          qlzodt(k)=amax1( 0.0,odtb*qlz(k) )
751          qizodt(k)=amax1( 0.0,odtb*qiz(k) )
752          qszodt(k)=amax1( 0.0,odtb*qsz(k) )
753          qrzodt(k)=amax1( 0.0,odtb*qrz(k) )
755 !***********************************************************************
756 !*****   diagnose mixing ratios (qrz,qsz), terminal                *****
757 !*****   velocities (vtr,vts), and slope parameters in size        *****
758 !*****   distribution(xlambdar,xlambdas) of rain and snow          *****
759 !*****   follows Nagata and Ogura, 1991, MWR, 1309-1337. Eq (A7)   *****
760 !***********************************************************************
762 !**** assuming no cloud water can exist in the top two levels due to
763 !**** radiation consideration
765 !!  if
766 !!     unsaturated,
767 !!     no cloud water, rain, ice, snow
768 !!  then
769 !!     skip these processes and jump to line 2000
772         tmp=qiz(k)+qlz(k)+qsz(k)+qrz(k)
773         if( qvz(k)+qlz(k)+qiz(k) .lt. qsiz(k)  &
774             .and. tmp .eq. 0.0 ) go to 2000
776 !! calculate terminal velocity of rain
778         if (qrz(k) .gt. 1.0e-8) then
779             tmp1=sqrt(pi*rhowater*xnor*orho(k)/qrz(k))
780             xlambdar(k)=sqrt(tmp1)
781             olambdar(k)=1.0/xlambdar(k)
782             vtrold(k)=o6*av_r*gambp4*sqrho(k)*olambdar(k)**bv_r
783         else
784             vtrold(k)=0.
785             olambdar(k)=0.
786         endif
788         if (qrz(k) .gt. 1.0e-8) then
789             tmp1=sqrt(pi*rhowater*xnor*orho(k)/qrz(k))
790             xlambdar(k)=sqrt(tmp1)
791             olambdar(k)=1.0/xlambdar(k)
792             vtr(k)=o6*av_r*gambp4*sqrho(k)*olambdar(k)**bv_r
793         else
794             vtr(k)=0.
795             olambdar(k)=0.
796         endif
798 !! calculate terminal velocity of snow
800         if (qsz(k) .gt. 1.0e-8) then
801             tmp1= (am_s(k)*N0_s(k)*ggamma(tmp_ss(k))*orho(k)/qsz(k))&
802                    **(1./tmp_ss(k))
803             olambdas(k)=1.0/tmp1
804             vtsold(k)= sqrho(k)*av_s(k)*ggamma(bv_s(k)+tmp_ss(k))/ &
805                       ggamma(tmp_ss(k))/(tmp1**bv_s(k))
807         else
808             vtsold(k)=0.
809             olambdas(k)=0.
810         endif
812         if (qsz(k) .gt. 1.0e-8) then
813              tmp1= (am_s(k)*N0_s(k)*ggamma(tmp_ss(k))*orho(k)/qsz(k))&
814                    **(1./tmp_ss(k))
815              olambdas(k)=1.0/tmp1
816              vts(k)= sqrho(k)*av_s(k)*ggamma(bv_s(k)+tmp_ss(k))/ &
817                       ggamma(tmp_ss(k))/(tmp1**bv_s(k))
819         else
820             vts(k)=0.
821             olambdas(k)=0.
822         endif
824 !---------- start of snow/ice processes below freezing
826         if (tem(k) .lt. 273.15) then
829 !***********************************************************************
830 !*********        snow production processes for T < 0 C       **********
831 !***********************************************************************
833 !c (1) ICE CRYSTAL AGGREGATION TO SNOW (Psaut): Lin (21)
834 !c!    psaut=alpha1*(qi-qi0)
835 !c!    alpha1=1.0e-3*exp(0.025*(T-T0))
837            alpha1=1.0e-3*exp( 0.025*temcc(k) )
839            if(temcc(k) .lt. -20.0) then
840              tmp1=-7.6+4.0*exp( -0.2443e-3*(abs(temcc(k))-20)**2.455 )
841              qic=1.0e-3*exp(tmp1)*orho(k)
842            else
843              qic=qi0
844            end if
846            tmp1=odtb*(qiz(k)-qic)*(1.0-exp(-alpha1*dtb))
847            psaut(k)=amax1( 0.0,tmp1 )
850 !c (2) BERGERON PROCESS TRANSFER OF CLOUD WATER TO SNOW (Psfw)
851 !c     this process only considered when -31 C < T < 0 C
852 !c     Lin (33) and Hsie (17)
855 !c!    parama1 and parama2 functions must be user supplied
858           if( qlz(k) .gt. 1.0e-10 ) then
859             temc1=amax1(-30.99,temcc(k))
860             a1=parama1( temc1 )
861             a2=parama2( temc1 )
862             tmp1=1.0-a2
863 !!   change unit from cgs to mks
864             a1=a1*0.001**tmp1
865 !!   dtberg is the time needed for a crystal to grow from 40 to 50 um
866 !!   odtberg=1.0/dtberg
867             odtberg=(a1*tmp1)/(xmi50**tmp1-xmi40**tmp1)
869 !!   compute terminal velocity of a 50 micron ice cystal
871             vti50=av_i*di50**bv_i*sqrho(k)
873             eiw=1.0
874             save1=a1*xmi50**a2
875             save2=0.25*pi*eiw*rho(k)*di50*di50*vti50
877             tmp2=( save1 + save2*qlz(k) )
879 !!  maximum number of 50 micron crystals limited by the amount
880 !!  of supercool water
882             xni50mx=qlzodt(k)/tmp2
884 !!   number of 50 micron crystals produced
886             xni50=qiz(k)*( 1.0-exp(-dtb*odtberg) )/xmi50
887             xni50=amin1(xni50,xni50mx)
889             tmp3=odtb*tmp2/save2*( 1.0-exp(-save2*xni50*dtb) )
890             psfw(k)=amin1( tmp3,qlzodt(k) )
892 !c (3) REDUCTION OF CLOUD ICE BY BERGERON PROCESS (Psfi): Lin (34)
893 !c     this process only considered when -31 C < T < 0 C
895             tmp1=xni50*xmi50-psfw(k)
896             psfi(k)=amin1(tmp1,qizodt(k))
897           end if
900           if(qrz(k) .le. 0.0) go to 1000
902 ! Processes (4) and (5) only need when qrz > 0.0
905 !c (4) CLOUD ICE ACCRETION BY RAIN (Praci): Lin (25)
906 !c     produce PI
908           eri=1.0
909           save1=pio4*eri*xnor*av_r*sqrho(k)
910           tmp1=save1*gambp3*olambdar(k)**bp3
911           praci(k)=qizodt(k)*( 1.0-exp(-tmp1*dtb) )
914 !c (5) RAIN ACCRETION BY CLOUD ICE (Piacr): Lin (26)
916           tmp2=qiz(k)*save1*rho(k)*pio6*rhowater*gambp6*oxmi* &
917                    olambdar(k)**bp6
918           piacr(k)=amin1( tmp2,qrzodt(k) )
921 1000      continue
923           if(qsz(k) .le. 0.0) go to 1200
925 ! Compute the following processes only when qsz > 0.0
928 !c (6) ICE CRYSTAL ACCRETION BY SNOW (Psaci): Lin (22)
930           esi=exp( 0.025*temcc(k) )
931           save1 = aa_s(k)*sqrho(k)*N0_s(k)* &
932                   ggamma(bv_s(k)+tmp_sa(k))*olambdas(k)**(bv_s(k)+tmp_sa(k))
934           tmp1=esi*save1
935           psaci(k)=qizodt(k)*( 1.0-exp(-tmp1*dtb) )
938 !c (7) CLOUD WATER ACCRETION BY SNOW (Psacw): Lin (24)
940           esw=1.0
941           tmp1=esw*save1
942           psacw(k)=qlzodt(K)*( 1.0-exp(-tmp1*dtb) )
945 !c (8) DEPOSITION/SUBLIMATION OF SNOW (Psdep/Pssub): Lin (31)
946 !c     includes consideration of ventilation effect
948           tmpa=rvapor*xka(k)*tem(k)*tem(k)
949           tmpb=xls*xls*rho(k)*qsiz(k)*diffwv(k)
950           tmpc=tmpa*qsiz(k)*diffwv(k)
951           abi=4.0*pi*cap_s(k)*(qvoqsiz(k)-1.0)*tmpc/(tmpa+tmpb)
952           tmp1=av_s(k)*sqrho(k)*olambdas(k)**(5+bv_s(k)+2*mu_s)/visc(k)
954 !---- YLIN, here there is some approximation assuming mu_s =1, so gamma(2)=1, etc.
956           tmp2= abi*N0_s(k)*( vf1s*olambdas(k)*olambdas(k)+ &
957                 vf2s*schmidt(k)**0.33334* &
958                 ggamma(2.5+0.5*bv_s(k)+mu_s)*sqrt(tmp1) )
960           tmp3=odtb*( qvz(k)-qsiz(k) )
962           if( tmp2 .le. 0.0) then
963             tmp2=amax1( tmp2,tmp3)
964             pssub(k)=amax1( tmp2,-qszodt(k) )
965             psdep(k)=0.0
966           else
967             psdep(k)=amin1( tmp2,tmp3 )
968             pssub(k)=0.0
969           end if
972           if(qrz(k) .le. 0.0) go to 1200
974 ! Compute processes (9) and (10) only when qsz > 0.0 and qrz > 0.0
975 ! these two terms need to be refined in the future, they should be equal
977 !c (9) ACCRETION OF SNOW BY RAIN (Pracs): Lin (27)
979           esr=1.0
980           tmpa=olambdar(k)*olambdar(k)
981           tmpb=olambdas(k)*olambdas(k)
982           tmpc=olambdar(k)*olambdas(k)
983           tmp1=pi*pi*esr*xnor*N0_s(k)*abs( vtr(k)-vts(k) )*orho(k)
984           tmp2=tmpb*tmpb*olambdar(k)*(5.0*tmpb+2.0*tmpc+0.5*tmpa)
985           tmp3=tmp1*rhosnow*tmp2
986           pracs(k)=amin1( tmp3,qszodt(k) )
987           pracs(k)=0.0
989 !c (10) ACCRETION OF RAIN BY SNOW (Psacr): Lin (28)
991           tmp3=tmpa*tmpa*olambdas(k)*(5.0*tmpa+2.0*tmpc+0.5*tmpb)
992           tmp4=tmp1*rhowater*tmp3
993           psacr(k)=amin1( tmp4,qrzodt(k) )
996 !c (2) FREEZING OF RAIN TO FORM GRAUPEL  (pgfr): Lin (45), added to PI
997 !c     positive value
998 !c     Constant in Bigg freezing Aplume=Ap=0.66 /k
999 !c     Constant in raindrop freezing equ. Bplume=Bp=100./m/m/m/s
1002             if (qrz(k) .gt. 1.e-8 ) then
1003                Bp=100.
1004                Ap=0.66
1005                tmp1=olambdar(k)*olambdar(k)*olambdar(k)
1006                tmp2=20.*pi*pi*Bp*xnor*rhowater*orho(k)*  &
1007                     (exp(-Ap*temcc(k))-1.0)*tmp1*tmp1*olambdar(k)
1008                pgfr(k)=amin1( tmp2,qrzodt(k) )
1009             else
1010                pgfr(k)=0
1011             endif
1013 1200      continue
1016         else                        
1019 !***********************************************************************
1020 !*********        snow production processes for T > 0 C       **********
1021 !***********************************************************************
1023          if (qsz(k) .le. 0.0) go to 1400
1025 !c (1) CLOUD WATER ACCRETION BY SNOW (Psacw): Lin (24)
1027             esw=1.0
1029             save1 =aa_s(k)*sqrho(k)*N0_s(k)* &
1030                    ggamma(bv_s(k)+tmp_sa(k))*olambdas(k)**(bv_s(k)+tmp_sa(k))
1032             tmp1=esw*save1
1033             psacw(k)=qlzodt(k)*( 1.0-exp(-tmp1*dtb) )
1036 !c (2) ACCRETION OF RAIN BY SNOW (Psacr): Lin (28)
1038             esr=1.0
1039             tmpa=olambdar(k)*olambdar(k)
1040             tmpb=olambdas(k)*olambdas(k)
1041             tmpc=olambdar(k)*olambdas(k)
1042             tmp1=pi*pi*esr*xnor*N0_s(k)*abs( vtr(k)-vts(k) )*orho(k)
1043             tmp2=tmpa*tmpa*olambdas(k)*(5.0*tmpa+2.0*tmpc+0.5*tmpb)
1044             tmp3=tmp1*rhowater*tmp2
1045             psacr(k)=amin1( tmp3,qrzodt(k) )
1047 !c (3) MELTING OF SNOW (Psmlt): Lin (32)
1048 !c     Psmlt is negative value
1050             delrs=rs0(k)-qvz(k)
1051             term1=2.0*pi*orho(k)*( xlv*diffwv(k)*rho(k)*delrs- &
1052                   xka(k)*temcc(k) )
1053             tmp1= av_s(k)*sqrho(k)*olambdas(k)**(5+bv_s(k)+2*mu_s)/visc(k)
1054             tmp2= N0_s(k)*( vf1s*olambdas(k)*olambdas(k)+ &
1055                   vf2s*schmidt(k)**0.33334* &
1056                   ggamma(2.5+0.5*bv_s(k)+mu_s)*sqrt(tmp1) )
1057             tmp3=term1*oxlf*tmp2-cwoxlf*temcc(k)*( psacw(k)+psacr(k) )
1058             tmp4=amin1(0.0,tmp3)
1059             psmlt(k)=amax1( tmp4,-qszodt(k) )
1061 !c (4) EVAPORATION OF MELTING SNOW (Psmltevp): HR (A27)
1062 !c     but use Lin et al. coefficience
1063 !c     Psmltevp is a negative value
1065             tmpa=rvapor*xka(k)*tem(k)*tem(k)
1066             tmpb=xlv*xlv*rho(k)*qswz(k)*diffwv(k)
1067             tmpc=tmpa*qswz(k)*diffwv(k)
1068             tmpd=amin1( 0.0,(qvoqswz(k)-0.90)*qswz(k)*odtb )
1070             abr=2.0*pi*(qvoqswz(k)-0.90)*tmpc/(tmpa+tmpb)
1072 !**** allow evaporation to occur when RH less than 90%
1073 !**** here not using 100% because the evaporation cooling
1074 !**** of temperature is not taking into account yet; hence,
1075 !**** the qsw value is a little bit larger. This will avoid
1076 !**** evaporation can generate cloud.
1078             tmp1=av_s(k)*sqrho(k)*olambdas(k)**(5+bv_s(k)+2*mu_s)/visc(k)
1079             tmp2= N0_s(k)*( vf1s*olambdas(k)*olambdas(k)+ &
1080                   vf2s*schmidt(k)**0.33334* &
1081                   ggamma(2.5+0.5*bv_s(k)+mu_s)*sqrt(tmp1) )
1082             tmp3=amin1(0.0,tmp2)
1083             tmp3=amax1( tmp3,tmpd )
1084             psmltevp(k)=amax1( tmp3,-qszodt(k) )
1085 1400     continue
1087         end if      !---- end of snow/ice processes
1089 !         CALL wrf_debug ( 100 , 'module_ylin: finish ice/snow processes' )
1092 !***********************************************************************
1093 !*********           rain production processes                **********
1094 !***********************************************************************
1097 !c (1) AUTOCONVERSION OF RAIN (Praut): using Liu and Daum (2004)
1100 !---- YLIN, autoconversion use Liu and Daum (2004), unit = g cm-3 s-1, in the scheme kg/kg s-1, so
1102        if (qlz(k) .gt. 1e-6) then
1103            lamc(k) = (Nt_c*rhowater*pi*ggamma(4.+mu_c)/(6.*rho(k)*qlz(k))/ &        !--- N(D) = N0*D^mu*exp(-lamc*D)
1104                     ggamma(1+mu_c))**0.3333
1105            Dc_liu  = (ggamma(6+1+mu_c)/ggamma(1+mu_c))**(1./6.)/lamc(k)             !----- R6 in m
1107            if (Dc_liu .gt. R6c) then
1108              disp = 1./(mu_c+1.)      !--- square of relative dispersion
1109              eta  = (0.75/pi/(1e-3*rhowater))**2*1.9e11*((1+3*disp)*(1+4*disp)*&
1110                    (1+5*disp)/(1+disp)/(1+2*disp))
1111              praut(k) = eta*(1e-3*rho(k)*qlz(k))**3/(1e-6*Nt_c)                      !--- g cm-3 s-1
1112              praut(k) = praut(k)/(1e-3*rho(k))                                       !--- kg kg-1 s-1
1113            else
1114             praut(k) = 0.0
1115            endif
1116        else
1117          praut(k) = 0.0
1118        endif 
1121 !c (2) ACCRETION OF CLOUD WATER BY RAIN (Pracw): Lin (51)
1123         erw=1.0
1125         tmp1=pio4*erw*xnor*av_r*sqrho(k)* &
1126              gambp3*olambdar(k)**bp3
1127         pracw(k)=qlzodt(k)*( 1.0-exp(-tmp1*dtb) )
1130 !c (3) EVAPORATION OF RAIN (Prevp): Lin (52)
1131 !c     Prevp is negative value
1133 !c     Sw=qvoqsw : saturation ratio
1135          tmpa=rvapor*xka(k)*tem(k)*tem(k)
1136          tmpb=xlv*xlv*rho(k)*qswz(k)*diffwv(k)
1137          tmpc=tmpa*qswz(k)*diffwv(k)
1138          tmpd=amin1(0.0,(qvoqswz(k)-0.90)*qswz(k)*odtb)
1140          abr=2.0*pi*(qvoqswz(k)-0.90)*tmpc/(tmpa+tmpb)
1141          tmp1=av_r*sqrho(k)*olambdar(k)**bp5/visc(k)
1142          tmp2=abr*xnor*( vf1r*olambdar(k)*olambdar(k)+  &
1143               vf2r*schmidt(k)**0.33334*gambp5o2*sqrt(tmp1) )
1144          tmp3=amin1( 0.0,tmp2 )
1145          tmp3=amax1( tmp3,tmpd )
1146          prevp(k)=amax1( tmp3,-qrzodt(k) )
1148 !        CALL wrf_debug ( 100 , 'module_ylin: finish rain processes' )
1151 !c**********************************************************************
1152 !c*****     combine all processes together and avoid negative      *****
1153 !c*****     water substances
1154 !***********************************************************************
1156       if ( temcc(k) .lt. 0.0) then
1158 !c  combined water vapor depletions
1160            tmp=psdep(k)
1161            if ( tmp .gt. qvzodt(k) ) then
1162               factor=qvzodt(k)/tmp
1163               psdep(k)=psdep(k)*factor
1164            end if
1166 !c  combined cloud water depletions
1168            tmp=praut(k)+psacw(k)+psfw(k)+pracw(k)
1169            if ( tmp .gt. qlzodt(k) ) then
1170               factor=qlzodt(k)/tmp
1171               praut(k)=praut(k)*factor
1172               psacw(k)=psacw(k)*factor
1173               psfw(k)=psfw(k)*factor
1174               pracw(k)=pracw(k)*factor
1175            end if
1177 !c  combined cloud ice depletions
1179            tmp=psaut(k)+psaci(k)+praci(k)+psfi(k)
1180            if (tmp .gt. qizodt(k) ) then
1181               factor=qizodt(k)/tmp
1182               psaut(k)=psaut(k)*factor
1183               psaci(k)=psaci(k)*factor
1184               praci(k)=praci(k)*factor
1185               psfi(k)=psfi(k)*factor
1186            endif
1188 !c  combined all rain processes
1190           tmp_r=piacr(k)+psacr(k)-prevp(k)-praut(k)-pracw(k)+pgfr(k) 
1191           if (tmp_r .gt. qrzodt(k) ) then
1192              factor=qrzodt(k)/tmp_r
1193              piacr(k)=piacr(k)*factor
1194              psacr(k)=psacr(k)*factor
1195              prevp(k)=prevp(k)*factor
1196              pgfr(k)=pgfr(k)*factor
1197           endif
1199 !c   combined all snow processes
1201           tmp_s=-pssub(k)-(psaut(k)+psaci(k)+psacw(k)+psfw(k)+pgfr(k)+ &
1202                  psfi(k)+praci(k)+piacr(k)+ &
1203                  psdep(k)+psacr(k)-pracs(k))
1204           if ( tmp_s .gt. qszodt(k) ) then
1205              factor=qszodt(k)/tmp_s
1206              pssub(k)=pssub(k)*factor
1207              Pracs(k)=Pracs(k)*factor
1208           endif
1211 !c  calculate new water substances, thetae, tem, and qvsbar
1214          pvapor(k)=-pssub(k)-psdep(k)-prevp(k)
1215          qvz(k)=amax1( qvmin,qvz(k)+dtb*pvapor(k) )
1216          pclw(k)=-praut(k)-pracw(k)-psacw(k)-psfw(k)
1217          qlz(k)=amax1( 0.0,qlz(k)+dtb*pclw(k) )
1218          pcli(k)=-psaut(k)-psfi(k)-psaci(k)-praci(k)
1219          qiz(k)=amax1( 0.0,qiz(k)+dtb*pcli(k) )
1220          tmp_r=piacr(k)+psacr(k)-prevp(k)-praut(k)-pracw(k)+pgfr(k)-pracs(k) 
1221          prain(k)=-tmp_r
1222          qrz(k)=amax1( 0.0,qrz(k)+dtb*prain(k) )
1223          tmp_s=-pssub(k)-(psaut(k)+psaci(k)+psacw(k)+psfw(k)+pgfr(k)+  &
1224                 psfi(k)+praci(k)+piacr(k)+  &
1225                 psdep(k)+psacr(k)-pracs(k))
1226          psnow(k)=-tmp_s
1227          qsz(k)=amax1( 0.0,qsz(k)+dtb*psnow(k) )
1229          qschg(k)=qschg(k)+psnow(k)
1230          qschg(k)=psnow(k)
1232          tmp=ocp/tothz(k)*xLf*qschg(k)
1233          theiz(k)=theiz(k)+dtb*tmp
1234          thz(k)=theiz(k)-(xLvocp*qvz(k)-xLfocp*qiz(k))/tothz(k)
1235          tem(k)=thz(k)*tothz(k)
1237          temcc(k)=tem(k)-273.15
1239          if( temcc(k) .lt. -40.0 ) qswz(k)=qsiz(k)
1240          qlpqi=qlz(k)+qiz(k)
1241          if ( qlpqi .eq. 0.0 ) then
1242             qvsbar(k)=qsiz(k)
1243          else
1244             qvsbar(k)=( qiz(k)*qsiz(k)+qlz(k)*qswz(k) )/qlpqi
1245          endif
1248       else                  !>0 C
1250 !c  combined cloud water depletions
1252           tmp=praut(k)+psacw(k)+pracw(k)
1253           if ( tmp .gt. qlzodt(k) ) then
1254              factor=qlzodt(k)/tmp
1255              praut(k)=praut(k)*factor
1256              psacw(k)=psacw(k)*factor
1257              pracw(k)=pracw(k)*factor
1258           end if
1260 !c  combined all snow processes
1262           tmp_s=-(psmlt(k)+psmltevp(k))
1263           if (tmp_s .gt. qszodt(k) ) then
1264              factor=qszodt(k)/tmp_s
1265              psmlt(k)=psmlt(k)*factor
1266              psmltevp(k)=psmltevp(k)*factor
1267           endif
1269 !c  combined all rain processes
1271           tmp_r=-prevp(k)-(praut(k)+pracw(k)+psacw(k)-psmlt(k)) 
1272           if (tmp_r .gt. qrzodt(k) ) then
1273              factor=qrzodt(k)/tmp_r
1274              prevp(k)=prevp(k)*factor
1275           endif
1277 !c  calculate new water substances and thetae
1279           pvapor(k)=-psmltevp(k)-prevp(k)
1280           qvz(k)=amax1( qvmin,qvz(k)+dtb*pvapor(k))
1281           pclw(k)=-praut(k)-pracw(k)-psacw(k)
1282           qlz(k)=amax1( 0.0,qlz(k)+dtb*pclw(k) )
1283           pcli(k)=0.0
1284           qiz(k)=amax1( 0.0,qiz(k)+dtb*pcli(k) )
1285           tmp_r=-prevp(k)-(praut(k)+pracw(k)+psacw(k)-psmlt(k)) 
1286           prain(k)=-tmp_r
1287           tmpqrz=qrz(k)
1288           qrz(k)=amax1( 0.0,qrz(k)+dtb*prain(k) )
1289           tmp_s=-(psmlt(k)+psmltevp(k))
1290           psnow(k)=-tmp_s
1291           qsz(k)=amax1( 0.0,qsz(k)+dtb*psnow(k) )
1292           qschg(k)=psnow(k)
1294           tmp=ocp/tothz(k)*xLf*qschg(k)
1295           theiz(k)=theiz(k)+dtb*tmp
1296           thz(k)=theiz(k)-(xLvocp*qvz(k)-xLfocp*qiz(k))/tothz(k)
1298           tem(k)=thz(k)*tothz(k)
1299           temcc(k)=tem(k)-273.15
1300           es=1000.*svp1*exp( svp2*temcc(k)/(tem(k)-svp3) )
1301           qswz(k)=ep2*es/(prez(k)-es)
1302           qsiz(k)=qswz(k)
1303           qvsbar(k)=qswz(k)
1305       end if
1306 !      CALL wrf_debug ( 100 , 'module_ylin: finish sum of all processes' )
1309 !***********************************************************************
1310 !**********              saturation adjustment                **********
1311 !***********************************************************************
1313 !    allow supersaturation exits linearly from 0% at 500 mb to 50%
1314 !    above 300 mb
1315 !    5.0e-5=1.0/(500mb-300mb)
1317          rsat=1.0
1318          if( qvz(k)+qlz(k)+qiz(k) .lt. rsat*qvsbar(k) ) then
1321 !c   unsaturated
1323           qvz(k)=qvz(k)+qlz(k)+qiz(k)
1324           qlz(k)=0.0
1325           qiz(k)=0.0
1327           thz(k)=theiz(k)-(xLvocp*qvz(k)-xLfocp*qiz(k))/tothz(k)
1328           tem(k)=thz(k)*tothz(k)
1329           temcc(k)=tem(k)-273.15
1331           go to 1800
1333         else
1335 !c   saturated
1337           pladj(k)=qlz(k)
1338           piadj(k)=qiz(k)
1341         CALL satadj(qvz, qlz, qiz, prez, theiz, thz, tothz, kts, kte, &
1342                     k, xLvocp, xLfocp, episp0k, EP2,SVP1,SVP2,SVP3,SVPT0)
1345           pladj(k)=odtb*(qlz(k)-pladj(k))
1346           piadj(k)=odtb*(qiz(k)-piadj(k))
1348           pclw(k)=pclw(k)+pladj(k)
1349           pcli(k)=pcli(k)+piadj(k)
1350           pvapor(k)=pvapor(k)-( pladj(k)+piadj(k) )
1352           thz(k)=theiz(k)-(xLvocp*qvz(k)-xLfocp*qiz(k))/tothz(k)
1353           tem(k)=thz(k)*tothz(k)
1355           temcc(k)=tem(k)-273.15
1357           es=1000.*svp1*exp( svp2*temcc(k)/(tem(k)-svp3) )
1358           qswz(k)=ep2*es/(prez(k)-es)
1359           if (tem(k) .lt. 273.15 ) then
1360              es=1000.*svp1*exp( 21.8745584*(tem(k)-273.16)/(tem(k)-7.66) )
1361              qsiz(k)=ep2*es/(prez(k)-es)
1362              if (temcc(k) .lt. -40.0) qswz(k)=qsiz(k)
1363           else
1364              qsiz(k)=qswz(k)
1365           endif
1366           qlpqi=qlz(k)+qiz(k)
1367           if ( qlpqi .eq. 0.0 ) then
1368              qvsbar(k)=qsiz(k)
1369           else
1370              qvsbar(k)=( qiz(k)*qsiz(k)+qlz(k)*qswz(k) )/qlpqi
1371           endif
1373         end if
1376 !***********************************************************************
1377 !*****     melting and freezing of cloud ice and cloud water       *****
1378 !***********************************************************************
1379         qlpqi=qlz(k)+qiz(k)
1380         if(qlpqi .le. 0.0) go to 1800
1383 !c (1)  HOMOGENEOUS NUCLEATION WHEN T< -40 C (Pihom)
1385         if(temcc(k) .lt. -40.0) pihom(k)=qlz(k)*odtb
1387 !c (2)  MELTING OF ICE CRYSTAL WHEN T> 0 C (Pimlt)
1389         if(temcc(k) .gt. 0.0) pimlt(k)=qiz(k)*odtb
1391 !c (3) PRODUCTION OF CLOUD ICE BY BERGERON PROCESS (Pidw): Hsie (p957)
1392 !c     this process only considered when -31 C < T < 0 C
1394         if(temcc(k) .lt. 0.0 .and. temcc(k) .gt. -31.0) then
1396 !c!   parama1 and parama2 functions must be user supplied
1398           a1=parama1( temcc(k) )
1399           a2=parama2( temcc(k) )
1400 !! change unit from cgs to mks
1401           a1=a1*0.001**(1.0-a2)
1402           xnin=xni0*exp(-bni*temcc(k))
1403           pidw(k)=xnin*orho(k)*(a1*xmnin**a2)
1404         end if
1406         pcli(k)=pcli(k)+pihom(k)-pimlt(k)+pidw(k)
1407         pclw(k)=pclw(k)-pihom(k)+pimlt(k)-pidw(k)
1408         qlz(k)=amax1( 0.0,qlz(k)+dtb*(-pihom(k)+pimlt(k)-pidw(k)) )
1409         qiz(k)=amax1( 0.0,qiz(k)+dtb*(pihom(k)-pimlt(k)+pidw(k)) )
1412         CALL satadj(qvz, qlz, qiz, prez, theiz, thz, tothz, kts, kte, &
1413                     k, xLvocp, xLfocp, episp0k ,EP2,SVP1,SVP2,SVP3,SVPT0)
1415         thz(k)=theiz(k)-(xLvocp*qvz(k)-xLfocp*qiz(k))/tothz(k)
1416         tem(k)=thz(k)*tothz(k)
1418         temcc(k)=tem(k)-273.15
1420         es=1000.*svp1*exp( svp2*temcc(k)/(tem(k)-svp3) )
1421         qswz(k)=ep2*es/(prez(k)-es)
1423         if (tem(k) .lt. 273.15 ) then
1424            es=1000.*svp1*exp( 21.8745584*(tem(k)-273.16)/(tem(k)-7.66) )
1425            qsiz(k)=ep2*es/(prez(k)-es)
1426            if (temcc(k) .lt. -40.0) qswz(k)=qsiz(k)
1427         else
1428            qsiz(k)=qswz(k)
1429         endif
1430         qlpqi=qlz(k)+qiz(k)
1432         if ( qlpqi .eq. 0.0 ) then
1433            qvsbar(k)=qsiz(k)
1434         else
1435            qvsbar(k)=( qiz(k)*qsiz(k)+qlz(k)*qswz(k) )/qlpqi
1436         endif
1438 1800  continue
1440 !***********************************************************************
1441 !**********    integrate the productions of rain and snow     **********
1442 !***********************************************************************
1444 2000  continue
1447 !**** below if qv < qvmin then qv=qvmin, ql=0.0, and qi=0.0
1449       do k=kts+1,kte
1450          if ( qvz(k) .lt. qvmin ) then
1451             qlz(k)=0.0
1452             qiz(k)=0.0
1453             qvz(k)=amax1( qvmin,qvz(k)+qlz(k)+qiz(k) )
1454          end if
1455       enddo
1458 !      CALL wrf_debug ( 100 , 'module_ylin: finish saturation adjustment' )
1460       END SUBROUTINE clphy1d_ylin
1465 !---------------------------------------------------------------------
1466 !                         SATURATED ADJUSTMENT
1467 !---------------------------------------------------------------------
1468       SUBROUTINE satadj(qvz, qlz, qiz, prez, theiz, thz, tothz,      &
1469                         kts, kte, k, xLvocp, xLfocp, episp0k, EP2,SVP1,SVP2,SVP3,SVPT0)
1470 !---------------------------------------------------------------------
1471       IMPLICIT NONE
1472 !---------------------------------------------------------------------
1473 !  This program use Newton's method for finding saturated temperature
1474 !  and saturation mixing ratio.
1476 ! In this saturation adjustment scheme we assume
1477 ! (1)  the saturation mixing ratio is the mass weighted average of
1478 !      saturation values over liquid water (qsw), and ice (qsi)
1479 !      following Lord et al., 1984 and Tao, 1989
1481 ! (2) the percentage of cloud liquid and cloud ice will
1482 !      be fixed during the saturation calculation
1483 !---------------------------------------------------------------------
1486      INTEGER, INTENT(IN   )             :: kts, kte, k
1488      REAL,      DIMENSION( kts:kte ),                                   &
1489                        INTENT(INOUT) :: qvz, qlz, qiz
1491      REAL,      DIMENSION( kts:kte ),                                   &
1492                        INTENT(IN   ) :: prez, theiz, tothz
1494      REAL,     INTENT(IN   )            :: xLvocp, xLfocp, episp0k
1495      REAL,     INTENT(IN   )            :: EP2,SVP1,SVP2,SVP3,SVPT0
1497 ! LOCAL VARS
1499      INTEGER                            :: n
1501      REAL, DIMENSION( kts:kte )         :: thz, tem, temcc, qsiz,       &
1502                                         qswz, qvsbar
1504      REAL :: qsat, qlpqi, ratql, t0, t1, tmp1, ratqi, tsat, absft,    &
1505              denom1, denom2, dqvsbar, ftsat, dftsat, qpz,es             
1507 !---------------------------------------------------------------------
1509       thz(k)=theiz(k)-(xLvocp*qvz(k)-xLfocp*qiz(k))/tothz(k)
1511       tem(k)=tothz(k)*thz(k)
1512       if (tem(k) .gt. 273.15) then
1513 !        qsat=episp0k/prez(k)*  &
1514 !            exp( svp2*(tem(k)-273.15)/(tem(k)-svp3) )
1515          es=1000.*svp1*exp( svp2*(tem(k)-svpt0)/(tem(k)-svp3) )
1516          qsat=ep2*es/(prez(k)-es)
1517       else
1518         qsat=episp0k/prez(k)*  &
1519              exp( 21.8745584*(tem(k)-273.15)/(tem(k)-7.66) )
1520       end if
1521       qpz=qvz(k)+qlz(k)+qiz(k)
1522       if (qpz .lt. qsat) then
1523          qvz(k)=qpz
1524          qiz(k)=0.0
1525          qlz(k)=0.0
1526          go to 400
1527       end if
1528       qlpqi=qlz(k)+qiz(k)
1529       if( qlpqi .ge. 1.0e-5) then
1530         ratql=qlz(k)/qlpqi
1531         ratqi=qiz(k)/qlpqi
1532       else
1533         t0=273.15
1534 !       t1=233.15
1535         t1=248.15
1536         tmp1=( t0-tem(k) )/(t0-t1)
1537         tmp1=amin1(1.0,tmp1)
1538         tmp1=amax1(0.0,tmp1)
1539         ratqi=tmp1
1540         ratql=1.0-tmp1
1541       end if
1544 !--  saturation mixing ratios over water and ice
1545 !--  at the outset we will follow Bolton 1980 MWR for
1546 !--  the water and Murray JAS 1967 for the ice
1548 !-- dqvsbar=d(qvsbar)/dT
1549 !-- ftsat=F(Tsat)
1550 !-- dftsat=d(F(T))/dT
1552 !  First guess of tsat
1554       tsat=tem(k)
1555       absft=1.0
1557       do 200 n=1,20
1558          denom1=1.0/(tsat-svp3)
1559          denom2=1.0/(tsat-7.66)
1560 !        qswz(k)=episp0k/prez(k)*  &
1561 !                exp( svp2*denom1*(tsat-273.15) )
1562          es=1000.*svp1*exp( svp2*denom1*(tsat-svpt0) )
1563          qswz(k)=ep2*es/(prez(k)-es)
1564          if (tem(k) .lt. 273.15) then
1565 !           qsiz(k)=episp0k/prez(k)*  &
1566 !                   exp( 21.8745584*denom2*(tsat-273.15) )
1567             es=1000.*svp1*exp( 21.8745584*denom2*(tsat-273.15) )
1568             qsiz(k)=ep2*es/(prez(k)-es)
1569             if (tem(k) .lt. 233.15) qswz(k)=qsiz(k)
1570          else
1571             qsiz(k)=qswz(k)
1572          endif
1573          qvsbar(k)=ratql*qswz(k)+ratqi*qsiz(k)
1575 !        if( absft .lt. 0.01 .and. n .gt. 3 ) go to 300
1576          if( absft .lt. 0.01 ) go to 300
1578          dqvsbar=ratql*qswz(k)*svp2*243.5*denom1*denom1+  &
1579                  ratqi*qsiz(k)*21.8745584*265.5*denom2*denom2
1580          ftsat=tsat+(xlvocp+ratqi*xlfocp)*qvsbar(k)-  &
1581                tothz(k)*theiz(k)-xlfocp*ratqi*(qvz(k)+qlz(k)+qiz(k))
1582          dftsat=1.0+(xlvocp+ratqi*xlfocp)*dqvsbar
1583          tsat=tsat-ftsat/dftsat
1584          absft=abs(ftsat)
1586 200   continue
1587 9020  format(1x,'point can not converge, absft,n=',e12.5,i5)
1588 300   continue
1590       if( qpz .gt. qvsbar(k) ) then
1591         qvz(k)=qvsbar(k)
1592         qiz(k)=ratqi*( qpz-qvz(k) )
1593         qlz(k)=ratql*( qpz-qvz(k) )
1594       else
1595         qvz(k)=qpz
1596         qiz(k)=0.0
1597         qlz(k)=0.0
1598       end if
1599 400  continue
1601       END SUBROUTINE satadj
1604 !----------------------------------------------------------------
1605      REAL FUNCTION parama1(temp)
1606 !----------------------------------------------------------------
1607       IMPLICIT NONE
1608 !----------------------------------------------------------------
1609 !  This program calculate the parameter for crystal growth rate
1610 !  in Bergeron process
1611 !----------------------------------------------------------------
1613       REAL, INTENT (IN   )   :: temp
1614       REAL, DIMENSION(32)    :: a1
1615       INTEGER                :: i1, i1p1
1616       REAL                   :: ratio
1618       data a1/0.100e-10,0.7939e-7,0.7841e-6,0.3369e-5,0.4336e-5, &
1619               0.5285e-5,0.3728e-5,0.1852e-5,0.2991e-6,0.4248e-6, &
1620               0.7434e-6,0.1812e-5,0.4394e-5,0.9145e-5,0.1725e-4, &
1621               0.3348e-4,0.1725e-4,0.9175e-5,0.4412e-5,0.2252e-5, &
1622               0.9115e-6,0.4876e-6,0.3473e-6,0.4758e-6,0.6306e-6, &
1623               0.8573e-6,0.7868e-6,0.7192e-6,0.6513e-6,0.5956e-6, &
1624               0.5333e-6,0.4834e-6/
1626       i1=int(-temp)+1
1627       i1p1=i1+1
1628       ratio=-(temp)-float(i1-1)
1629       parama1=a1(i1)+ratio*( a1(i1p1)-a1(i1) )
1631       END FUNCTION parama1
1633 !----------------------------------------------------------------
1634       REAL FUNCTION parama2(temp)
1635 !----------------------------------------------------------------
1636       IMPLICIT NONE
1637 !----------------------------------------------------------------
1638 !  This program calculate the parameter for crystal growth rate
1639 !  in Bergeron process
1640 !----------------------------------------------------------------
1642       REAL, INTENT (IN   )   :: temp
1643       REAL, DIMENSION(32)    :: a2
1644       INTEGER                :: i1, i1p1
1645       REAL                   :: ratio
1647       data a2/0.0100,0.4006,0.4831,0.5320,0.5307,0.5319,0.5249, &
1648               0.4888,0.3849,0.4047,0.4318,0.4771,0.5183,0.5463, &
1649               0.5651,0.5813,0.5655,0.5478,0.5203,0.4906,0.4447, &
1650               0.4126,0.3960,0.4149,0.4320,0.4506,0.4483,0.4460, &
1651               0.4433,0.4413,0.4382,0.4361/
1652       i1=int(-temp)+1
1653       i1p1=i1+1
1654       ratio=-(temp)-float(i1-1)
1655       parama2=a2(i1)+ratio*( a2(i1p1)-a2(i1) )
1657       END FUNCTION parama2
1659 !+---+-----------------------------------------------------------------+
1660 ! THIS FUNCTION CALCULATES THE LIQUID SATURATION VAPOR MIXING RATIO AS
1661 ! A FUNCTION OF TEMPERATURE AND PRESSURE
1663       REAL FUNCTION RSLF(P,T)
1665       IMPLICIT NONE
1666       REAL, INTENT(IN):: P, T
1667       REAL:: ESL,X
1668       REAL, PARAMETER:: C0= .611583699E03
1669       REAL, PARAMETER:: C1= .444606896E02
1670       REAL, PARAMETER:: C2= .143177157E01
1671       REAL, PARAMETER:: C3= .264224321E-1
1672       REAL, PARAMETER:: C4= .299291081E-3
1673       REAL, PARAMETER:: C5= .203154182E-5
1674       REAL, PARAMETER:: C6= .702620698E-8
1675       REAL, PARAMETER:: C7= .379534310E-11
1676       REAL, PARAMETER:: C8=-.321582393E-13
1678       X=MAX(-80.,T-273.16)
1680 !      ESL=612.2*EXP(17.67*X/(T-29.65))
1681       ESL=C0+X*(C1+X*(C2+X*(C3+X*(C4+X*(C5+X*(C6+X*(C7+X*C8)))))))
1682       RSLF=.622*ESL/(P-ESL)
1684       END FUNCTION RSLF
1686 !+---+-----------------------------------------------------------------+
1687 ! THIS FUNCTION CALCULATES THE ICE SATURATION VAPOR MIXING RATIO AS A
1688 ! FUNCTION OF TEMPERATURE AND PRESSURE
1690       REAL FUNCTION RSIF(P,T)
1692       IMPLICIT NONE
1693       REAL, INTENT(IN):: P, T
1694       REAL:: ESI,X
1695       REAL, PARAMETER:: C0= .609868993E03
1696       REAL, PARAMETER:: C1= .499320233E02
1697       REAL, PARAMETER:: C2= .184672631E01
1698       REAL, PARAMETER:: C3= .402737184E-1
1699       REAL, PARAMETER:: C4= .565392987E-3
1700       REAL, PARAMETER:: C5= .521693933E-5
1701       REAL, PARAMETER:: C6= .307839583E-7
1702       REAL, PARAMETER:: C7= .105785160E-9
1703       REAL, PARAMETER:: C8= .161444444E-12
1705       X=MAX(-80.,T-273.16)
1706       ESI=C0+X*(C1+X*(C2+X*(C3+X*(C4+X*(C5+X*(C6+X*(C7+X*C8)))))))
1707       RSIF=.622*ESI/(P-ESI)
1709       END FUNCTION RSIF
1710 !+---+-----------------------------------------------------------------+
1712 !----------------------------------------------------------------
1713       REAL FUNCTION ggamma(X)
1714 !----------------------------------------------------------------
1715       IMPLICIT NONE
1716 !----------------------------------------------------------------
1717       REAL, INTENT(IN   ) :: x
1718       REAL, DIMENSION(8)  :: B
1719       INTEGER             ::j, K1
1720       REAL                ::PF, G1TO2 ,TEMP
1722       DATA B/-.577191652,.988205891,-.897056937,.918206857,  &
1723              -.756704078,.482199394,-.193527818,.035868343/
1725       PF=1.
1726       TEMP=X
1727       DO 10 J=1,200
1728       IF (TEMP .LE. 2) GO TO 20
1729       TEMP=TEMP-1.
1730    10 PF=PF*TEMP
1731 !  100 FORMAT(//,5X,'module_mp_lin: INPUT TO GAMMA FUNCTION TOO LARGE, X=',E12.5)
1732 !      WRITE(wrf_err_message,100)X
1733 !      CALL wrf_error_fatal(wrf_err_message)
1734    20 G1TO2=1.
1735       TEMP=TEMP - 1.
1736       DO 30 K1=1,8
1737    30 G1TO2=G1TO2 + B(K1)*TEMP**K1
1738       ggamma=PF*G1TO2
1740       END FUNCTION ggamma
1742 !----------------------------------------------------------------
1744       END MODULE module_mp_sbu_ylin