1 | ! $Header$ |
---|
2 | |
---|
3 | ! ====================================================================== |
---|
4 | SUBROUTINE nonlocal(knon, paprs, pplay, tsol, beta, u, v, t, q, cd_h, cd_m, & |
---|
5 | pcfh, pcfm, cgh, cgq) |
---|
6 | USE dimphy |
---|
7 | USE lmdz_yoethf |
---|
8 | |
---|
9 | USE lmdz_yomcst |
---|
10 | |
---|
11 | IMPLICIT NONE |
---|
12 | INCLUDE "FCTTRE.h" |
---|
13 | ! ====================================================================== |
---|
14 | ! Laurent Li (LMD/CNRS), le 30 septembre 1998 |
---|
15 | ! Couche limite non-locale. Adaptation du code du CCM3. |
---|
16 | ! Code non teste, donc a ne pas utiliser. |
---|
17 | ! ====================================================================== |
---|
18 | ! Nonlocal scheme that determines eddy diffusivities based on a |
---|
19 | ! diagnosed boundary layer height and a turbulent velocity scale. |
---|
20 | ! Also countergradient effects for heat and moisture are included. |
---|
21 | |
---|
22 | ! For more information, see Holtslag, A.A.M., and B.A. Boville, 1993: |
---|
23 | ! Local versus nonlocal boundary-layer diffusion in a global climate |
---|
24 | ! model. J. of Climate, vol. 6, 1825-1842. |
---|
25 | ! ====================================================================== |
---|
26 | |
---|
27 | ! Arguments: |
---|
28 | |
---|
29 | INTEGER knon ! nombre de points a calculer |
---|
30 | REAL tsol(klon) ! temperature du sol (K) |
---|
31 | REAL beta(klon) ! efficacite d'evaporation (entre 0 et 1) |
---|
32 | REAL paprs(klon, klev + 1) ! pression a inter-couche (Pa) |
---|
33 | REAL pplay(klon, klev) ! pression au milieu de couche (Pa) |
---|
34 | REAL u(klon, klev) ! vitesse U (m/s) |
---|
35 | REAL v(klon, klev) ! vitesse V (m/s) |
---|
36 | REAL t(klon, klev) ! temperature (K) |
---|
37 | REAL q(klon, klev) ! vapeur d'eau (kg/kg) |
---|
38 | REAL cd_h(klon) ! coefficient de friction au sol pour chaleur |
---|
39 | REAL cd_m(klon) ! coefficient de friction au sol pour vitesse |
---|
40 | |
---|
41 | INTEGER isommet |
---|
42 | REAL vk |
---|
43 | PARAMETER (vk = 0.40) |
---|
44 | REAL ricr |
---|
45 | PARAMETER (ricr = 0.4) |
---|
46 | REAL fak |
---|
47 | PARAMETER (fak = 8.5) |
---|
48 | REAL fakn |
---|
49 | PARAMETER (fakn = 7.2) |
---|
50 | REAL onet |
---|
51 | PARAMETER (onet = 1.0 / 3.0) |
---|
52 | REAL t_coup |
---|
53 | PARAMETER (t_coup = 273.15) |
---|
54 | REAL zkmin |
---|
55 | PARAMETER (zkmin = 0.01) |
---|
56 | REAL betam |
---|
57 | PARAMETER (betam = 15.0) |
---|
58 | REAL betah |
---|
59 | PARAMETER (betah = 15.0) |
---|
60 | REAL betas |
---|
61 | PARAMETER (betas = 5.0) |
---|
62 | REAL sffrac |
---|
63 | PARAMETER (sffrac = 0.1) |
---|
64 | REAL binm |
---|
65 | PARAMETER (binm = betam * sffrac) |
---|
66 | REAL binh |
---|
67 | PARAMETER (binh = betah * sffrac) |
---|
68 | REAL ccon |
---|
69 | PARAMETER (ccon = fak * sffrac * vk) |
---|
70 | |
---|
71 | REAL z(klon, klev) |
---|
72 | REAL pcfm(klon, klev), pcfh(klon, klev) |
---|
73 | |
---|
74 | INTEGER i, k |
---|
75 | REAL zxt, zxq, zxu, zxv, zxmod, taux, tauy |
---|
76 | REAL zx_alf1, zx_alf2 ! parametres pour extrapolation |
---|
77 | REAL khfs(klon) ! surface kinematic heat flux [mK/s] |
---|
78 | REAL kqfs(klon) ! sfc kinematic constituent flux [m/s] |
---|
79 | REAL heatv(klon) ! surface virtual heat flux |
---|
80 | REAL ustar(klon) |
---|
81 | REAL rino(klon, klev) ! bulk Richardon no. from level to ref lev |
---|
82 | LOGICAL unstbl(klon) ! pts w/unstbl pbl (positive virtual ht flx) |
---|
83 | LOGICAL stblev(klon) ! stable pbl with levels within pbl |
---|
84 | LOGICAL unslev(klon) ! unstbl pbl with levels within pbl |
---|
85 | LOGICAL unssrf(klon) ! unstb pbl w/lvls within srf pbl lyr |
---|
86 | LOGICAL unsout(klon) ! unstb pbl w/lvls in outer pbl lyr |
---|
87 | LOGICAL check(klon) ! True=>chk if Richardson no.>critcal |
---|
88 | REAL pblh(klon) |
---|
89 | REAL cgh(klon, 2:klev) ! counter-gradient term for heat [K/m] |
---|
90 | REAL cgq(klon, 2:klev) ! counter-gradient term for constituents |
---|
91 | REAL cgs(klon, 2:klev) ! counter-gradient star (cg/flux) |
---|
92 | REAL obklen(klon) |
---|
93 | REAL ztvd, ztvu, zdu2 |
---|
94 | REAL therm(klon) ! thermal virtual temperature excess |
---|
95 | REAL phiminv(klon) ! inverse phi function for momentum |
---|
96 | REAL phihinv(klon) ! inverse phi function for heat |
---|
97 | REAL wm(klon) ! turbulent velocity scale for momentum |
---|
98 | REAL fak1(klon) ! k*ustar*pblh |
---|
99 | REAL fak2(klon) ! k*wm*pblh |
---|
100 | REAL fak3(klon) ! fakn*wstr/wm |
---|
101 | REAL pblk(klon) ! level eddy diffusivity for momentum |
---|
102 | REAL pr(klon) ! Prandtl number for eddy diffusivities |
---|
103 | REAL zl(klon) ! zmzp / Obukhov length |
---|
104 | REAL zh(klon) ! zmzp / pblh |
---|
105 | REAL zzh(klon) ! (1-(zmzp/pblh))**2 |
---|
106 | REAL wstr(klon) ! w*, convective velocity scale |
---|
107 | REAL zm(klon) ! current level height |
---|
108 | REAL zp(klon) ! current level height + one level up |
---|
109 | REAL zcor, zdelta, zcvm5, zxqs |
---|
110 | REAL fac, pblmin, zmzp, term |
---|
111 | |
---|
112 | ! Initialisation |
---|
113 | |
---|
114 | isommet = klev |
---|
115 | |
---|
116 | DO i = 1, klon |
---|
117 | pcfh(i, 1) = cd_h(i) |
---|
118 | pcfm(i, 1) = cd_m(i) |
---|
119 | END DO |
---|
120 | DO k = 2, klev |
---|
121 | DO i = 1, klon |
---|
122 | pcfh(i, k) = zkmin |
---|
123 | pcfm(i, k) = zkmin |
---|
124 | cgs(i, k) = 0.0 |
---|
125 | cgh(i, k) = 0.0 |
---|
126 | cgq(i, k) = 0.0 |
---|
127 | END DO |
---|
128 | END DO |
---|
129 | |
---|
130 | ! Calculer les hauteurs de chaque couche |
---|
131 | |
---|
132 | DO i = 1, knon |
---|
133 | z(i, 1) = rd * t(i, 1) / (0.5 * (paprs(i, 1) + pplay(i, 1))) * (paprs(i, 1) - pplay(i, 1) & |
---|
134 | ) / rg |
---|
135 | END DO |
---|
136 | DO k = 2, klev |
---|
137 | DO i = 1, knon |
---|
138 | z(i, k) = z(i, k - 1) + rd * 0.5 * (t(i, k - 1) + t(i, k)) / paprs(i, k) * (pplay(i, k - 1 & |
---|
139 | ) - pplay(i, k)) / rg |
---|
140 | END DO |
---|
141 | END DO |
---|
142 | |
---|
143 | DO i = 1, knon |
---|
144 | IF (thermcep) THEN |
---|
145 | zdelta = max(0., sign(1., rtt - tsol(i))) |
---|
146 | zcvm5 = r5les * rlvtt * (1. - zdelta) + r5ies * rlstt * zdelta |
---|
147 | zcvm5 = zcvm5 / rcpd / (1.0 + rvtmp2 * q(i, 1)) |
---|
148 | zxqs = r2es * foeew(tsol(i), zdelta) / paprs(i, 1) |
---|
149 | zxqs = min(0.5, zxqs) |
---|
150 | zcor = 1. / (1. - retv * zxqs) |
---|
151 | zxqs = zxqs * zcor |
---|
152 | ELSE |
---|
153 | IF (tsol(i)<t_coup) THEN |
---|
154 | zxqs = qsats(tsol(i)) / paprs(i, 1) |
---|
155 | ELSE |
---|
156 | zxqs = qsatl(tsol(i)) / paprs(i, 1) |
---|
157 | END IF |
---|
158 | END IF |
---|
159 | zx_alf1 = 1.0 |
---|
160 | zx_alf2 = 1.0 - zx_alf1 |
---|
161 | zxt = (t(i, 1) + z(i, 1) * rg / rcpd / (1. + rvtmp2 * q(i, 1))) * (1. + retv * q(i, 1)) * zx_alf1 & |
---|
162 | + (t(i, 2) + z(i, 2) * rg / rcpd / (1. + rvtmp2 * q(i, 2))) * (1. + retv * q(i, 2)) * zx_alf2 |
---|
163 | zxu = u(i, 1) * zx_alf1 + u(i, 2) * zx_alf2 |
---|
164 | zxv = v(i, 1) * zx_alf1 + v(i, 2) * zx_alf2 |
---|
165 | zxq = q(i, 1) * zx_alf1 + q(i, 2) * zx_alf2 |
---|
166 | zxmod = 1.0 + sqrt(zxu**2 + zxv**2) |
---|
167 | khfs(i) = (tsol(i) * (1. + retv * q(i, 1)) - zxt) * zxmod * cd_h(i) |
---|
168 | kqfs(i) = (zxqs - zxq) * zxmod * cd_h(i) * beta(i) |
---|
169 | heatv(i) = khfs(i) + 0.61 * zxt * kqfs(i) |
---|
170 | taux = zxu * zxmod * cd_m(i) |
---|
171 | tauy = zxv * zxmod * cd_m(i) |
---|
172 | ustar(i) = sqrt(taux**2 + tauy**2) |
---|
173 | ustar(i) = max(sqrt(ustar(i)), 0.01) |
---|
174 | END DO |
---|
175 | |
---|
176 | DO i = 1, knon |
---|
177 | rino(i, 1) = 0.0 |
---|
178 | check(i) = .TRUE. |
---|
179 | pblh(i) = z(i, 1) |
---|
180 | obklen(i) = -t(i, 1) * ustar(i)**3 / (rg * vk * heatv(i)) |
---|
181 | END DO |
---|
182 | |
---|
183 | |
---|
184 | ! PBL height calculation: |
---|
185 | ! Search for level of pbl. Scan upward until the Richardson number between |
---|
186 | ! the first level and the current level exceeds the "critical" value. |
---|
187 | |
---|
188 | fac = 100.0 |
---|
189 | DO k = 1, isommet |
---|
190 | DO i = 1, knon |
---|
191 | IF (check(i)) THEN |
---|
192 | zdu2 = (u(i, k) - u(i, 1))**2 + (v(i, k) - v(i, 1))**2 + fac * ustar(i)**2 |
---|
193 | zdu2 = max(zdu2, 1.0E-20) |
---|
194 | ztvd = (t(i, k) + z(i, k) * 0.5 * rg / rcpd / (1. + rvtmp2 * q(i, & |
---|
195 | k))) * (1. + retv * q(i, k)) |
---|
196 | ztvu = (t(i, 1) - z(i, k) * 0.5 * rg / rcpd / (1. + rvtmp2 * q(i, & |
---|
197 | 1))) * (1. + retv * q(i, 1)) |
---|
198 | rino(i, k) = (z(i, k) - z(i, 1)) * rg * (ztvd - ztvu) / (zdu2 * 0.5 * (ztvd + ztvu)) |
---|
199 | IF (rino(i, k)>=ricr) THEN |
---|
200 | pblh(i) = z(i, k - 1) + (z(i, k - 1) - z(i, k)) * (ricr - rino(i, k - 1)) / (rino(i, & |
---|
201 | k - 1) - rino(i, k)) |
---|
202 | check(i) = .FALSE. |
---|
203 | END IF |
---|
204 | END IF |
---|
205 | END DO |
---|
206 | END DO |
---|
207 | |
---|
208 | |
---|
209 | ! Set pbl height to maximum value where computation exceeds number of |
---|
210 | ! layers allowed |
---|
211 | |
---|
212 | DO i = 1, knon |
---|
213 | IF (check(i)) pblh(i) = z(i, isommet) |
---|
214 | END DO |
---|
215 | |
---|
216 | ! Improve estimate of pbl height for the unstable points. |
---|
217 | ! Find unstable points (sensible heat flux is upward): |
---|
218 | |
---|
219 | DO i = 1, knon |
---|
220 | IF (heatv(i)>0.) THEN |
---|
221 | unstbl(i) = .TRUE. |
---|
222 | check(i) = .TRUE. |
---|
223 | ELSE |
---|
224 | unstbl(i) = .FALSE. |
---|
225 | check(i) = .FALSE. |
---|
226 | END IF |
---|
227 | END DO |
---|
228 | |
---|
229 | ! For the unstable case, compute velocity scale and the |
---|
230 | ! convective temperature excess: |
---|
231 | |
---|
232 | DO i = 1, knon |
---|
233 | IF (check(i)) THEN |
---|
234 | phiminv(i) = (1. - binm * pblh(i) / obklen(i))**onet |
---|
235 | wm(i) = ustar(i) * phiminv(i) |
---|
236 | therm(i) = heatv(i) * fak / wm(i) |
---|
237 | rino(i, 1) = 0.0 |
---|
238 | END IF |
---|
239 | END DO |
---|
240 | |
---|
241 | ! Improve pblh estimate for unstable conditions using the |
---|
242 | ! convective temperature excess: |
---|
243 | |
---|
244 | DO k = 1, isommet |
---|
245 | DO i = 1, knon |
---|
246 | IF (check(i)) THEN |
---|
247 | zdu2 = (u(i, k) - u(i, 1))**2 + (v(i, k) - v(i, 1))**2 + fac * ustar(i)**2 |
---|
248 | zdu2 = max(zdu2, 1.0E-20) |
---|
249 | ztvd = (t(i, k) + z(i, k) * 0.5 * rg / rcpd / (1. + rvtmp2 * q(i, & |
---|
250 | k))) * (1. + retv * q(i, k)) |
---|
251 | ztvu = (t(i, 1) + therm(i) - z(i, k) * 0.5 * rg / rcpd / (1. + rvtmp2 * q(i, & |
---|
252 | 1))) * (1. + retv * q(i, 1)) |
---|
253 | rino(i, k) = (z(i, k) - z(i, 1)) * rg * (ztvd - ztvu) / (zdu2 * 0.5 * (ztvd + ztvu)) |
---|
254 | IF (rino(i, k)>=ricr) THEN |
---|
255 | pblh(i) = z(i, k - 1) + (z(i, k - 1) - z(i, k)) * (ricr - rino(i, k - 1)) / (rino(i, & |
---|
256 | k - 1) - rino(i, k)) |
---|
257 | check(i) = .FALSE. |
---|
258 | END IF |
---|
259 | END IF |
---|
260 | END DO |
---|
261 | END DO |
---|
262 | |
---|
263 | ! Set pbl height to maximum value where computation exceeds number of |
---|
264 | ! layers allowed |
---|
265 | |
---|
266 | DO i = 1, knon |
---|
267 | IF (check(i)) pblh(i) = z(i, isommet) |
---|
268 | END DO |
---|
269 | |
---|
270 | ! Points for which pblh exceeds number of pbl layers allowed; |
---|
271 | ! set to maximum |
---|
272 | |
---|
273 | DO i = 1, knon |
---|
274 | IF (check(i)) pblh(i) = z(i, isommet) |
---|
275 | END DO |
---|
276 | |
---|
277 | ! PBL height must be greater than some minimum mechanical mixing depth |
---|
278 | ! Several investigators have proposed minimum mechanical mixing depth |
---|
279 | ! relationships as a function of the local friction velocity, u*. We |
---|
280 | ! make use of a linear relationship of the form h = c u* where c=700. |
---|
281 | ! The scaling arguments that give rise to this relationship most often |
---|
282 | ! represent the coefficient c as some constant over the local coriolis |
---|
283 | ! parameter. Here we make use of the experimental results of Koracin |
---|
284 | ! and Berkowicz (1988) [BLM, Vol 43] for wich they recommend 0.07/f |
---|
285 | ! where f was evaluated at 39.5 N and 52 N. Thus we use a typical mid |
---|
286 | ! latitude value for f so that c = 0.07/f = 700. |
---|
287 | |
---|
288 | DO i = 1, knon |
---|
289 | pblmin = 700.0 * ustar(i) |
---|
290 | pblh(i) = max(pblh(i), pblmin) |
---|
291 | END DO |
---|
292 | |
---|
293 | ! pblh is now available; do preparation for diffusivity calculation: |
---|
294 | |
---|
295 | DO i = 1, knon |
---|
296 | pblk(i) = 0.0 |
---|
297 | fak1(i) = ustar(i) * pblh(i) * vk |
---|
298 | |
---|
299 | ! Do additional preparation for unstable cases only, set temperature |
---|
300 | ! and moisture perturbations depending on stability. |
---|
301 | |
---|
302 | IF (unstbl(i)) THEN |
---|
303 | zxt = (t(i, 1) - z(i, 1) * 0.5 * rg / rcpd / (1. + rvtmp2 * q(i, 1))) * (1. + retv * q(i, 1)) |
---|
304 | phiminv(i) = (1. - binm * pblh(i) / obklen(i))**onet |
---|
305 | phihinv(i) = sqrt(1. - binh * pblh(i) / obklen(i)) |
---|
306 | wm(i) = ustar(i) * phiminv(i) |
---|
307 | fak2(i) = wm(i) * pblh(i) * vk |
---|
308 | wstr(i) = (heatv(i) * rg * pblh(i) / zxt)**onet |
---|
309 | fak3(i) = fakn * wstr(i) / wm(i) |
---|
310 | END IF |
---|
311 | END DO |
---|
312 | |
---|
313 | ! Main level loop to compute the diffusivities and |
---|
314 | ! counter-gradient terms: |
---|
315 | |
---|
316 | DO k = 2, isommet |
---|
317 | |
---|
318 | ! Find levels within boundary layer: |
---|
319 | |
---|
320 | DO i = 1, knon |
---|
321 | unslev(i) = .FALSE. |
---|
322 | stblev(i) = .FALSE. |
---|
323 | zm(i) = z(i, k - 1) |
---|
324 | zp(i) = z(i, k) |
---|
325 | IF (zkmin==0.0 .AND. zp(i)>pblh(i)) zp(i) = pblh(i) |
---|
326 | IF (zm(i)<pblh(i)) THEN |
---|
327 | zmzp = 0.5 * (zm(i) + zp(i)) |
---|
328 | zh(i) = zmzp / pblh(i) |
---|
329 | zl(i) = zmzp / obklen(i) |
---|
330 | zzh(i) = 0. |
---|
331 | IF (zh(i)<=1.0) zzh(i) = (1. - zh(i))**2 |
---|
332 | |
---|
333 | ! stblev for points zm < plbh and stable and neutral |
---|
334 | ! unslev for points zm < plbh and unstable |
---|
335 | |
---|
336 | IF (unstbl(i)) THEN |
---|
337 | unslev(i) = .TRUE. |
---|
338 | ELSE |
---|
339 | stblev(i) = .TRUE. |
---|
340 | END IF |
---|
341 | END IF |
---|
342 | END DO |
---|
343 | |
---|
344 | ! Stable and neutral points; set diffusivities; counter-gradient |
---|
345 | ! terms zero for stable case: |
---|
346 | |
---|
347 | DO i = 1, knon |
---|
348 | IF (stblev(i)) THEN |
---|
349 | IF (zl(i)<=1.) THEN |
---|
350 | pblk(i) = fak1(i) * zh(i) * zzh(i) / (1. + betas * zl(i)) |
---|
351 | ELSE |
---|
352 | pblk(i) = fak1(i) * zh(i) * zzh(i) / (betas + zl(i)) |
---|
353 | END IF |
---|
354 | pcfm(i, k) = pblk(i) |
---|
355 | pcfh(i, k) = pcfm(i, k) |
---|
356 | END IF |
---|
357 | END DO |
---|
358 | |
---|
359 | ! unssrf, unstable within surface layer of pbl |
---|
360 | ! unsout, unstable within outer layer of pbl |
---|
361 | |
---|
362 | DO i = 1, knon |
---|
363 | unssrf(i) = .FALSE. |
---|
364 | unsout(i) = .FALSE. |
---|
365 | IF (unslev(i)) THEN |
---|
366 | IF (zh(i)<sffrac) THEN |
---|
367 | unssrf(i) = .TRUE. |
---|
368 | ELSE |
---|
369 | unsout(i) = .TRUE. |
---|
370 | END IF |
---|
371 | END IF |
---|
372 | END DO |
---|
373 | |
---|
374 | ! Unstable for surface layer; counter-gradient terms zero |
---|
375 | |
---|
376 | DO i = 1, knon |
---|
377 | IF (unssrf(i)) THEN |
---|
378 | term = (1. - betam * zl(i))**onet |
---|
379 | pblk(i) = fak1(i) * zh(i) * zzh(i) * term |
---|
380 | pr(i) = term / sqrt(1. - betah * zl(i)) |
---|
381 | END IF |
---|
382 | END DO |
---|
383 | |
---|
384 | ! Unstable for outer layer; counter-gradient terms non-zero: |
---|
385 | |
---|
386 | DO i = 1, knon |
---|
387 | IF (unsout(i)) THEN |
---|
388 | pblk(i) = fak2(i) * zh(i) * zzh(i) |
---|
389 | cgs(i, k) = fak3(i) / (pblh(i) * wm(i)) |
---|
390 | cgh(i, k) = khfs(i) * cgs(i, k) |
---|
391 | pr(i) = phiminv(i) / phihinv(i) + ccon * fak3(i) / fak |
---|
392 | cgq(i, k) = kqfs(i) * cgs(i, k) |
---|
393 | END IF |
---|
394 | END DO |
---|
395 | |
---|
396 | ! For all unstable layers, set diffusivities |
---|
397 | |
---|
398 | DO i = 1, knon |
---|
399 | IF (unslev(i)) THEN |
---|
400 | pcfm(i, k) = pblk(i) |
---|
401 | pcfh(i, k) = pblk(i) / pr(i) |
---|
402 | END IF |
---|
403 | END DO |
---|
404 | END DO ! end of level loop |
---|
405 | |
---|
406 | END SUBROUTINE nonlocal |
---|