argon (Ar), 21atmospheric abundance, 22
Arrhenius equation, 230
assimilation, 488
autotrophic respiration, 402
A-stable, 136
asymmetry factor, 220
atmosphere vertical structure, 24–27
atmospheric chemistry model. See chemical transport model
atmospheric composition, 21–22, 54mass, 21
of dry air, 28
primary and secondary species, 54
atmospheric humidity, 28
atmospheric lifetime. See e-folding lifetime
atmospheric observing system, 438, 450using models to interpret observations, 480–483
atmospheric pressure, 27–28vertical profile, 21, 25, 31–32
atmospheric scale height. See scale height
atmospheric stability, 31–35
atmospheric temperature, 24barriers, 389–390
mesopause, 25
stratopause, 25
stratosphere, 25
at the surface, 21
thermopause, 25
tropopause, 25
vertical profile, 24
atmospheric tides, 50–51
atmospheric transport interhemispheric, 43
meridional mixing, 43
attenuation coefficient. See Extinction coefficient
autocorrelogram, 469
averaging kernel, 493matrix, 511–513
Avogadro’s number, 27
azimuthal angle, 571
band matrix, 499
baroclinic atmosphere, 40–41and circulation in the troposphere, 43
definition, 40
baroclinic instability, 41
barometric law, 31–32
barosphere, 27
barotropic atmosphere, 40–41definition, 40
Bayes’ theorem, 490–491Bayesian solution, 490
normalizing factor, 490
posterior pdf, 489
prior pdf, 490
Beer’s law, 81
Beer–Lambert Law, 207
Bergeron process. See precipitation
bidirectional reflectance distribution function (BRDF), 224
big-leaf model, 418
bimolecular reaction, 230–231collision frequency, 230
reaction rate, 230
binary nucleation, 245
biofixation, 405
biomass burning. See open fires
blackbody, 211radiation, 211–213
Boltzmann’s constant, 27, 211
bottom-up constraint, 488
bottom-up emission inventories, 400
boundary condition Dirichlet, 282
periodic, 282
no-slip, 105
Boussinesq approximation, 353
box model definition, 17
Brewer–Dobson circulation, 25, 50, 57
broad-band model, 226
Brownian diffusion coefficient, 246
Brunt–Väisälä frequency, 389
burning efficiency, 409
calibration, model, 437
carbon cycle, terrestrial, 403
carbon dioxide (CO2), 21atmospheric abundance, 22
greenhouse gas, 23
interhemispheric gradient, 43
carbon monoxide (CO), 68–69global distribution, 69
cascade impactors. See aerosol observations:in- situ
Cauchy momentum equation, 104
CCL. See convective cloud layer (CCL)
CCN. See cloud condensation nuclei (CCN)
central limit theorem, 495
centered root mean square error (CRMSE), 475
CFCs. See chlorofluorocarbons
CFL criterion, 288
CH4. See methane (CH4)
Chapman mechanism. 11–12, See ozone (O3), stratospheric
Chappuis band, 55, 217
characteristic timescale, 97
checkerboard noise, 527
chemical covariance, 349–351
chemical eddy transport, 127
chemical evolution equation, 232
chemical family, 56, 262, 269
chemical ionization mass spectrometry (CIMS), 439atmospheric components measured, 440–441
chemical lifetime, 98
chemical mechanism definition, 233
stiffness, 254, 262
chemical segregation, 368
chemical solvers, 54
chemical transport model, 4880-D models, 17
1-D models, 17
2-D models, 17
biogeochemical processes, 15
and the continuity equation, 5, 15
chemical mechanism, 54
data assimilation, 16
definition, 1, 15
Eulerian versus Lagrangian, 16–17, 276
field campaigns, 438
history, 1–2, 11–15
offline, 15
online, 15
chemiluminescence, 442atmospheric components measured, 440–441
chlorofluorocarbons (CFCs), 12
chromatography. See also gas chromatography (GC)definition, 439
CIMS. See chemical ionization mass spectrometry (CIMS)
Clausius–Clapeyron equation, 30and the adiabatic lapse rate, 30
climate models history, 9–11
closure. See continuity equation:closure relation
cloud condensation nuclei (CCN), 245
cloud-resolving model. See large eddy simulation (LES)
clouds formation, 24, 29, 378
in the planetary boundary layer, 49
CO2. See carbon dioxide (CO2)
coagulation, 247
coagulation coefficient, 246
compensation point, 428
complementary slackness condition, 529
compressibility, 279
computing atmospheric chemistry models, 1, 15
cluster, 19
Earth system models, 15
Fortran, 19
general circulation models, 10
grid, 19
high-performance, 4, 19–20
memory, 19
message passing interface (MPI), 19
meteorological models, 8–9
models, 4
Moore’s law, 4
node, 19–20
open multi-processing (openMP), 19
parallelization, 7, 19
power, 4, 8
processors, 19
speed, 19–20
supercomputer, 7, 19
condensation, 246
condensation growth rate, 246
condensation equation, 246
condensation, aerosol, 246
condensation nuclei counters. See aerosol observations: in-situ
conditional PDF, 490, 492
conditional stability. See stability
conductance, 429
conservation of mass, 275
conservation equation atmospheric dynamics, 102
energy. See equation of energy
momentum, 104
continuity equation aerosol, 95
anelastic, 116
box models, 17
chemical species, 85
closure relation, 343, 371
Eulerian form, 5, 277
history, 7
Lagrangian form, 17, 278
Reynolds decomposition of, 347
vertical, 367
continuum regime, 240
convection, 24, 275parameterization, 378–383
velocity scale, 350
deep, 378
convective cloud layer (CCL), 49
convective precipitation, 383
convective parameterizations and vertical motion in models, 35
convective velocity scale. See convection:velocity scale
coordinate system eta η, 121
hybrid sigma-pressure σ–p, 121
isentropic, 122
isobaric. See pressure
log-pressure, 119
pressure, 117
sigma σ, 120
Coriolis force and general circulation, 42–43
; and Rossby waves, 50
Coriolis parameter, 38and planetary-scale waves, 50
correlated k-distribution method, 226
correlativity, 276
cost function, 493, 495regularization factor γ, 516
χ2, 493
Courant number, 285–286
covariance, 582
CRMSE. See centered root mean square error (CRMSE)
crystallization relative humidity (CRH), 80
CTM. See chemical transport model
curl definition, 571
theorem, 573
cuticles, of the leaf, 422
cyclone, 38and baroclinic instability, 41, 43
Dalton’s law, 28
Damköhler number, 350
data assimilation, 488, 530–5333D-VAR, 530–531
4D-VAR, 9, 530, 533
analysis, 529
chemical, 488, 529–530
meteorological, 529
reanalyses, 529
variational. See 3D-VAR and 4D-VAR
degrees of freedom for signal, 512–515
deliquescence relative humidity (DRH), 80
denitrification, 405
deposition velocity, 416
deterministic models, 4, 6definition, 5
detrainment, 378
diabatic heating in radiative transfer, 210
DIAL. See remote sensing, active
diagnostic equation, 114
differential mobility analyzers. See aerosol observations: in-situ
diffuse-reactive parameter, 242
diffusion analytical solution, 359
coefficient, 279, 285, 289, 305, 353, 356
equation, 358
numerical, 285, 289, 315, 365, 390–394
numerical solution, 358–365alternating direction implicit (ADI), 364
Crank–Nicholson, 363
DuFort–Frankel, 360
Richardson, 360
three level, 363
timescale, 280
turbulent, 279
diffusive filter, 179
digital spatial filter, 179
dimethyl sulfide (DMS) in the PBL, 368
direct numerical simulation (DNS), 343
discrete ordinates method, 222
displacement height, 377
divergence, flux, 5, 15
divergence, 277definition, 571
of a vector field, 571
theorem, 277, 573
DOAS. See remote sensing, passive
DOFS. See degrees of freedom for signal
downdraft, 378
drag coefficient, 426
dry deposition, 416
dynamic viscosity, 105
Earth system models definition, 15
Eddington method, 223
eddy correlation, 448
eddy diffusion coefficient, 351
eddy diffusivity of heat, 371
eddy flow, 275
eddy flux. See turbulence
eddy viscosity coefficient, 371
effective temperature of the Earth, 22
of the Sun, 22
efficiency computational, 276
effective scale height, 32
e-folding lifetime, 97
eigenanalysis. See eigendecomposition
eigendecomposition, 497–498
eigenvalue, 254definition, 570
eigenvector, 570
Ekman spiral, 373
El Niño–Southern Oscillation (ENSO), 44
electron microscopy. See aerosol observations:in situ
emission, at Earth’s surface, 400anthropogenic, 412
emission factor, 400
of open fires, 408
terrestrial biogenic, 402
volcanic, 410
emissivity, 212
empirical orthogonal functions (EOFs), 460
endothermic reaction, 231
ENSO. See El Niño–Southern Oscillation (ENSO)
entrainment, 378in the planetary boundary layer, 49, 372
velocity, 373
EOFs. See empirical orthogonal functions (EOFs)
equation of motion, 107
equation of state, 27–28for dry air, 28
for moist air, 29
for water vapor, 28
error characterization of models and observations, 454
error correlation, 497matrix, 497
error covariance matrix, 497–500construction, 499–500
validity, 499
error, model, 5, 9, 15, 17–18and inverse modeling, 454, 458
coding error (“bugs”), 455
community assessments, 456
grid resolution, 455–456
model parameters, 456
noise (meteorology), 456
numerical error, 455
parameterization error, 456
tolerance, 437, 480
types, 436–437
error, observations, 454random, 454
satellite measurements, 454
systematic, 454
escape velocity, 26
ESMs. See Earth system models
Euler equation, 108
evaluation, model aerosols, 463
and data assimilation, 438
definition, 436
with linear regression, 469
satellite observations, 459–460
with scatterplots, 469
selection of observations, 458
with statistical metrics. See statistical metrics, of model skill
timescale considerations, 460
exchange velocity, 429
exobase, 27
exothermic reaction, 231
expected value operator, 491
extinction coefficient, 207
extinction of radiation, 207extinction efficiency, 219
Favre decomposition, 349
filter measurements, 439
filtering, 336
finite difference methods, 254, 281Adams–Bashforth–Moulton, 261
backward differientiation formulae. See Gear solver
backward Euler, 258–259, 268
backward scheme, 131
boundary conditions, 303
centered difference, 283
central scheme, 131
checkerboarding, 296
CHEMEQ, 265
comparison, 298
Crank–Nicholson, 259, 291
Crowley. See Lax–Wendroff
ET method. See extrapolation
explicit, 254, 257, 260, 262–263, 285
exponential approximation, 263
extrapolation, 261, 263–264
forward Euler, 257, 259, 261, 284
forward scheme, 131
fully explicit. See forward Euler
fully implicit. See backward Euler
Gear solver, 271
Heun, 292
implicit, 256, 262, 268, 270, 290
Lax, 287
Lax–Wendroff, 289
leapfrog, 295
Leith. See Lax–Wendroff
Matsuno, 291
midpoint, 260
multi-step, 261
predictor-corrector, 259, 261
quasi-steady-state approximation, 264
QUICK, 294
QUICKEST, 295
RADAU5 solver, 261
relaxation coefficient, 305
RODAS3 solver, 271
ROS2 solver, 271
Rosenbrock solver, 270
Runge–Kutta, 260, 270
semi-implicit Euler, 259
stability, 254, 256–257, 262, 271
trapezoidal scheme, 134
truncation error, 283
TWOSTEP, 266
upstream method, 293
upwind differencing. See upstream method
upwind leapfrog, 297
finite element methods, 335Chapeau function, 159
Galerkin, 335
spectral element, 335
finite volume methods, 278, 305Beam–Warming. See upwind slope
centered slope, 309
Crowley–Tremback–Bott, 32
0–322
donor cell, 307
downward slope, 309
flux correction, 311
flux limiter, 312
Fromm. See centered slope
Lagrangian, 325–328
linear piecewise, 312
minmod, 313
MPDATA, 315–316
piecewise linear, 307–308
piecewise parabolic, 319–320
PPM. See piecewise parabolic
Prather, 322–325
quadratic, 307
semi-Lagrangian, 332
SHASTA, 316–319
slope limiter, 312
superbee, 313
total variation diminishing (TVD), 311
upwind slope, 309
van Leer, 313
fixed nitrogen, 405
flexibility, 276
Flops. See computing:speed
fog deposition, 399
forecast model, 488, 530
forecast state, 488
Fortran. See computing
forward model, 487, 491linearization, 502
forward model error, 491–492covariance matrix, 499
vector, 498
Fourier number, 285
Fourier transform, 576
free molecular regime, 240
free-running model, 16
free troposphere definition, 47
layers, 390–394
and the planetary boundary layer, 47–49
frequency of radiation, 205
friction force and geostrophic flow, 40
friction velocity, 374
frontal system and baroclinic instability, 41
FTIR. See remote sensing, passive
gain factor, 493
gain matrix, 511
gas chromatography (GC), 439and mass spectrometry (GC-MS), 439
atmospheric components measured, 440–441
gas constant for air, 27
for dry air, 28, 31
for water vapor, 28
universal, 27
gas-particle equilibrium, 236–239aqueous solution, 236–238
non-aqueous solution, 236
partitioning coefficient, 237
solid particles, 238
gas-particle mass transfer equation, 241
Modeling of Atmospheric Chemistry Page 72