-
Notifications
You must be signed in to change notification settings - Fork 24
/
Copy pathisoneutral_jax.py
298 lines (270 loc) · 8.63 KB
/
isoneutral_jax.py
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
import jax
import jax.numpy as jnp
@jax.jit
def get_drhodT(salt, temp, p):
rho0 = 1024.0
z0 = 0.0
theta0 = 283.0 - 273.15
grav = 9.81
betaT = 1.67e-4
betaTs = 1e-5
gammas = 1.1e-8
zz = -p - z0
thetas = temp - theta0
return -(betaTs * thetas + betaT * (1 - gammas * grav * zz * rho0)) * rho0
@jax.jit
def get_drhodS(salt, temp, p):
betaS = 0.78e-3
rho0 = 1024.0
return betaS * rho0 * jnp.ones_like(temp)
@jax.jit
def isoneutral_diffusion_pre(
maskT,
maskU,
maskV,
maskW,
dxt,
dxu,
dyt,
dyu,
dzt,
dzw,
cost,
cosu,
salt,
temp,
zt,
K_iso,
K_11,
K_22,
K_33,
Ai_ez,
Ai_nz,
Ai_bx,
Ai_by,
):
"""
Isopycnal diffusion for tracer
following functional formulation by Griffies et al
Code adopted from MOM2.1
"""
epsln = 1e-20
iso_slopec = 1e-3
iso_dslope = 1e-3
K_iso_steep = 50.0
tau = 0
dTdx = jnp.zeros_like(K_11)
dSdx = jnp.zeros_like(K_11)
dTdy = jnp.zeros_like(K_11)
dSdy = jnp.zeros_like(K_11)
dTdz = jnp.zeros_like(K_11)
dSdz = jnp.zeros_like(K_11)
"""
drho_dt and drho_ds at centers of T cells
"""
drdT = maskT * get_drhodT(salt[:, :, :, tau], temp[:, :, :, tau], jnp.abs(zt))
drdS = maskT * get_drhodS(salt[:, :, :, tau], temp[:, :, :, tau], jnp.abs(zt))
"""
gradients at top face of T cells
"""
dTdz = dTdz.at[:, :, :-1].set(
maskW[:, :, :-1]
* (temp[:, :, 1:, tau] - temp[:, :, :-1, tau])
/ dzw[jnp.newaxis, jnp.newaxis, :-1],
)
dSdz = dSdz.at[:, :, :-1].set(
maskW[:, :, :-1]
* (salt[:, :, 1:, tau] - salt[:, :, :-1, tau])
/ dzw[jnp.newaxis, jnp.newaxis, :-1],
)
"""
gradients at eastern face of T cells
"""
dTdx = dTdx.at[:-1, :, :].set(
maskU[:-1, :, :]
* (temp[1:, :, :, tau] - temp[:-1, :, :, tau])
/ (dxu[:-1, jnp.newaxis, jnp.newaxis] * cost[jnp.newaxis, :, jnp.newaxis]),
)
dSdx = dSdx.at[:-1, :, :].set(
maskU[:-1, :, :]
* (salt[1:, :, :, tau] - salt[:-1, :, :, tau])
/ (dxu[:-1, jnp.newaxis, jnp.newaxis] * cost[jnp.newaxis, :, jnp.newaxis]),
)
"""
gradients at northern face of T cells
"""
dTdy = dTdy.at[:, :-1, :].set(
maskV[:, :-1, :]
* (temp[:, 1:, :, tau] - temp[:, :-1, :, tau])
/ dyu[jnp.newaxis, :-1, jnp.newaxis],
)
dSdy = dSdy.at[:, :-1, :].set(
maskV[:, :-1, :]
* (salt[:, 1:, :, tau] - salt[:, :-1, :, tau])
/ dyu[jnp.newaxis, :-1, jnp.newaxis],
)
def dm_taper(sx):
"""
tapering function for isopycnal slopes
"""
return 0.5 * (1.0 + jnp.tanh((-jnp.abs(sx) + iso_slopec) / iso_dslope))
"""
Compute Ai_ez and K11 on center of east face of T cell.
"""
diffloc = jnp.zeros_like(K_11)
diffloc = diffloc.at[1:-2, 2:-2, 1:].set(
0.25
* (
K_iso[1:-2, 2:-2, 1:]
+ K_iso[1:-2, 2:-2, :-1]
+ K_iso[2:-1, 2:-2, 1:]
+ K_iso[2:-1, 2:-2, :-1]
),
)
diffloc = diffloc.at[1:-2, 2:-2, 0].set(
0.5 * (K_iso[1:-2, 2:-2, 0] + K_iso[2:-1, 2:-2, 0]),
)
sumz = jnp.zeros_like(K_11)[1:-2, 2:-2]
for kr in range(2):
ki = 0 if kr == 1 else 1
for ip in range(2):
drodxe = (
drdT[1 + ip : -2 + ip, 2:-2, ki:] * dTdx[1:-2, 2:-2, ki:]
+ drdS[1 + ip : -2 + ip, 2:-2, ki:] * dSdx[1:-2, 2:-2, ki:]
)
drodze = (
drdT[1 + ip : -2 + ip, 2:-2, ki:]
* dTdz[1 + ip : -2 + ip, 2:-2, : -1 + kr or None]
+ drdS[1 + ip : -2 + ip, 2:-2, ki:]
* dSdz[1 + ip : -2 + ip, 2:-2, : -1 + kr or None]
)
sxe = -drodxe / (jnp.minimum(0.0, drodze) - epsln)
taper = dm_taper(sxe)
sumz = sumz.at[:, :, ki:].set(
sumz[..., ki:]
+ dzw[jnp.newaxis, jnp.newaxis, : -1 + kr or None]
* maskU[1:-2, 2:-2, ki:]
* jnp.maximum(K_iso_steep, diffloc[1:-2, 2:-2, ki:] * taper),
)
Ai_ez = Ai_ez.at[1:-2, 2:-2, ki:, ip, kr].set(
taper * sxe * maskU[1:-2, 2:-2, ki:],
)
K_11 = K_11.at[1:-2, 2:-2, :].set(
sumz / (4.0 * dzt[jnp.newaxis, jnp.newaxis, :]),
)
"""
Compute Ai_nz and K_22 on center of north face of T cell.
"""
diffloc = diffloc.at[...].set( 0)
diffloc = diffloc.at[2:-2, 1:-2, 1:].set(
0.25
* (
K_iso[2:-2, 1:-2, 1:]
+ K_iso[2:-2, 1:-2, :-1]
+ K_iso[2:-2, 2:-1, 1:]
+ K_iso[2:-2, 2:-1, :-1]
),
)
diffloc = diffloc.at[2:-2, 1:-2, 0].set(
0.5 * (K_iso[2:-2, 1:-2, 0] + K_iso[2:-2, 2:-1, 0]),
)
sumz = jnp.zeros_like(K_11)[2:-2, 1:-2]
for kr in range(2):
ki = 0 if kr == 1 else 1
for jp in range(2):
drodyn = (
drdT[2:-2, 1 + jp : -2 + jp, ki:] * dTdy[2:-2, 1:-2, ki:]
+ drdS[2:-2, 1 + jp : -2 + jp, ki:] * dSdy[2:-2, 1:-2, ki:]
)
drodzn = (
drdT[2:-2, 1 + jp : -2 + jp, ki:]
* dTdz[2:-2, 1 + jp : -2 + jp, : -1 + kr or None]
+ drdS[2:-2, 1 + jp : -2 + jp, ki:]
* dSdz[2:-2, 1 + jp : -2 + jp, : -1 + kr or None]
)
syn = -drodyn / (jnp.minimum(0.0, drodzn) - epsln)
taper = dm_taper(syn)
sumz = sumz.at[:, :, ki:].set(
sumz[..., ki:]
+ dzw[jnp.newaxis, jnp.newaxis, : -1 + kr or None]
* maskV[2:-2, 1:-2, ki:]
* jnp.maximum(K_iso_steep, diffloc[2:-2, 1:-2, ki:] * taper),
)
Ai_nz = Ai_nz.at[2:-2, 1:-2, ki:, jp, kr].set(
taper * syn * maskV[2:-2, 1:-2, ki:],
)
K_22 = K_22.at[2:-2, 1:-2, :].set(
sumz / (4.0 * dzt[jnp.newaxis, jnp.newaxis, :]),
)
"""
compute Ai_bx, Ai_by and K33 on top face of T cell.
"""
sumx = jnp.zeros_like(K_11)[2:-2, 2:-2, :-1]
sumy = jnp.zeros_like(K_11)[2:-2, 2:-2, :-1]
for kr in range(2):
drodzb = (
drdT[2:-2, 2:-2, kr : -1 + kr or None] * dTdz[2:-2, 2:-2, :-1]
+ drdS[2:-2, 2:-2, kr : -1 + kr or None] * dSdz[2:-2, 2:-2, :-1]
)
# eastward slopes at the top of T cells
for ip in range(2):
drodxb = (
drdT[2:-2, 2:-2, kr : -1 + kr or None]
* dTdx[1 + ip : -3 + ip, 2:-2, kr : -1 + kr or None]
+ drdS[2:-2, 2:-2, kr : -1 + kr or None]
* dSdx[1 + ip : -3 + ip, 2:-2, kr : -1 + kr or None]
)
sxb = -drodxb / (jnp.minimum(0.0, drodzb) - epsln)
taper = dm_taper(sxb)
sumx += (
dxu[1 + ip : -3 + ip, jnp.newaxis, jnp.newaxis]
* K_iso[2:-2, 2:-2, :-1]
* taper
* sxb ** 2
* maskW[2:-2, 2:-2, :-1]
)
Ai_bx = Ai_bx.at[2:-2, 2:-2, :-1, ip, kr].set(
taper * sxb * maskW[2:-2, 2:-2, :-1],
)
# northward slopes at the top of T cells
for jp in range(2):
facty = cosu[1 + jp : -3 + jp] * dyu[1 + jp : -3 + jp]
drodyb = (
drdT[2:-2, 2:-2, kr : -1 + kr or None]
* dTdy[2:-2, 1 + jp : -3 + jp, kr : -1 + kr or None]
+ drdS[2:-2, 2:-2, kr : -1 + kr or None]
* dSdy[2:-2, 1 + jp : -3 + jp, kr : -1 + kr or None]
)
syb = -drodyb / (jnp.minimum(0.0, drodzb) - epsln)
taper = dm_taper(syb)
sumy += (
facty[jnp.newaxis, :, jnp.newaxis]
* K_iso[2:-2, 2:-2, :-1]
* taper
* syb ** 2
* maskW[2:-2, 2:-2, :-1]
)
Ai_by = Ai_by.at[2:-2, 2:-2, :-1, jp, kr].set(
taper * syb * maskW[2:-2, 2:-2, :-1],
)
K_33 = K_33.at[2:-2, 2:-2, :-1].set(
sumx / (4 * dxt[2:-2, jnp.newaxis, jnp.newaxis])
+ sumy
/ (
4
* dyt[jnp.newaxis, 2:-2, jnp.newaxis]
* cost[jnp.newaxis, 2:-2, jnp.newaxis]
),
)
K_33 = K_33.at[2:-2, 2:-2, -1].set( 0.0)
return K_11, K_22, K_33, Ai_ez, Ai_nz, Ai_bx, Ai_by
def prepare_inputs(*inputs, device):
out = [jnp.array(k) for k in inputs]
for o in out:
o.block_until_ready()
return out
def run(*inputs, device="cpu"):
outputs = isoneutral_diffusion_pre(*inputs)
for o in outputs:
o.block_until_ready()
return outputs