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Mesoscale Dynamics Yuh-Lang Lin Index More Information Cambridge University Press 978-0-521-80875-0 - Mesoscale Dynamics Yuh-Lang Lin Index More information Index absolute deep convection (anelastic), 17 momentum, 254 Edington, 604 vorticity, 255–6 finite difference, 489–96 absolutely stable, 239–40 formulas for finite difference, 514–15 absorptivity, 597 four-stream, 604 accuracy geostrophic momentum, 387–9 first-order, 492–3 governing equations, 17–20 of finite difference methods, 494 hydrostatic, 19–20 second-order, 493, 502 incompressible (shallow convection), 16–18 aerodynamic roughness, see roughness length of advection equation, 495–508 airstream boundary, 386 of derivatives, 491–5 Andes Mountains, 341, 443 one-parameter scaling, 599 anvil pseudo-incompressible, 18 leading, 333 quasi-geostrophic (QG), 153–4 outflow, 333 two-parameter scaling, 599 Appalachian Mountains, 167, 174–6 two-stream, 604 advection area ageostrophic, of geostrophic momentum, 389 negative (NA), 247 differential moisture, 416, 453 positive (PA), 247 effect (thermal), 196–8, 205–15 atmosphere equation, 113, 192, 495 baroclinic, 265 mechanism (thermal), 196–8, 205–15 barotropic, 265 mechanism (multicell storm), 279–83 clear, 598–600, 601–3 thermal, 427–8 cloudy, 600–1, 603–4 time, 111 free, 3 advective acceleration, 16–7 isothermal, 17 air-mass thunderstorm atmospheric river, 453, 471 see single-cell thunderstorm asymmetry factor, 604 ALPEX, 158 autopropagation, 336 Alps, 157–72, 443–5 analysis baroclinic multivariate, 540 atmosphere, 265 univariate, 540 instability, 7, 25, 386 objective, 539 lee wave theory, 59–60, 160–2 Barnes objective, 539–40 wave, 160–2, 379, 386, 394–401 power spectral, 520 baroclinicity, 148–50, 380 linear stability, 73 Beer–Bouger–Lambert law, 597 numerical stability, 499 Bergeron forcing, 392 approximation Bernoulli anelastic (deep convection), 17 function, 150–1 Boussinesq, 16–19, 24 theorem, 151 618 © Cambridge University Press www.cambridge.org Cambridge University Press 978-0-521-80875-0 - Mesoscale Dynamics Yuh-Lang Lin Index More information Index 619 blackbody temperature, 596 regeneration, 279–83 Boltzmann’s constant, 596 Central Mountain Range (CMR), 168–72, 443 bora (bura), 131, 159 CFL stability criterion, 499, 503 boundary layer, 315 check friction, 352 contradiction, 539 separation, 125, 145–6, 315 buddy, 539 boundary condition gross, 539 boundedness, 39, 104, 111, 186 plausible, 539 closed, 528 chinook, 131 constant gradient, 530 circulation dynamic, 52, 70, 87, 186 ageostrophic, 392–6, 408, 422–3 free-slip, 146, 537 inland see breeze, 417 interface, 52, 70, 87, 187 secondary, 392, 408, 422–3 linear, 110, 537 solenoidal, 417 nonlinear, 110, 127, 537 thermally direct, 393, 422 no-slip, 538, 568, 576 thermally indirect, 422–5 kinematic, 52, 70, 87, 186 transverse, 392, 408, 422–3, 431 lower, 70, 110, 459, 537–8 CISK, 351–2 numerical, 490–7, 528–38 closure assumptions for KF scheme, 594 numerical upper radiation, 42, 104 cloud open, see radiation boundary condition bridge, 274 periodic, 528 cold, shield, 338 radiation, 39–42, 45, 104, 529–37 comma, 360 intensity, 597 funnel, 312 longwave (terrestrial), 596 merging, 274 shortwave (solar), 596, 603–4 microphysical processes, 444 rigid lid, 531 shelf, 278 Sommerfeld, 114, 531–3 V-shaped anvil, 207–11 sponge layer, 529, 531–3 wall, 312 time-dependent, 528 coastally trapped disturbance (CTD), 173–4, 437 zero-gradient, 530 coefficient Boussinesq fluid, 19, 53 absorption, 599 bow echo, 328 drag, 573 breeze extinction, 597 land, 215–21 heat transfer, 573 lake, 215–16 wave absorption, 88–9 sea, 215–21 wave overreflection, 88–9 bright band, 201 wave reflection 52–3, 88–9 Buckingham-Å theorem, 478 wave transmission, 88–9 Burger equation, 495 cold buoyancy, 1, 239, 302 air damming, 174–6 circulation mechanism, 279, 283 air outflow, 198, 274, 283–9, 323, 334 oscillation, 1, 39, 111 core anticyclone, 340 perturbation, 19, 211 dome, 174–6 buoyancy (Brunt–Vaisala) frequency, 16, 38, 69 front aloft (CFA), 336, 411 saturated moist, 242–4, 352, 464 columnar disturbance, 130 unsaturated moist, 244, 478 confluence mechanism, 428 -gyre, 371 conservation of mass, 12 continuity equation, 12–18, 27, 61 California Coast Range, 453–4 incompressible (shallow convection), 18, 26–7 Carnot cycle (heat engine), 353 anelastic (deep convection), 17, 302, 554 processes, 353 convection, 65 CCOPE, 72, 90, 222 cellular, 472–3 cell dry, 229 closed, 229 Rayleigh–Be´nard, 229 development, 279–83 slantwise, 264, 468 growing mode, 282 upslope, 455 open, 229–30 convective propagating mode, 282 available potential energy (CAPE), 245–6, 297, propagation, 279–83 449, 455 © Cambridge University Press www.cambridge.org Cambridge University Press 978-0-521-80875-0 - Mesoscale Dynamics Yuh-Lang Lin Index More information 620 Index convective (cont.) derecho, 328 boundary layer (CBL), 221–2, 414–17, 569 development for convective systems inhibition (CIN), 243–7 downscale, 265 initiation, 413–19, 592 upscale, 265 time scale, 594 diffusivity factor, 599 convergence direct numerical simulation (DNS), 563 large-scale, 328–9 discrete broadband approach, 602 moisture, 101 dispersion, 26, 28, 40, 91–7, 128, 500 conveyor dispersion relation, 31, 40, 46, 52, 94 cold, 264 dispersive, 24–6 warm, 264 tail, 119, 128 warm, belt, 330, 434–6, 448–51 dissipation, 26 cooling kinetic energy, 564 evaporative, 12 range, 547 Newtonian, 13, 531 dissipative scale, 564 radiative, 13 divergence tendency equation, 83 coordinates downburst, 272–6 eta (step-mountain), 527 downdraft geostrophic, 391–4 compensating, 196 isentropic (), 525 forward-flank (FFD), 296, 311 isobaric, 525 rear-flank (RFD), 296–7, 311 mass (hydrostatic pressure), 527 downwelling, 538 sigma (s), 525–7 drag terrain-following( s – z), 490, 525–6 form, 35 vertical, 525–8 gravity wave, 35 s – p, 525 mountain, 35, 113 s – z, 525–6 mountain wave, 35 s – , 526 pressure, 137 cooperative intensification mechanism, 350–2 surface, 35, 131 core radius, 317–18 dryline, 380, 413–20 Courant number, 498, 508 bulge, 414 covariance, 565 formation, 417 critical primary, convergence boundary (PDCB), layer, 55–7 419–20 level, 54–60, 86, 203, 329, 414, 460 level absorption, 55 echo overhang, 295 cyclone eddy Denver, 167 diffusivity of heat, 551, 570 extratropical, 349 diffusivity of water vapor, 570 Mediterranean, 359 viscosity, 217, 362, 551, 570 parent, 160 effect passage, 451 , 22–3 cyclogenesis, 406, 411, 420–1 baroclinic, on LLJ, 435 Bernoulli (venturi), 34, 157 data assimilation, 539–47 buoyancy, 289–93 ensemble-based, 546 cold pool, 334 four-dimensional (4DDA), 539–44 corner, 157 four-dimensional variational (4DVAR), directional shear, 307–9 544–5 Fujiwhara, 370–2 three-dimensional variational (3DVAR), 543–4 nonlinear advection, 425–6 deformation rotation, 203–15 depth, 211 rotational, on mountain waves, 152–7 shear, 303 shear, 203–7, 283–9, 334 stretching, 303 three-dimensionality, 203–15 total, 241 venturi (Bernoulli) effect, 34 density effective static stability, 403 current, 64, 66, 172–4, 198–9, 334 eigenvalue, 53 also see gravity current Ekman impulse, 64–71 layer, 351, 572 perturbation, 38 layer depth, 576 © Cambridge University Press www.cambridge.org Cambridge University Press 978-0-521-80875-0 - Mesoscale Dynamics Yuh-Lang Lin Index More information Index 621 number, 176 overturning, 203 pumping, 352 potential (irrotational), 43–6, 110, 116–17, 187 spiral, 576 quasi-geostrophic, 153, 214 Eliassen and Palm theorem, 103, 113, 532 recirculation, 129 emittance, 597 rear-to-front, see rear-to-front jet energy reversal, 145 available potential, 399 secondary, 368 available buoyancy (CAPE), 247, 283, 292 splitting, 129, 146 convective available potential (CAPE), 245–6 stagnation, 145, 150 downdraft CAPE (DCAPE), 248, 292–3 subcritical, 33–7, 127–38 generation, 7–9 supercritical, 33–7, 127–38 kinetic, 33–4 transitional, 35 perturbation kinetic, 32 unbalanced, 83 perturbation potential, 32 upslope, 221 potential, 33–4, 311 wake, 152 propagation, 101–4, 119, 532 flux temperature, 570 static potential (CAPE), 247 foehn, 131, 444, 476 total perturbation, 32, 102, 231 deep, 476–7 transfer, 7–9, 24, 230–3 shallow, 476–7 wave, 197 forecasting ensemble deterministic, 556 averaging, 567–8 ensemble, 556 forecasting, 555–7 superensemble, 556–7 Kalman filter (EnKF), 547 force enthalpy Archimedean buoyancy, 241 specific, 353 buoyancy, 22–3, 43, 239 moist, 352–3 compression, 22–3 flux, 362–5 Coriolis, 9, 23 entrainment, 368 frictional (viscous), 13 entropy, 353 pressure gradient, 43, 301–3 equation of state, 13 restoring, 22–3 error growth, 556 forest fire, 229 Ethiopian Highlands (EH), 357 Fourier evanescent wave (disturbance), 22, 39, 52, 115 coefficient, 25 evaporative cooling, 30 component, 25–6 exchange coefficient transform, 79, 177–8 enthalpy, 362 frequency, 26 heat, 551, 570 Doppler-shifted (intrinsic) wave, 39, 45, 79, 217 local, 574 Intrinsic (Doppler-shifted) wave, 39, 45, 79, 217 momentum, 217, 362, 551, 570 front, 379–441 water vapor, 570 anafront, 383 explicit presentation of microphysical processes, 580 coastal, 214, 379 cold, 379–80 Fast Fourier Transform (FFT), 121 cross, circulation, 389–94 Fickian diffusion, 217 gust, 66, 198, 379 finite difference equation, 492 gust, updraft (GFU), 66, 279–83, 323–4 first law of thermodynamics, 12–16 katafront, 383 flow Mei-Yu, 171–2 blocked, 33–7, 451 mesoscale, 379–80, 405 blocking, 33–7, 129 passage, 451 confluent, 386 sea breeze, 215–21, 379 corner, 315–18 structure, 381 cyclostrophic, 303, 315–17 synoptic, 379 drainage, 221, 418 types, 379–80 front-to-rear, see front-to-rear jet upper-level,
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