tparameter-list.txt - pism - [fork] customized build of PISM, the parallel ice sheet model (tillflux branch) (HTM) git clone git://src.adamsgaard.dk/pism (DIR) Log (DIR) Files (DIR) Refs (DIR) LICENSE --- tparameter-list.txt (103957B) --- 1 .. -*- mode: rst -*- 2 3 .. DO NOT EDIT: This file was automatically generated. Edit src/pism_config.cdl instead. 4 5 6 #. :config:`age.enabled` (*flag*) 7 8 :Value: no 9 :Option: :opt:`-age` 10 :Description: Solve age equation (advection equation for ice age). 11 12 #. :config:`age.initial_value` (*number*) 13 14 :Value: 0 (years) 15 :Description: Initial age of ice 16 17 #. :config:`atmosphere.anomaly.file` (*string*) 18 19 :Value: *no default* 20 :Option: :opt:`-atmosphere_anomaly_file` 21 :Description: Name of the file containing climate forcing fields. 22 23 #. :config:`atmosphere.anomaly.period` (*integer*) 24 25 :Value: 0 26 :Option: :opt:`-atmosphere_anomaly_period` 27 :Description: Length of the period of the climate forcing data. Set to zero to disable. 28 29 #. :config:`atmosphere.anomaly.reference_year` (*integer*) 30 31 :Value: 0 32 :Option: :opt:`-atmosphere_anomaly_reference_year` 33 :Description: Reference year to use when ``atmosphere.anomaly.period`` is active. 34 35 #. :config:`atmosphere.delta_P.file` (*string*) 36 37 :Value: *no default* 38 :Option: :opt:`-atmosphere_delta_P_file` 39 :Description: Name of the file containing scalar precipitation offsets. 40 41 #. :config:`atmosphere.delta_P.period` (*integer*) 42 43 :Value: 0 44 :Option: :opt:`-atmosphere_delta_P_period` 45 :Description: Length of the period of the climate forcing data. Set to zero to disable. 46 47 #. :config:`atmosphere.delta_P.reference_year` (*integer*) 48 49 :Value: 0 50 :Option: :opt:`-atmosphere_delta_P_reference_year` 51 :Description: Reference year to use when ``atmosphere.delta_P.period`` is active. 52 53 #. :config:`atmosphere.delta_T.file` (*string*) 54 55 :Value: *no default* 56 :Option: :opt:`-atmosphere_delta_T_file` 57 :Description: Name of the file containing temperature offsets. 58 59 #. :config:`atmosphere.delta_T.period` (*integer*) 60 61 :Value: 0 62 :Option: :opt:`-atmosphere_delta_T_period` 63 :Description: Length of the period of the climate forcing data. Set to zero to disable. 64 65 #. :config:`atmosphere.delta_T.reference_year` (*integer*) 66 67 :Value: 0 68 :Option: :opt:`-atmosphere_delta_T_reference_year` 69 :Description: Reference year to use when ``atmosphere.delta_T.period`` is active. 70 71 #. :config:`atmosphere.elevation_change.file` (*string*) 72 73 :Value: *no default* 74 :Option: :opt:`-atmosphere_lapse_rate_file` 75 :Description: Name of the file containing the reference surface elevation field (variable ``usurf``). 76 77 #. :config:`atmosphere.elevation_change.period` (*integer*) 78 79 :Value: 0 80 :Option: :opt:`-atmosphere_lapse_rate_period` 81 :Description: Length of the period of the climate forcing data. Set to zero to disable. 82 83 #. :config:`atmosphere.elevation_change.precipitation.lapse_rate` (*number*) 84 85 :Value: 0 ((kg m-2 / year) / km) 86 :Option: :opt:`-precip_lapse_rate` 87 :Description: Elevation lapse rate for the surface mass balance 88 89 #. :config:`atmosphere.elevation_change.precipitation.method` (*keyword*) 90 91 :Value: ``shift`` 92 :Choices: ``scale, shift`` 93 :Option: :opt:`-precip_adjustment` 94 :Description: Choose the precipitation adjustment method. ``scale``: use temperature-change-dependent scaling factor. ``shift``: use the precipitation lapse rate. 95 96 #. :config:`atmosphere.elevation_change.reference_year` (*integer*) 97 98 :Value: 0 99 :Option: :opt:`-atmosphere_lapse_rate_reference_year` 100 :Description: Reference year to use when ``atmosphere.elevation_change.period`` is active. 101 102 #. :config:`atmosphere.elevation_change.temperature_lapse_rate` (*number*) 103 104 :Value: 0 (Kelvin / km) 105 :Option: :opt:`-temp_lapse_rate` 106 :Description: Elevation lapse rate for the surface temperature 107 108 #. :config:`atmosphere.fausto_air_temp.c_ma` (*number*) 109 110 :Value: -0.718900 (Kelvin / degree_north) 111 :Description: latitude-dependence coefficient for formula (1) in :cite:`Faustoetal2009` 112 113 #. :config:`atmosphere.fausto_air_temp.c_mj` (*number*) 114 115 :Value: -0.158500 (Kelvin / degree_north) 116 :Description: latitude-dependence coefficient for formula (2) in :cite:`Faustoetal2009` 117 118 #. :config:`atmosphere.fausto_air_temp.d_ma` (*number*) 119 120 :Value: 314.980000 (Kelvin) 121 :Description: 41.83+273.15; base temperature for formula (1) in :cite:`Faustoetal2009` 122 123 #. :config:`atmosphere.fausto_air_temp.d_mj` (*number*) 124 125 :Value: 287.850000 (Kelvin) 126 :Description: = 14.70+273.15; base temperature for formula (2) in :cite:`Faustoetal2009` 127 128 #. :config:`atmosphere.fausto_air_temp.gamma_ma` (*number*) 129 130 :Value: -0.006309 (Kelvin / meter) 131 :Description: = -6.309 / 1km; mean slope lapse rate for formula (1) in :cite:`Faustoetal2009` 132 133 #. :config:`atmosphere.fausto_air_temp.gamma_mj` (*number*) 134 135 :Value: -0.005426 (Kelvin / meter) 136 :Description: = -5.426 / 1km; mean slope lapse rate for formula (2) in :cite:`Faustoetal2009` 137 138 #. :config:`atmosphere.fausto_air_temp.kappa_ma` (*number*) 139 140 :Value: 0.067200 (Kelvin / degree_west) 141 :Description: longitude-dependence coefficient for formula (1) in :cite:`Faustoetal2009` 142 143 #. :config:`atmosphere.fausto_air_temp.kappa_mj` (*number*) 144 145 :Value: 0.051800 (Kelvin / degree_west) 146 :Description: longitude-dependence coefficient for formula (2) in :cite:`Faustoetal2009` 147 148 #. :config:`atmosphere.fausto_air_temp.summer_peak_day` (*integer*) 149 150 :Value: 196 151 :Description: day of year for July 15; used in corrected formula (4) in :cite:`Faustoetal2009` 152 153 #. :config:`atmosphere.frac_P.file` (*string*) 154 155 :Value: *no default* 156 :Option: :opt:`-atmosphere_frac_P_file` 157 :Description: Name of the file containing scalar precipitation scaling. 158 159 #. :config:`atmosphere.frac_P.period` (*integer*) 160 161 :Value: 0 162 :Option: :opt:`-atmosphere_frac_P_period` 163 :Description: Length of the period of the climate forcing data. Set to zero to disable. 164 165 #. :config:`atmosphere.frac_P.reference_year` (*integer*) 166 167 :Value: 0 168 :Option: :opt:`-atmosphere_frac_P_reference_year` 169 :Description: Reference year to use when ``atmosphere.frac_P.period`` is active. 170 171 #. :config:`atmosphere.given.file` (*string*) 172 173 :Value: *no default* 174 :Option: :opt:`-atmosphere_given_file` 175 :Description: Name of the file containing climate forcing fields. 176 177 #. :config:`atmosphere.given.period` (*integer*) 178 179 :Value: 0 180 :Option: :opt:`-atmosphere_given_period` 181 :Description: Length of the period of the climate forcing data. Set to zero to disable. 182 183 #. :config:`atmosphere.given.reference_year` (*integer*) 184 185 :Value: 0 186 :Option: :opt:`-atmosphere_given_reference_year` 187 :Description: Reference year to use when ``atmosphere.given.period`` is active. 188 189 #. :config:`atmosphere.models` (*string*) 190 191 :Value: given 192 :Option: :opt:`-atmosphere` 193 :Description: Comma-separated list of atmosphere melt models and modifiers. 194 195 #. :config:`atmosphere.one_station.file` (*string*) 196 197 :Value: *no default* 198 :Option: :opt:`-atmosphere_one_station_file` 199 :Description: Specifies a file containing scalar time-series 'precipitation' and 'air_temp'. 200 201 #. :config:`atmosphere.orographic_precipitation.background_precip_post` (*number*) 202 203 :Value: 0 (mm/hr) 204 :Option: :opt:`-background_precip_post` 205 :Description: Adding background precipitation after truncation 206 207 #. :config:`atmosphere.orographic_precipitation.background_precip_pre` (*number*) 208 209 :Value: 0 (mm/hr) 210 :Option: :opt:`-background_precip_pre` 211 :Description: Adding background precipitation before truncation 212 213 #. :config:`atmosphere.orographic_precipitation.conversion_time` (*number*) 214 215 :Value: 1000 (s) 216 :Option: :opt:`-conversion_time` 217 :Description: Cloud conversion time 218 219 #. :config:`atmosphere.orographic_precipitation.coriolis_latitude` (*number*) 220 221 :Value: 0 (degrees_N) 222 :Option: :opt:`-coriolis_latitude` 223 :Description: Latitude used to compute Coriolis force 224 225 #. :config:`atmosphere.orographic_precipitation.fallout_time` (*number*) 226 227 :Value: 1000 (s) 228 :Option: :opt:`-fallout_time` 229 :Description: Fallout time 230 231 #. :config:`atmosphere.orographic_precipitation.grid_size_factor` (*integer*) 232 233 :Value: 2 234 :Description: The spectral grid size is (Z*(grid.Mx - 1) + 1, Z*(grid.My - 1) + 1) where Z is given by this parameter. 235 236 #. :config:`atmosphere.orographic_precipitation.lapse_rate` (*number*) 237 238 :Value: -5.800000 (K / km) 239 :Option: :opt:`-lapse_rate` 240 :Description: Lapse rate 241 242 #. :config:`atmosphere.orographic_precipitation.moist_adiabatic_lapse_rate` (*number*) 243 244 :Value: -6.500000 (K / km) 245 :Option: :opt:`-moist_adiabatic_lapse_rate` 246 :Description: Water vapor scale height 247 248 #. :config:`atmosphere.orographic_precipitation.moist_stability_frequency` (*number*) 249 250 :Value: 0.050000 (1/s) 251 :Option: :opt:`-moist_stability_frequency` 252 :Description: Moist stability frequency 253 254 #. :config:`atmosphere.orographic_precipitation.reference_density` (*number*) 255 256 :Value: 0.007400 (kg m-3) 257 :Option: :opt:`-reference_density` 258 :Description: Water vapor scale height 259 260 #. :config:`atmosphere.orographic_precipitation.scale_factor` (*number*) 261 262 :Value: 1 (1) 263 :Option: :opt:`-scale_factor` 264 :Description: Precipitation scaling factor 265 266 #. :config:`atmosphere.orographic_precipitation.truncate` (*flag*) 267 268 :Value: true 269 :Option: :opt:`-truncate` 270 :Description: Truncate precipitation at 0 271 272 #. :config:`atmosphere.orographic_precipitation.water_vapor_scale_height` (*number*) 273 274 :Value: 2500 (m) 275 :Option: :opt:`-water_vapor_scale_height` 276 :Description: Water vapor scale height 277 278 #. :config:`atmosphere.orographic_precipitation.wind_direction` (*number*) 279 280 :Value: 270 (degrees) 281 :Option: :opt:`-wind_direction` 282 :Description: The direction the wind is coming from 283 284 #. :config:`atmosphere.orographic_precipitation.wind_speed` (*number*) 285 286 :Value: 10 (m/s) 287 :Option: :opt:`-wind_speed` 288 :Description: The direction the wind is coming from 289 290 #. :config:`atmosphere.pik.file` (*string*) 291 292 :Value: *no default* 293 :Option: :opt:`-atmosphere_pik_file` 294 :Description: Name of the file containing the reference surface elevation field (variable ``usurf``). 295 296 #. :config:`atmosphere.pik.parameterization` (*keyword*) 297 298 :Value: ``martin`` 299 :Choices: ``martin, huybrechts_dewolde, martin_huybrechts_dewolde, era_interim, era_interim_sin, era_interim_lon`` 300 :Option: :opt:`-atmosphere_pik` 301 :Description: Selects parameterizations of mean annual and mean summer near-surface air temperatures. 302 303 #. :config:`atmosphere.precip_exponential_factor_for_temperature` (*number*) 304 305 :Value: 0.070417 (Kelvin-1) 306 :Description: = 0.169/2.4; in SeaRISE-Greenland formula for precipitation correction using air temperature offsets relative to present; a 7.3% change of precipitation rate for every one degC of temperature change :cite:`Huybrechts02` 307 308 #. :config:`atmosphere.precip_scaling.file` (*string*) 309 310 :Value: *no default* 311 :Option: :opt:`-atmosphere_precip_scaling_file` 312 :Description: Name of the file containing temperature offsets to use for a precipitation correction. 313 314 #. :config:`atmosphere.precip_scaling.period` (*integer*) 315 316 :Value: 0 317 :Option: :opt:`-atmosphere_precip_scaling_period` 318 :Description: Length of the period of the climate forcing data. Set to zero to disable. 319 320 #. :config:`atmosphere.precip_scaling.reference_year` (*integer*) 321 322 :Value: 0 323 :Option: :opt:`-atmosphere_precip_scaling_reference_year` 324 :Description: Reference year to use when ``atmosphere.precip_scaling.period`` is active. 325 326 #. :config:`atmosphere.searise_greenland.file` (*string*) 327 328 :Value: *no default* 329 :Option: :opt:`-atmosphere_searise_greenland_file` 330 :Description: Name of the file containing a precipitation field. 331 332 #. :config:`atmosphere.uniform.precipitation` (*number*) 333 334 :Value: 1000 (kg m-2 year-1) 335 :Description: Precipitation used by the 'uniform' atmosphere model. 336 337 #. :config:`atmosphere.uniform.temperature` (*number*) 338 339 :Value: 273.150000 (Kelvin) 340 :Description: Air temperature used by the 'uniform' atmosphere model. 341 342 #. :config:`atmosphere.yearly_cycle.file` (*string*) 343 344 :Value: *no default* 345 :Option: :opt:`-atmosphere_yearly_cycle_file` 346 :Description: Name of the file containing mean annual and mean July temperatures (`air_temp_mean_annual` and `air_temp_mean_summer`) and the `precipitation` field. 347 348 #. :config:`atmosphere.yearly_cycle.scaling.file` (*string*) 349 350 :Value: *no default* 351 :Option: :opt:`-atmosphere_yearly_cycle_scaling_file` 352 :Description: Name of the file containing amplitude scaling (`amplitude_scaling`) for the near-surface air temperature. 353 354 #. :config:`atmosphere.yearly_cycle.scaling.period` (*integer*) 355 356 :Value: 0 357 :Description: Length of the period of the climate forcing data. Set to zero to disable. 358 359 #. :config:`atmosphere.yearly_cycle.scaling.reference_year` (*integer*) 360 361 :Value: 0 362 :Description: Reference year to use when ``atmosphere.yearly_cycle.scaling.period`` is active. 363 364 #. :config:`basal_resistance.beta_ice_free_bedrock` (*number*) 365 366 :Value: 1.800000e+09 (Pascal second meter-1) 367 :Description: value is for ice stream E from :cite:`HulbeMacAyeal`; thus sliding velocity, but we hope it doesn't matter much; at 100 m/year the linear sliding law gives 57040 Pa basal shear stress 368 369 #. :config:`basal_resistance.beta_lateral_margin` (*number*) 370 371 :Value: 1.000000e+19 (Pascal second meter-1) 372 :Description: high value of `\beta` used to simulate drag at lateral ice margins (fjord walls, etc); the default value is chosen to disable flow in the direction along a margin 373 374 #. :config:`basal_resistance.plastic.regularization` (*number*) 375 376 :Value: 0.010000 (meter / year) 377 :Option: :opt:`-plastic_reg` 378 :Description: Set the value of `\epsilon` regularization of plastic till; this is the second `\epsilon` in formula (4.1) in :cite:`SchoofStream` 379 380 #. :config:`basal_resistance.pseudo_plastic.enabled` (*flag*) 381 382 :Value: no 383 :Option: :opt:`-pseudo_plastic` 384 :Description: Use the pseudo-plastic till model (basal sliding law). 385 386 #. :config:`basal_resistance.pseudo_plastic.q` (*number*) 387 388 :Value: 0.250000 (pure number) 389 :Option: :opt:`-pseudo_plastic_q` 390 :Description: The exponent of the pseudo-plastic basal resistance model 391 392 #. :config:`basal_resistance.pseudo_plastic.sliding_scale_factor` (*number*) 393 394 :Value: -1 (1) 395 :Option: :opt:`-sliding_scale_factor_reduces_tauc` 396 :Description: divides pseudo-plastic tauc (yield stress) by given factor; this would increase sliding by given factor in absence of membrane stresses; not used if negative or zero; not used by default 397 398 #. :config:`basal_resistance.pseudo_plastic.u_threshold` (*number*) 399 400 :Value: 100 (meter / year) 401 :Option: :opt:`-pseudo_plastic_uthreshold` 402 :Description: threshold velocity of the pseudo-plastic sliding law 403 404 #. :config:`basal_yield_stress.add_transportable_water` (*flag*) 405 406 :Value: no 407 :Option: :opt:`-tauc_add_transportable_water` 408 :Description: If 'yes' then the water amount in the transport system is added to tillwat in determining tauc (in the Mohr-Coulomb relation). Normally only the water in the till is used. 409 410 #. :config:`basal_yield_stress.constant.value` (*number*) 411 412 :Value: 200000 (Pascal) 413 :Option: :opt:`-tauc` 414 :Description: fill value for yield stress for basal till (plastic or pseudo-plastic model); note `2 \times 10^5` Pa = 2 bar is quite strong and little sliding should occur 415 416 #. :config:`basal_yield_stress.ice_free_bedrock` (*number*) 417 418 :Value: 1000000 (Pascal) 419 :Option: :opt:`-high_tauc` 420 :Description: the 'high' yield stress value used in grounded ice-free areas. 421 422 #. :config:`basal_yield_stress.model` (*keyword*) 423 424 :Value: ``mohr_coulomb`` 425 :Choices: ``constant, mohr_coulomb`` 426 :Option: :opt:`-yield_stress` 427 :Description: The basal yield stress model to use when sliding is active. 428 429 #. :config:`basal_yield_stress.mohr_coulomb.delta.file` (*string*) 430 431 :Value: *no default* 432 :Option: :opt:`-mohr_coulomb_delta_file` 433 :Description: Name of the file containing space- and time-dependent variable `mohr_coulomb_delta` to use instead of `basal_yield_stress.mohr_coulomb.till_effective_fraction_overburden`. 434 435 #. :config:`basal_yield_stress.mohr_coulomb.delta.period` (*integer*) 436 437 :Value: 0 438 :Option: :opt:`-mohr_coulomb_delta_period` 439 :Description: Length of the period. Set to zero to disable. 440 441 #. :config:`basal_yield_stress.mohr_coulomb.delta.reference_year` (*integer*) 442 443 :Value: 0 444 :Option: :opt:`-mohr_coulomb_delta_reference_year` 445 :Description: Reference year to use when ``basal_yield_stress.mohr_coulomb.delta.period`` is active. 446 447 #. :config:`basal_yield_stress.mohr_coulomb.tauc_to_phi.file` (*string*) 448 449 :Value: *no default* 450 :Option: :opt:`-tauc_to_phi` 451 :Description: File containing the basal yield stress field that should be used to recover the till friction angle distribution. 452 453 #. :config:`basal_yield_stress.mohr_coulomb.till_cohesion` (*number*) 454 455 :Value: 0 (Pascal) 456 :Option: :opt:`-till_cohesion` 457 :Description: cohesion of till; = c_0 in most references; note Schoof uses zero but Paterson pp 168--169 gives range 0--40 kPa; but Paterson notes that '... all the pairs c_0 and phi in the table would give a yield stress for Ice Stream B that exceeds the basal shear stress there...' 458 459 #. :config:`basal_yield_stress.mohr_coulomb.till_compressibility_coefficient` (*number*) 460 461 :Value: 0.120000 (pure number) 462 :Option: :opt:`-till_compressibility_coefficient` 463 :Description: coefficient of compressiblity of till; value from :cite:`Tulaczyketal2000` 464 465 #. :config:`basal_yield_stress.mohr_coulomb.till_effective_fraction_overburden` (*number*) 466 467 :Value: 0.020000 (pure number) 468 :Option: :opt:`-till_effective_fraction_overburden` 469 :Description: `\delta` in notes; `N_0 = \delta P_o` where `P_o` is overburden pressure; `N_0` is reference (low) value of effective pressure (i.e. normal stress); `N_0` scales with overburden pressure unlike :cite:`Tulaczyketal2000`; default value from Greenland and Antarctic model runs 470 471 #. :config:`basal_yield_stress.mohr_coulomb.till_log_factor_transportable_water` (*number*) 472 473 :Value: 0.100000 (meters) 474 :Option: :opt:`-till_log_factor_transportable_water` 475 :Description: If basal_yield_stress.add_transportable_water = yes then the water amount in the transport system is added to tillwat in determining tauc. Normally only the water in the till is used. This factor multiplies the logarithm in that formula. 476 477 #. :config:`basal_yield_stress.mohr_coulomb.till_phi_default` (*number*) 478 479 :Value: 30 (degrees) 480 :Option: :opt:`-plastic_phi` 481 :Description: fill value for till friction angle 482 483 #. :config:`basal_yield_stress.mohr_coulomb.till_reference_effective_pressure` (*number*) 484 485 :Value: 1000 (Pascal) 486 :Description: reference effective pressure N_0; value from :cite:`Tulaczyketal2000` 487 488 #. :config:`basal_yield_stress.mohr_coulomb.till_reference_void_ratio` (*number*) 489 490 :Value: 0.690000 (pure number) 491 :Option: :opt:`-till_reference_void_ratio` 492 :Description: void ratio at reference effective pressure N_0; value from :cite:`Tulaczyketal2000` 493 494 #. :config:`basal_yield_stress.mohr_coulomb.topg_to_phi.enabled` (*flag*) 495 496 :Value: no 497 :Description: If the option ``-topg_to_phi`` is set then this will be set to 'yes', and then MohrCoulombYieldStress will initialize the ``tillphi`` field using a piece-wise linear function of depth described by four parameters. 498 499 #. :config:`basal_yield_stress.mohr_coulomb.topg_to_phi.phi_max` (*number*) 500 501 :Value: 15 (degrees) 502 :Description: upper value of the till friction angle; see the implementation of MohrCoulombYieldStress 503 504 #. :config:`basal_yield_stress.mohr_coulomb.topg_to_phi.phi_min` (*number*) 505 506 :Value: 5 (degrees) 507 :Description: lower value of the till friction angle; see the implementation of MohrCoulombYieldStress 508 509 #. :config:`basal_yield_stress.mohr_coulomb.topg_to_phi.topg_max` (*number*) 510 511 :Value: 1000 (meters) 512 :Description: the elevation at which the upper value of the till friction angle is used; see the implementation of MohrCoulombYieldStress 513 514 #. :config:`basal_yield_stress.mohr_coulomb.topg_to_phi.topg_min` (*number*) 515 516 :Value: -1000 (meters) 517 :Description: the elevation at which the lower value of the till friction angle is used; see the implementation of MohrCoulombYieldStress 518 519 #. :config:`basal_yield_stress.slippery_grounding_lines` (*flag*) 520 521 :Value: no 522 :Option: :opt:`-tauc_slippery_grounding_lines` 523 :Description: If yes, at icy grounded locations with bed elevations below sea level, within one cell of floating ice or ice-free ocean, make tauc as low as possible from the Mohr-Coulomb relation. Specifically, at such locations replace the normally-computed tauc from the Mohr-Coulomb relation, which uses the effective pressure from the modeled amount of water in the till, by the minimum value of tauc from Mohr-Coulomb, i.e. by using the effective pressure corresponding to the maximum amount of till-stored water. Does not alter the modeled or reported amount of till water, nor does this mechanism affect water conservation. 524 525 #. :config:`bed_deformation.bed_topography_delta_file` (*string*) 526 527 :Value: *no default* 528 :Option: :opt:`-topg_delta_file` 529 :Description: The name of the file to read the topg_delta from. This field is added to the bed topography during initialization. 530 531 #. :config:`bed_deformation.bed_uplift_file` (*string*) 532 533 :Value: *no default* 534 :Option: :opt:`-uplift_file` 535 :Description: The name of the file to read the uplift (dbdt) from. Leave empty to read it from an input file or a regridding file. 536 537 #. :config:`bed_deformation.lc.elastic_model` (*flag*) 538 539 :Value: yes 540 :Option: :opt:`-bed_def_lc_elastic_model` 541 :Description: Use the elastic part of the Lingle-Clark bed deformation model. 542 543 #. :config:`bed_deformation.lc.grid_size_factor` (*integer*) 544 545 :Value: 4 546 :Description: The spectral grid size is (Z*(grid.Mx - 1) + 1, Z*(grid.My - 1) + 1) where Z is given by this parameter. See :cite:`LingleClark`, :cite:`BLKfastearth` 547 548 #. :config:`bed_deformation.lc.update_interval` (*number*) 549 550 :Value: 10 (years) 551 :Description: Interval between updates of the Lingle-Clark model 552 553 #. :config:`bed_deformation.lithosphere_flexural_rigidity` (*number*) 554 555 :Value: 5.000000e+24 (Newton meter) 556 :Description: lithosphere flexural rigidity used by the bed deformation model. See :cite:`LingleClark`, :cite:`BLKfastearth` 557 558 #. :config:`bed_deformation.mantle_density` (*number*) 559 560 :Value: 3300 (kg meter-3) 561 :Description: half-space (mantle) density used by the bed deformation model. See :cite:`LingleClark`, :cite:`BLKfastearth` 562 563 #. :config:`bed_deformation.mantle_viscosity` (*number*) 564 565 :Value: 1.000000e+21 (Pascal second) 566 :Description: half-space (mantle) viscosity used by the bed deformation model. See :cite:`LingleClark`, :cite:`BLKfastearth` 567 568 #. :config:`bed_deformation.model` (*keyword*) 569 570 :Value: ``none`` 571 :Choices: ``none, iso, lc`` 572 :Option: :opt:`-bed_def` 573 :Description: Selects a bed deformation model to use. 'iso' is point-wise isostasy, 'lc' is the Lingle-Clark model (see :cite:`LingleClark`, requires FFTW3). 574 575 #. :config:`bootstrapping.defaults.bed` (*number*) 576 577 :Value: 1 (meters) 578 :Description: bed elevation value to use if topg (bedrock_altitude) variable is absent in bootstrapping file 579 580 #. :config:`bootstrapping.defaults.bmelt` (*number*) 581 582 :Value: 0 (meter / second) 583 :Description: basal melt rate value to use if variable bmelt is absent in bootstrapping file 584 585 #. :config:`bootstrapping.defaults.bwat` (*number*) 586 587 :Value: 0 (meters) 588 :Description: till water thickness value to use if variable tillwat is absent in bootstrapping file 589 590 #. :config:`bootstrapping.defaults.bwp` (*number*) 591 592 :Value: 0 (Pascal) 593 :Description: basal water pressure value to use if variable bwp is absent in bootstrapping file; most hydrology models do not use this value because bwp is diagnostic 594 595 #. :config:`bootstrapping.defaults.enwat` (*number*) 596 597 :Value: 0 (meters) 598 :Description: effective englacial water thickness value to use if variable enwat is absent in bootstrapping file 599 600 #. :config:`bootstrapping.defaults.geothermal_flux` (*number*) 601 602 :Value: 0.042000 (Watt meter-2) 603 :Description: geothermal flux value to use if bheatflx variable is absent in bootstrapping file 604 605 #. :config:`bootstrapping.defaults.ice_thickness` (*number*) 606 607 :Value: 0 (meters) 608 :Description: thickness value to use if thk (land_ice_thickness) variable is absent in bootstrapping file 609 610 #. :config:`bootstrapping.defaults.tillwat` (*number*) 611 612 :Value: 0 (meters) 613 :Description: till water thickness value to use if variable tillwat is absent in bootstrapping file 614 615 #. :config:`bootstrapping.defaults.uplift` (*number*) 616 617 :Value: 0 (meter / second) 618 :Description: uplift value to use if dbdt variable is absent in bootstrapping file 619 620 #. :config:`bootstrapping.temperature_heuristic` (*keyword*) 621 622 :Value: ``smb`` 623 :Choices: ``smb, quartic_guess`` 624 :Option: :opt:`-boot_temperature_heuristic` 625 :Description: The heuristic to use to initialize ice temperature during bootstrapping: 'smb' uses the surface mass balance, surface temperature, and the geothermal flux, 'quartic_guess' uses the surface temperature and the geothermal flux. 626 627 #. :config:`calving.eigen_calving.K` (*number*) 628 629 :Value: 0 (meter second) 630 :Option: :opt:`-eigen_calving_K` 631 :Description: Set proportionality constant to determine calving rate from strain rates. Note references :cite:`Levermannetal2012`, :cite:`Martinetal2011` use K in range `10^{9}` to `3 \times 10^{11}` m a, that is, `3 \times 10^{16}` to `10^{19}` m s. 632 633 #. :config:`calving.float_kill.calve_near_grounding_line` (*flag*) 634 635 :Value: yes 636 :Option: :opt:`-float_kill_calve_near_grounding_line` 637 :Description: Calve floating ice near the grounding line. 638 639 #. :config:`calving.float_kill.margin_only` (*flag*) 640 641 :Value: no 642 :Option: :opt:`-float_kill_margin_only` 643 :Description: Apply float_kill at ice margin cells only. 644 645 #. :config:`calving.hayhurst_calving.B_tilde` (*number*) 646 647 :Value: 65 ((MPa)^r / year) 648 :Description: Effective damage rate :cite:`Mercenier2018` 649 650 #. :config:`calving.hayhurst_calving.exponent_r` (*number*) 651 652 :Value: 0.430000 (1) 653 :Description: Damage law exponent :cite:`Mercenier2018` 654 655 #. :config:`calving.hayhurst_calving.sigma_threshold` (*number*) 656 657 :Value: 0.170000 (MPa) 658 :Description: Damage threshold stress :cite:`Mercenier2018` 659 660 #. :config:`calving.methods` (*string*) 661 662 :Value: *no default* 663 :Option: :opt:`-calving` 664 :Description: comma-separated list of calving methods; one or more of 'eigen_calving', 'float_kill', 'thickness_calving' 665 666 #. :config:`calving.thickness_calving.threshold` (*number*) 667 668 :Value: 50 (meters) 669 :Option: :opt:`-thickness_calving_threshold` 670 :Description: When terminal ice thickness of floating ice shelf is less than this threshold, it will be calved off. 671 672 #. :config:`calving.thickness_calving.threshold_file` (*string*) 673 674 :Value: *no default* 675 :Option: :opt:`-thickness_calving_threshold_file` 676 :Description: Name of the file containing the spatially-variable thickness calving threshold. 677 678 #. :config:`calving.vonmises_calving.Glen_exponent` (*number*) 679 680 :Value: 3 (pure number) 681 :Option: :opt:`-vonmises_calving_n` 682 :Description: Glen exponent in ice flow law for von Mises calving 683 684 #. :config:`calving.vonmises_calving.enhancement_factor` (*number*) 685 686 :Value: 1 (1) 687 :Description: Flow enhancement factor used by the flow law in the von Mises stress computation 688 689 #. :config:`calving.vonmises_calving.enhancement_factor_interglacial` (*number*) 690 691 :Value: 1 (1) 692 :Description: Flow enhancement factor used by the flow law in the von Mises stress computation (for ice accumulated during interglacial periods). 693 694 #. :config:`calving.vonmises_calving.flow_law` (*keyword*) 695 696 :Value: ``gpbld`` 697 :Choices: ``arr, arrwarm, gpbld, hooke, isothermal_glen, pb`` 698 :Description: The custom flow law for the von Mises stress computation 699 700 #. :config:`calving.vonmises_calving.sigma_max` (*number*) 701 702 :Value: 1000000 (Pa) 703 :Option: :opt:`-vonmises_calving_calving_sigma_max` 704 :Description: Set maximum tensile stress. Note references :cite:`Morlighem2016` use 1.0e6 Pa. 705 706 #. :config:`calving.vonmises_calving.threshold_file` (*string*) 707 708 :Value: *no default* 709 :Option: :opt:`-vonmises_calving_threshold_file` 710 :Description: Name of the file containing the spatially-variable vonmises_calving calving threshold. 711 712 #. :config:`calving.vonmises_calving.use_custom_flow_law` (*flag*) 713 714 :Value: no 715 :Option: :opt:`-vonmises_calving_use_custom_flow_law` 716 :Description: Use custom flow law in the von Mises stress computation 717 718 #. :config:`constants.fresh_water.density` (*number*) 719 720 :Value: 1000 (kg meter-3) 721 :Description: density of fresh water 722 723 #. :config:`constants.fresh_water.latent_heat_of_fusion` (*number*) 724 725 :Value: 334000 (Joule / kg) 726 :Description: latent heat of fusion for water :cite:`AschwandenBlatter` 727 728 #. :config:`constants.fresh_water.melting_point_temperature` (*number*) 729 730 :Value: 273.150000 (Kelvin) 731 :Description: melting point of pure water 732 733 #. :config:`constants.fresh_water.specific_heat_capacity` (*number*) 734 735 :Value: 4170 (Joule / (kg Kelvin)) 736 :Description: at melting point T_0 :cite:`AschwandenBlatter` 737 738 #. :config:`constants.global_ocean_area` (*number*) 739 740 :Value: 3.625000e+14 (meter2) 741 :Description: area of the global ocean :cite:`Cogley2011` 742 743 #. :config:`constants.ice.beta_Clausius_Clapeyron` (*number*) 744 745 :Value: 7.900000e-08 (Kelvin / Pascal) 746 :Description: Clausius-Clapeyron constant relating melting temperature and pressure: `\beta = dT / dP` :cite:`Luethi2002` 747 748 #. :config:`constants.ice.density` (*number*) 749 750 :Value: 910 (kg meter-3) 751 :Description: `\rho_i`; density of ice in ice sheet 752 753 #. :config:`constants.ice.grain_size` (*number*) 754 755 :Value: 1 (mm) 756 :Option: :opt:`-ice_grain_size` 757 :Description: Default constant ice grain size to use with the Goldsby-Kohlstedt :cite:`GoldsbyKohlstedt` flow law 758 759 #. :config:`constants.ice.specific_heat_capacity` (*number*) 760 761 :Value: 2009 (Joule / (kg Kelvin)) 762 :Description: specific heat capacity of pure ice at melting point T_0 763 764 #. :config:`constants.ice.thermal_conductivity` (*number*) 765 766 :Value: 2.100000 (Joule / (meter Kelvin second)) 767 :Description: = W m-1 K-1; thermal conductivity of pure ice 768 769 #. :config:`constants.ideal_gas_constant` (*number*) 770 771 :Value: 8.314410 (Joule / (mol Kelvin)) 772 :Description: ideal gas constant 773 774 #. :config:`constants.sea_water.density` (*number*) 775 776 :Value: 1028 (kg meter-3) 777 :Description: density of sea water 778 779 #. :config:`constants.sea_water.specific_heat_capacity` (*number*) 780 781 :Value: 3985 (Joule / (kg Kelvin)) 782 :Description: at 35 psu, value taken from `Kaye and Laby`_, section 2.7.9 783 784 #. :config:`constants.standard_gravity` (*number*) 785 786 :Value: 9.810000 (meter second-2) 787 :Description: acceleration due to gravity on Earth geoid 788 789 #. :config:`energy.allow_temperature_above_melting` (*flag*) 790 791 :Value: no 792 :Description: If set to 'yes', allow temperatures above the pressure-malting point in the cold mode temperature code. Used by some verifiaction tests. 793 794 #. :config:`energy.basal_melt.use_grounded_cell_fraction` (*flag*) 795 796 :Value: true 797 :Option: :opt:`-subgl_basal_melt` 798 :Description: If geometry.grounded_cell_fraction is set, use the fractional floatation mask to interpolate the basal melt rate at the grounding line between grounded and floating values. 799 800 #. :config:`energy.bedrock_thermal.conductivity` (*number*) 801 802 :Value: 3 (Joule / (meter Kelvin second)) 803 :Description: = W m-1 K-1; for bedrock used in thermal model :cite:`RitzEISMINT` 804 805 #. :config:`energy.bedrock_thermal.density` (*number*) 806 807 :Value: 3300 (kg meter-3) 808 :Description: for bedrock used in thermal model 809 810 #. :config:`energy.bedrock_thermal.file` (*string*) 811 812 :Value: *no default* 813 :Description: Name of the file containing the geothermal flux field :var:`bheatflx`. Leave empty to read it from the :config:`input.file`. 814 815 #. :config:`energy.bedrock_thermal.specific_heat_capacity` (*number*) 816 817 :Value: 1000 (Joule / (kg Kelvin)) 818 :Description: for bedrock used in thermal model :cite:`RitzEISMINT` 819 820 #. :config:`energy.ch_warming.average_channel_spacing` (*number*) 821 822 :Value: 20 (meters) 823 :Description: Average spacing between elements of the cryo-hydrologic system (controls the rate of heat transfer from the CH system into the ice). 824 825 #. :config:`energy.ch_warming.enabled` (*flag*) 826 827 :Value: no 828 :Description: Enable the cryo-hydrologic warming model 829 830 #. :config:`energy.ch_warming.residual_water_fraction` (*number*) 831 832 :Value: 0.005000 (pure number) 833 :Description: residual water fraction in the cryo-hydrologic system at the end of a melt season 834 835 #. :config:`energy.ch_warming.temperate_ice_thermal_conductivity_ratio` (*number*) 836 837 :Value: 1 (pure number) 838 :Description: ratio of thermal conductivities of temperate and cold ice in the cryo-hydrologic system 839 840 #. :config:`energy.drainage_maximum_rate` (*number*) 841 842 :Value: 1.584438e-09 (second-1) 843 :Description: 0.05 year-1; maximum rate at which liquid water fraction in temperate ice could possibly drain; see :cite:`AschwandenBuelerKhroulevBlatter` 844 845 #. :config:`energy.drainage_target_water_fraction` (*number*) 846 847 :Value: 0.010000 (1) 848 :Description: liquid water fraction (omega) above which drainage occurs, but below which there is no drainage; see :cite:`AschwandenBuelerKhroulevBlatter` 849 850 #. :config:`energy.enabled` (*flag*) 851 852 :Value: yes 853 :Description: Solve energy conservation equations. 854 855 #. :config:`energy.enthalpy.cold_bulge_max` (*number*) 856 857 :Value: 60270 (Joule / kg) 858 :Description: = (2009 J kg-1 K-1) * (30 K); maximum amount by which advection can reduce the enthalpy of a column of ice below its surface enthalpy value 859 860 #. :config:`energy.enthalpy.temperate_ice_thermal_conductivity_ratio` (*number*) 861 862 :Value: 0.100000 (pure number) 863 :Description: K in cold ice is multiplied by this fraction to give K0 in :cite:`AschwandenBuelerKhroulevBlatter` 864 865 #. :config:`energy.margin_exclude_horizontal_advection` (*flag*) 866 867 :Value: yes 868 :Description: Exclude horizontal advection of energy at grid points near ice margins. See :config:`energy.margin_ice_thickness_limit`. 869 870 #. :config:`energy.margin_exclude_strain_heating` (*flag*) 871 872 :Value: yes 873 :Description: Exclude strain heating at grid points near ice margins. See :config:`energy.margin_ice_thickness_limit`. 874 875 #. :config:`energy.margin_exclude_vertical_advection` (*flag*) 876 877 :Value: yes 878 :Description: Exclude vertical advection of energy at grid points near ice margins. See :config:`energy.margin_ice_thickness_limit`. 879 880 #. :config:`energy.margin_ice_thickness_limit` (*number*) 881 882 :Value: 100 (meters) 883 :Description: use special margin treatment at grid points with a neighbor with the thickness below this limit. 884 885 #. :config:`energy.max_low_temperature_count` (*integer*) 886 887 :Value: 10 888 :Option: :opt:`-max_low_temps` 889 :Description: Maximum number of grid points with ice temperature below energy.minimum_allowed_temperature. 890 891 #. :config:`energy.minimum_allowed_temperature` (*number*) 892 893 :Value: 200 (Kelvin) 894 :Option: :opt:`-low_temp` 895 :Description: Minimum allowed ice temperature 896 897 #. :config:`energy.temperature_based` (*flag*) 898 899 :Value: no 900 :Description: Use cold ice (i.e. not polythermal) methods. 901 902 #. :config:`energy.temperature_dependent_thermal_conductivity` (*flag*) 903 904 :Value: no 905 :Option: :opt:`-vark` 906 :Description: If yes, use varkenthSystemCtx class in the energy step. It is base on formula (4.37) in :cite:`GreveBlatter2009`. Otherwise use enthSystemCtx, which has temperature-independent thermal conductivity set by constant ice.thermal_conductivity. 907 908 #. :config:`enthalpy_converter.T_reference` (*number*) 909 910 :Value: 223.150000 (Kelvin) 911 :Description: = T_0 in enthalpy formulas in :cite:`AschwandenBuelerKhroulevBlatter` 912 913 #. :config:`enthalpy_converter.relaxed_is_temperate_tolerance` (*number*) 914 915 :Value: 0.001000 (Kelvin) 916 :Description: Tolerance within which ice is treated as temperate (cold-ice mode and diagnostics). 917 918 #. :config:`flow_law.Hooke.A` (*number*) 919 920 :Value: 4.421650e-09 (Pascal-3 second-1) 921 :Description: `A_{\text{Hooke}} = (1/B_0)^n` where n=3 and B_0 = 1.928 `a^{1/3}` Pa. See :cite:`Hooke` 922 923 #. :config:`flow_law.Hooke.C` (*number*) 924 925 :Value: 0.166120 (Kelvin^{flow_law.Hooke.k}) 926 :Description: See :cite:`Hooke` 927 928 #. :config:`flow_law.Hooke.Q` (*number*) 929 930 :Value: 78800 (Joule / mol) 931 :Description: Activation energy, see :cite:`Hooke` 932 933 #. :config:`flow_law.Hooke.Tr` (*number*) 934 935 :Value: 273.390000 (Kelvin) 936 :Description: See :cite:`Hooke` 937 938 #. :config:`flow_law.Hooke.k` (*number*) 939 940 :Value: 1.170000 (pure number) 941 :Description: See :cite:`Hooke` 942 943 #. :config:`flow_law.Paterson_Budd.A_cold` (*number*) 944 945 :Value: 3.610000e-13 (Pascal-3 / second) 946 :Description: Paterson-Budd A_cold, see :cite:`PatersonBudd` 947 948 #. :config:`flow_law.Paterson_Budd.A_warm` (*number*) 949 950 :Value: 1730 (Pascal-3 / second) 951 :Description: Paterson-Budd A_warm, see :cite:`PatersonBudd` 952 953 #. :config:`flow_law.Paterson_Budd.Q_cold` (*number*) 954 955 :Value: 60000 (Joule / mol) 956 :Description: Paterson-Budd Q_cold, see :cite:`PatersonBudd` 957 958 #. :config:`flow_law.Paterson_Budd.Q_warm` (*number*) 959 960 :Value: 139000 (Joule / mol) 961 :Description: Paterson-Budd Q_warm, see :cite:`PatersonBudd` 962 963 #. :config:`flow_law.Paterson_Budd.T_critical` (*number*) 964 965 :Value: 263.150000 (Kelvin) 966 :Description: Paterson-Budd critical temperature, see :cite:`PatersonBudd` 967 968 #. :config:`flow_law.Schoof_regularizing_length` (*number*) 969 970 :Value: 1000 (km) 971 :Description: Regularizing length (Schoof definition) 972 973 #. :config:`flow_law.Schoof_regularizing_velocity` (*number*) 974 975 :Value: 1 (meter / year) 976 :Description: Regularizing velocity (Schoof definition) 977 978 #. :config:`flow_law.gpbld.water_frac_coeff` (*number*) 979 980 :Value: 181.250000 (pure number) 981 :Description: coefficient in Glen-Paterson-Budd flow law for extra dependence of softness on liquid water fraction (omega) :cite:`GreveBlatter2009`, :cite:`LliboutryDuval1985` 982 983 #. :config:`flow_law.gpbld.water_frac_observed_limit` (*number*) 984 985 :Value: 0.010000 (1) 986 :Description: maximum value of liquid water fraction omega for which softness values are parameterized by :cite:`LliboutryDuval1985`; used in Glen-Paterson-Budd-Lliboutry-Duval flow law; compare :cite:`AschwandenBuelerKhroulevBlatter` 987 988 #. :config:`flow_law.isothermal_Glen.ice_softness` (*number*) 989 990 :Value: 3.168900e-24 (Pascal-3 second-1) 991 :Description: ice softness used by IsothermalGlenIce :cite:`EISMINT96` 992 993 #. :config:`fracture_density.constant_fd` (*flag*) 994 995 :Value: no 996 :Option: :opt:`-constant_fd` 997 :Description: FIXME 998 999 #. :config:`fracture_density.constant_healing` (*flag*) 1000 1001 :Value: no 1002 :Option: :opt:`-constant_healing` 1003 :Description: Constant healing 1004 1005 #. :config:`fracture_density.enabled` (*flag*) 1006 1007 :Value: no 1008 :Option: :opt:`-fractures` 1009 :Description: Calculation of fracture density according to stresses and strain rate field. 1010 1011 #. :config:`fracture_density.fd2d_scheme` (*flag*) 1012 1013 :Value: no 1014 :Option: :opt:`-scheme_fd2d` 1015 :Description: FIXME 1016 1017 #. :config:`fracture_density.fracture_weighted_healing` (*flag*) 1018 1019 :Value: no 1020 :Option: :opt:`-fracture_weighted_healing` 1021 :Description: Fracture weighted healing 1022 1023 #. :config:`fracture_density.include_grounded_ice` (*flag*) 1024 1025 :Value: no 1026 :Option: :opt:`-do_frac_on_grounded` 1027 :Description: model fracture density in grounded areas 1028 1029 #. :config:`fracture_density.lefm` (*flag*) 1030 1031 :Value: no 1032 :Option: :opt:`-lefm` 1033 :Description: FIXME 1034 1035 #. :config:`fracture_density.max_shear_stress` (*flag*) 1036 1037 :Value: no 1038 :Option: :opt:`-max_shear` 1039 :Description: Use the max. shear stress criterion. 1040 1041 #. :config:`fracture_density.phi0` (*number*) 1042 1043 :Value: 0 (1) 1044 :Option: :opt:`-phi0` 1045 :Description: FIXME 1046 1047 #. :config:`fracture_density.softening_lower_limit` (*number*) 1048 1049 :Value: 1 (1) 1050 :Option: :opt:`-fracture_softening` 1051 :Description: epsilon in equation (6) in Albrecht and Levermann, 'Fracture-induced softening for large-scale ice dynamics' 1052 1053 #. :config:`frontal_melt.constant.melt_rate` (*number*) 1054 1055 :Value: 1 (m / day) 1056 :Option: :opt:`-frontal_melt_rate` 1057 :Description: default melt rate used by the 'constant' frontal_melt model 1058 1059 #. :config:`frontal_melt.discharge_given.file` (*string*) 1060 1061 :Value: *no default* 1062 :Option: :opt:`-frontal_melt_discharge_given_file` 1063 :Description: Name of the file containing climate forcing fields. 1064 1065 #. :config:`frontal_melt.discharge_given.period` (*integer*) 1066 1067 :Value: 0 1068 :Option: :opt:`-frontal_melt_discharge_given_period` 1069 :Description: Length of the period of the climate forcing data. Set to zero to disable. 1070 1071 #. :config:`frontal_melt.discharge_given.reference_year` (*integer*) 1072 1073 :Value: 0 1074 :Option: :opt:`-frontal_melt_discharge_given_reference_year` 1075 :Description: Reference year to use when ``frontal_melt.discharge_given.period`` is active. 1076 1077 #. :config:`frontal_melt.given.file` (*string*) 1078 1079 :Value: *no default* 1080 :Option: :opt:`-frontal_melt_given_file` 1081 :Description: Name of the file containing climate forcing fields. 1082 1083 #. :config:`frontal_melt.given.period` (*integer*) 1084 1085 :Value: 0 1086 :Option: :opt:`-frontal_melt_given_period` 1087 :Description: Length of the period of the climate forcing data. Set to zero to disable. 1088 1089 #. :config:`frontal_melt.given.reference_year` (*integer*) 1090 1091 :Value: 0 1092 :Option: :opt:`-frontal_melt_given_reference_year` 1093 :Description: Reference year to use when ``frontal_melt.given.period`` is active. 1094 1095 #. :config:`frontal_melt.include_floating_ice` (*flag*) 1096 1097 :Value: no 1098 :Description: Apply frontal melt to all grid icy cells next to ocean cells 1099 1100 #. :config:`frontal_melt.models` (*string*) 1101 1102 :Value: *no default* 1103 :Option: :opt:`-frontal_melt` 1104 :Description: Comma-separated list of frontal melt models and modifiers. (Leave empty to disable.) 1105 1106 #. :config:`frontal_melt.routing.file` (*string*) 1107 1108 :Value: *no default* 1109 :Option: :opt:`-frontal_melt_routing_file` 1110 :Description: Name of the file containing climate forcing fields. 1111 1112 #. :config:`frontal_melt.routing.parameter_a` (*number*) 1113 1114 :Value: 0.000300 (m-alpha day^(alpha-1) Celsius-beta) 1115 :Description: parameter A in eqn. 1 in :cite:`Xu2013` 1116 1117 #. :config:`frontal_melt.routing.parameter_b` (*number*) 1118 1119 :Value: 0.150000 (m day^(alpha-1) Celsius-beta) 1120 :Description: parameter B in eqn. 1 in :cite:`Xu2013` 1121 1122 #. :config:`frontal_melt.routing.period` (*integer*) 1123 1124 :Value: 0 1125 :Option: :opt:`-frontal_melt_routing_period` 1126 :Description: Length of the period of the climate forcing data. Set to zero to disable. 1127 1128 #. :config:`frontal_melt.routing.power_alpha` (*number*) 1129 1130 :Value: 0.390000 (1) 1131 :Description: exponent `\alpha` in eqn. 1 in :cite:`Xu2013` 1132 1133 #. :config:`frontal_melt.routing.power_beta` (*number*) 1134 1135 :Value: 1.180000 (1) 1136 :Description: exponent `\beta` in eqn. 1 in :cite:`Xu2013` 1137 1138 #. :config:`frontal_melt.routing.reference_year` (*integer*) 1139 1140 :Value: 0 1141 :Option: :opt:`-frontal_melt_routing_reference_year` 1142 :Description: Reference year to use when ``frontal_melt.routing.period`` is active. 1143 1144 #. :config:`geometry.front_retreat.prescribed.file` (*string*) 1145 1146 :Value: *no default* 1147 :Option: :opt:`-front_retreat_file` 1148 :Description: Name of the file containing the maximum ice extent mask `land_ice_area_fraction_retreat` 1149 1150 #. :config:`geometry.front_retreat.prescribed.period` (*integer*) 1151 1152 :Value: 0 1153 :Description: Length of the period of the front retreat data. Set to zero to disable. 1154 1155 #. :config:`geometry.front_retreat.prescribed.reference_year` (*integer*) 1156 1157 :Value: 0 1158 :Description: Reference year to use when `geometry.front_retreat.prescribed.period` is active. 1159 1160 #. :config:`geometry.front_retreat.use_cfl` (*flag*) 1161 1162 :Value: false 1163 :Option: :opt:`-front_retreat_cfl` 1164 :Description: apply CFL criterion for eigen-calving rate front retreat 1165 1166 #. :config:`geometry.front_retreat.wrap_around` (*flag*) 1167 1168 :Value: false 1169 :Option: :opt:`-front_retreat_wrap_around` 1170 :Description: If true, wrap around domain boundaries. This may be needed in some regional synthetic geometry setups. 1171 1172 #. :config:`geometry.grounded_cell_fraction` (*flag*) 1173 1174 :Value: false 1175 :Option: :opt:`-subgl` 1176 :Description: Linear interpolation scheme ('LI' in Gladstone et al. 2010) expanded to two dimensions is used if switched on in order to evaluate the position of the grounding line on a subgrid scale. 1177 1178 #. :config:`geometry.ice_free_thickness_standard` (*number*) 1179 1180 :Value: 0.010000 (meters) 1181 :Description: If ice is thinner than this standard then the mask is set to MASK_ICE_FREE_BEDROCK or MASK_ICE_FREE_OCEAN. 1182 1183 #. :config:`geometry.part_grid.enabled` (*flag*) 1184 1185 :Value: no 1186 :Option: :opt:`-part_grid` 1187 :Description: apply partially filled grid cell scheme 1188 1189 #. :config:`geometry.part_grid.max_iterations` (*integer*) 1190 1191 :Value: 10 1192 :Description: maximum number of residual redistribution iterations 1193 1194 #. :config:`geometry.remove_icebergs` (*flag*) 1195 1196 :Value: no 1197 :Option: :opt:`-kill_icebergs` 1198 :Description: identify and kill detached ice-shelf areas 1199 1200 #. :config:`geometry.update.enabled` (*flag*) 1201 1202 :Value: yes 1203 :Option: :opt:`-mass` 1204 :Description: Solve the mass conservation equation 1205 1206 #. :config:`geometry.update.use_basal_melt_rate` (*flag*) 1207 1208 :Value: yes 1209 :Option: :opt:`-bmr_in_cont` 1210 :Description: Include basal melt rate in the continuity equation 1211 1212 #. :config:`grid.Lbz` (*number*) 1213 1214 :Value: 1000 (meters) 1215 :Option: :opt:`-Lbz` 1216 :Description: Thickness of the thermal bedrock layer. (Inactive if ``grid.Mbz`` < 2) 1217 1218 #. :config:`grid.Lx` (*number*) 1219 1220 :Value: 1500000 (meters) 1221 :Description: Default computational box is 3000 km x 3000 km (= 2 Lx x 2 Ly) in horizontal. 1222 1223 #. :config:`grid.Ly` (*number*) 1224 1225 :Value: 1500000 (meters) 1226 :Description: Default computational box is 3000 km x 3000 km (= 2 Lx x 2 Ly) in horizontal. 1227 1228 #. :config:`grid.Lz` (*number*) 1229 1230 :Value: 4000 (meters) 1231 :Option: :opt:`-Lz` 1232 :Description: Height of the computational domain. 1233 1234 #. :config:`grid.Mbz` (*integer*) 1235 1236 :Value: 1 1237 :Option: :opt:`-Mbz` 1238 :Description: Number of thermal bedrock layers; 1 level corresponds to no bedrock. 1239 1240 #. :config:`grid.Mx` (*integer*) 1241 1242 :Value: 61 1243 :Option: :opt:`-Mx` 1244 :Description: Number of grid points in the x direction. 1245 1246 #. :config:`grid.My` (*integer*) 1247 1248 :Value: 61 1249 :Option: :opt:`-My` 1250 :Description: Number of grid points in the y direction. 1251 1252 #. :config:`grid.Mz` (*integer*) 1253 1254 :Value: 31 1255 :Option: :opt:`-Mz` 1256 :Description: Number of vertical grid levels in the ice. 1257 1258 #. :config:`grid.allow_extrapolation` (*flag*) 1259 1260 :Value: no 1261 :Option: :opt:`-allow_extrapolation` 1262 :Description: Allow extrapolation during regridding. 1263 1264 #. :config:`grid.ice_vertical_spacing` (*keyword*) 1265 1266 :Value: ``quadratic`` 1267 :Choices: ``quadratic, equal`` 1268 :Option: :opt:`-z_spacing` 1269 :Description: vertical spacing in the ice 1270 1271 #. :config:`grid.lambda` (*number*) 1272 1273 :Value: 4 (pure number) 1274 :Description: Vertical grid spacing parameter. Roughly equal to the factor by which the grid is coarser at an end away from the ice-bedrock interface. 1275 1276 #. :config:`grid.max_stencil_width` (*integer*) 1277 1278 :Value: 2 1279 :Description: Maximum width of the finite-difference stencil used in PISM. 1280 1281 #. :config:`grid.periodicity` (*keyword*) 1282 1283 :Value: ``xy`` 1284 :Choices: ``none, x, y, xy`` 1285 :Option: :opt:`-periodicity` 1286 :Description: horizontal grid periodicity 1287 1288 #. :config:`grid.recompute_longitude_and_latitude` (*flag*) 1289 1290 :Value: yes 1291 :Description: Re-compute longitude and latitude using grid information and provided projection parameters. Requires PROJ. 1292 1293 #. :config:`grid.registration` (*keyword*) 1294 1295 :Value: ``center`` 1296 :Choices: ``center, corner`` 1297 :Description: horizontal grid registration 1298 1299 #. :config:`hydrology.add_water_input_to_till_storage` (*flag*) 1300 1301 :Value: yes 1302 :Description: Add surface input to water stored in till. If no it will be added to the transportable water. 1303 1304 #. :config:`hydrology.cavitation_opening_coefficient` (*number*) 1305 1306 :Value: 0.500000 (meter-1) 1307 :Option: :opt:`-hydrology_cavitation_opening_coefficient` 1308 :Description: c_1 in notes; coefficient of cavitation opening term in evolution of layer thickness in hydrology::Distributed 1309 1310 #. :config:`hydrology.creep_closure_coefficient` (*number*) 1311 1312 :Value: 0.040000 (pure number) 1313 :Option: :opt:`-hydrology_creep_closure_coefficient` 1314 :Description: c_2 in notes; coefficient of creep closure term in evolution of layer thickness in hydrology::Distributed 1315 1316 #. :config:`hydrology.distributed.init_p_from_steady` (*flag*) 1317 1318 :Value: no 1319 :Option: :opt:`-hydrology_init_p_form_steady` 1320 :Description: if 'yes', initialize subglacial water pressure from P(W) formula that applies in steady state 1321 1322 #. :config:`hydrology.distributed.sliding_speed_file` (*string*) 1323 1324 :Value: *no default* 1325 :Option: :opt:`-hydrology_sliding_speed_file` 1326 :Description: name of the file containing velbase_mag, the basal sliding speed to use with :literal:`hydrology.distributed.init_p_from_steady` 1327 1328 #. :config:`hydrology.gradient_power_in_flux` (*number*) 1329 1330 :Value: 1.500000 (pure number) 1331 :Option: :opt:`-hydrology_gradient_power_in_flux` 1332 :Description: power `\beta` in Darcy's law `q = - k W^{\alpha} |\nabla \psi|^{\beta-2} \nabla \psi`, for subglacial water layer; used by hydrology::Routing and hydrology::Distributed 1333 1334 #. :config:`hydrology.hydraulic_conductivity` (*number*) 1335 1336 :Value: 0.001000 (`m^{2 \beta - \alpha} s^{2 \beta - 3} kg^{1-\beta}`) 1337 :Option: :opt:`-hydrology_hydraulic_conductivity` 1338 :Description: = k in notes; lateral conductivity, in Darcy's law, for subglacial water layer; units depend on powers alpha = hydrology.thickness_power_in_flux and beta = hydrology_potential_gradient_power_in_flux; used by hydrology::Routing and hydrology::Distributed 1339 1340 #. :config:`hydrology.maximum_time_step` (*number*) 1341 1342 :Value: 1 (years) 1343 :Description: maximum allowed time step length used by hydrology::Routing and hydrology::Distributed 1344 1345 #. :config:`hydrology.model` (*keyword*) 1346 1347 :Value: ``null`` 1348 :Choices: ``null, routing, steady, distributed`` 1349 :Option: :opt:`-hydrology` 1350 :Description: Basal hydrology sub-model. 1351 1352 #. :config:`hydrology.null_diffuse_till_water` (*flag*) 1353 1354 :Value: no 1355 :Description: Diffuse stored till water laterally. See equation (11) of :cite:`BBssasliding` 1356 1357 #. :config:`hydrology.null_diffusion_distance` (*number*) 1358 1359 :Value: 20000 (meters) 1360 :Description: diffusion distance for till water thickness; see equation (11) in :cite:`BBssasliding`; only active if hydrology.null_diffuse_till_water is set 1361 1362 #. :config:`hydrology.null_diffusion_time` (*number*) 1363 1364 :Value: 1000 (years) 1365 :Description: diffusion time for till water thickness; see equation (11) in :cite:`BBssasliding`; only active if hydrology.null_diffuse_till_water is set 1366 1367 #. :config:`hydrology.null_strip_width` (*number*) 1368 1369 :Value: -1 (meters) 1370 :Description: if negative then mechanism is inactive; width of strip around computational domain in which water velocity and water amount are set to zero; used by hydrology::Routing and hydrology::Distributed 1371 1372 #. :config:`hydrology.regularizing_porosity` (*number*) 1373 1374 :Value: 0.010000 (pure number) 1375 :Option: :opt:`-hydrology_regularizing_porosity` 1376 :Description: phi_0 in notes; regularizes pressure equation by multiplying time derivative term 1377 1378 #. :config:`hydrology.roughness_scale` (*number*) 1379 1380 :Value: 0.100000 (meters) 1381 :Option: :opt:`-hydrology_roughness_scale` 1382 :Description: W_r in notes; roughness scale determining maximum amount of cavitation opening in hydrology::Distributed 1383 1384 #. :config:`hydrology.routing.include_floating_ice` (*flag*) 1385 1386 :Value: no 1387 :Description: Route subglacial water under ice shelves. This may be appropriate if a shelf is close to floatation. Note that this has no effect on ice flow. 1388 1389 #. :config:`hydrology.steady.flux_update_interval` (*number*) 1390 1391 :Value: 1 (years) 1392 :Description: interval between updates of the steady state flux 1393 1394 #. :config:`hydrology.steady.input_rate_scaling` (*number*) 1395 1396 :Value: 1.000000e+07 (seconds) 1397 :Description: input rate scaling 1398 1399 #. :config:`hydrology.steady.n_iterations` (*integer*) 1400 1401 :Value: 7500 1402 :Description: maxinum number of iterations to use in while estimating steady-state water flux 1403 1404 #. :config:`hydrology.steady.potential_delta` (*number*) 1405 1406 :Value: 10000 (Pa) 1407 :Description: potential adjustment used to fill sinks (smaller values require more iterations but produce fewer artifacts) 1408 1409 #. :config:`hydrology.steady.potential_n_iterations` (*integer*) 1410 1411 :Value: 1000 1412 :Description: maxinum number of iterations to take while pre-processing hydraulic potential 1413 1414 #. :config:`hydrology.steady.volume_ratio` (*number*) 1415 1416 :Value: 0.100000 (1) 1417 :Description: water volume ratio used as the stopping criterion 1418 1419 #. :config:`hydrology.surface_input.file` (*string*) 1420 1421 :Value: *no default* 1422 :Description: Name of the file containing ``water_input_rate``, the rate at which water from the ice surface is added to the subglacial hydrology system 1423 1424 #. :config:`hydrology.surface_input.period` (*integer*) 1425 1426 :Value: 0 1427 :Description: Length of the period of the water input rate. Set to zero to disable. 1428 1429 #. :config:`hydrology.surface_input.reference_year` (*integer*) 1430 1431 :Value: 0 1432 :Description: Reference year to use when ``hydrology.surface_input.period`` is active. 1433 1434 #. :config:`hydrology.surface_input_from_runoff` (*flag*) 1435 1436 :Value: no 1437 :Description: Use surface runoff as surface input. 1438 1439 #. :config:`hydrology.thickness_power_in_flux` (*number*) 1440 1441 :Value: 1.250000 (1) 1442 :Option: :opt:`-hydrology_thickness_power_in_flux` 1443 :Description: power `\alpha` in Darcy's law `q = - k W^{\alpha} |\nabla \psi|^{\beta-2} \nabla \psi`, for subglacial water layer; used by hydrology::Routing and hydrology::Distributed 1444 1445 #. :config:`hydrology.tillwat_decay_rate` (*number*) 1446 1447 :Value: 1 (mm / year) 1448 :Option: :opt:`-hydrology_tillwat_decay_rate` 1449 :Description: rate at which tillwat is reduced to zero, in absence of other effects like input 1450 1451 #. :config:`hydrology.tillwat_max` (*number*) 1452 1453 :Value: 2 (meters) 1454 :Option: :opt:`-hydrology_tillwat_max` 1455 :Description: maximum effective thickness of the water stored in till 1456 1457 #. :config:`hydrology.use_const_bmelt` (*flag*) 1458 1459 :Value: no 1460 :Option: :opt:`-hydrology_use_const_bmelt` 1461 :Description: if 'yes', subglacial hydrology model sees basal melt rate which is constant and given by hydrology.const_bmelt 1462 1463 #. :config:`input.bootstrap` (*flag*) 1464 1465 :Value: no 1466 :Option: :opt:`-bootstrap` 1467 :Description: It true, use bootstrapping heuristics when initializing PISM. 1468 1469 #. :config:`input.file` (*string*) 1470 1471 :Value: *no default* 1472 :Option: :opt:`-i` 1473 :Description: Input file name 1474 1475 #. :config:`input.forcing.buffer_size` (*integer*) 1476 1477 :Value: 60 1478 :Description: number of 2D climate forcing records to keep in memory; = 5 years of monthly records 1479 1480 #. :config:`input.forcing.evaluations_per_year` (*integer*) 1481 1482 :Value: 52 1483 :Description: length of the time-series used to compute temporal averages of forcing data (such as mean annual temperature) 1484 1485 #. :config:`input.regrid.file` (*string*) 1486 1487 :Value: *no default* 1488 :Option: :opt:`-regrid_file` 1489 :Description: Regridding (input) file name 1490 1491 #. :config:`input.regrid.vars` (*string*) 1492 1493 :Value: *no default* 1494 :Option: :opt:`-regrid_vars` 1495 :Description: Comma-separated list of variables to regrid. Leave empty to regrid all model state variables. 1496 1497 #. :config:`inverse.design.cH1` (*number*) 1498 1499 :Value: 0 (1) 1500 :Option: :opt:`-inv_design_cH1` 1501 :Description: weight of derivative part of an H1 norm for inversion design variables 1502 1503 #. :config:`inverse.design.cL2` (*number*) 1504 1505 :Value: 1 (1) 1506 :Option: :opt:`-inv_design_cL2` 1507 :Description: weight of derivative-free part of an H1 norm for inversion design variables 1508 1509 #. :config:`inverse.design.func` (*keyword*) 1510 1511 :Value: ``sobolevH1`` 1512 :Choices: ``sobolevH1, tv`` 1513 :Option: :opt:`-inv_design_func` 1514 :Description: functional used for inversion design variables 1515 1516 #. :config:`inverse.design.param` (*keyword*) 1517 1518 :Value: ``exp`` 1519 :Choices: ``ident, trunc, square, exp`` 1520 :Option: :opt:`-inv_design_param` 1521 :Description: parameterization of design variables used during inversion 1522 1523 #. :config:`inverse.design.param_hardav_eps` (*number*) 1524 1525 :Value: 10000 (Pascal second^(1/3)) 1526 :Description: tiny vertically-averaged hardness used as a substitute for 0 in some tauc parameterizations 1527 1528 #. :config:`inverse.design.param_hardav_scale` (*number*) 1529 1530 :Value: 1.000000e+08 (Pascal second^(1/3)) 1531 :Description: typical size of ice hardness 1532 1533 #. :config:`inverse.design.param_tauc_eps` (*number*) 1534 1535 :Value: 100 (Pascal) 1536 :Description: tiny yield stress used as a substitute for 0 in some tauc parameterizations 1537 1538 #. :config:`inverse.design.param_tauc_scale` (*number*) 1539 1540 :Value: 100000 (Pascal) 1541 :Description: typical size of yield stresses 1542 1543 #. :config:`inverse.design.param_trunc_hardav0` (*number*) 1544 1545 :Value: 1000000 (Pascal second^(1/3)) 1546 :Description: transition point of change to linear behaviour for design variable parameterization type 'trunc' 1547 1548 #. :config:`inverse.design.param_trunc_tauc0` (*number*) 1549 1550 :Value: 1000 (Pascal) 1551 :Description: transition point of change to linear behaviour for design variable parameterization type 'trunc' 1552 1553 #. :config:`inverse.log_ratio_scale` (*number*) 1554 1555 :Value: 10 (pure number) 1556 :Option: :opt:`-inv_log_ratio_scale` 1557 :Description: Reference scale for log-ratio functionals 1558 1559 #. :config:`inverse.max_iterations` (*integer*) 1560 1561 :Value: 1000 1562 :Option: :opt:`-inv_max_it` 1563 :Description: maximum iteration count 1564 1565 #. :config:`inverse.ssa.hardav_max` (*number*) 1566 1567 :Value: 1.000000e+10 (Pascal second^(1/3)) 1568 :Description: Maximum allowed value of hardav for inversions with bound constraints 1569 1570 #. :config:`inverse.ssa.hardav_min` (*number*) 1571 1572 :Value: 0 (Pascal second^(1/3)) 1573 :Description: Minimum allowed value of hardav for inversions with bound constraints 1574 1575 #. :config:`inverse.ssa.length_scale` (*number*) 1576 1577 :Value: 50000 (meters) 1578 :Description: typical length scale for rescaling derivative norms 1579 1580 #. :config:`inverse.ssa.method` (*keyword*) 1581 1582 :Value: ``tikhonov_lmvm`` 1583 :Choices: ``sd, nlcg, ign, tikhonov_lmvm, tikhonov_cg, tikhonov_blmvm, tikhonov_lcl, tikhonov_gn`` 1584 :Option: :opt:`-inv_method` 1585 :Description: algorithm to use for SSA inversions 1586 1587 #. :config:`inverse.ssa.tauc_max` (*number*) 1588 1589 :Value: 5.000000e+07 (Pascal) 1590 :Description: Maximum allowed value of tauc for inversions with bound constraints 1591 1592 #. :config:`inverse.ssa.tauc_min` (*number*) 1593 1594 :Value: 0 (Pascal) 1595 :Description: Minimum allowed value of tauc for inversions with bound constraints 1596 1597 #. :config:`inverse.ssa.tv_exponent` (*number*) 1598 1599 :Value: 1.200000 (pure number) 1600 :Option: :opt:`-inv_ssa_tv_exponent` 1601 :Description: Lebesgue exponent for pseudo-TV norm 1602 1603 #. :config:`inverse.ssa.velocity_eps` (*number*) 1604 1605 :Value: 0.100000 (meter / year) 1606 :Description: tiny size of ice velocities during inversion 1607 1608 #. :config:`inverse.ssa.velocity_scale` (*number*) 1609 1610 :Value: 100 (meter / year) 1611 :Description: typical size of ice velocities expected during inversion 1612 1613 #. :config:`inverse.state_func` (*keyword*) 1614 1615 :Value: ``meansquare`` 1616 :Choices: ``meansquare, log_ratio, log_relative`` 1617 :Option: :opt:`-inv_state_func` 1618 :Description: functional used for inversion design variables 1619 1620 #. :config:`inverse.target_misfit` (*number*) 1621 1622 :Value: 100 (meter / year) 1623 :Option: :opt:`-inv_target_misfit` 1624 :Description: desired root misfit for SSA inversions 1625 1626 #. :config:`inverse.tikhonov.atol` (*number*) 1627 1628 :Value: 1.000000e-10 (meter / year) 1629 :Option: :opt:`-tikhonov_atol` 1630 :Description: absolute threshold for Tikhonov stopping criterion 1631 1632 #. :config:`inverse.tikhonov.penalty_weight` (*number*) 1633 1634 :Value: 1 (1) 1635 :Option: :opt:`-tikhonov_penalty` 1636 :Description: penalty parameter for Tikhonov inversion 1637 1638 #. :config:`inverse.tikhonov.ptol` (*number*) 1639 1640 :Value: 0.100000 (pure number) 1641 :Option: :opt:`-tikhonov_ptol` 1642 :Description: threshold for reaching desired misfit for adaptive Tikhonov algorithms 1643 1644 #. :config:`inverse.tikhonov.rtol` (*number*) 1645 1646 :Value: 0.050000 (1) 1647 :Option: :opt:`-tikhonov_rtol` 1648 :Description: relative threshold for Tikhonov stopping criterion 1649 1650 #. :config:`inverse.use_design_prior` (*flag*) 1651 1652 :Value: yes 1653 :Option: :opt:`-inv_use_design_prior` 1654 :Description: Use prior from inverse data file as initial guess. 1655 1656 #. :config:`inverse.use_zeta_fixed_mask` (*flag*) 1657 1658 :Value: yes 1659 :Option: :opt:`-inv_use_zeta_fixed_mask` 1660 :Description: Enforce locations where the parameterized design variable should be fixed. (Automatically determined if not provided) 1661 1662 #. :config:`ocean.always_grounded` (*flag*) 1663 1664 :Value: no 1665 :Option: :opt:`-dry` 1666 :Description: Dry (ocean-less) simulation; ice is considered grounded regardless of ice thickness, bed elevation, and sea level. 1667 1668 #. :config:`ocean.anomaly.file` (*string*) 1669 1670 :Value: *no default* 1671 :Option: :opt:`-ocean_anomaly_file` 1672 :Description: Name of the file containing shelf basal mass flux offset fields. 1673 1674 #. :config:`ocean.anomaly.period` (*integer*) 1675 1676 :Value: 0 1677 :Option: :opt:`-ocean_anomaly_period` 1678 :Description: Length of the period of the ocean forcing data. Set to zero to disable. 1679 1680 #. :config:`ocean.anomaly.reference_year` (*integer*) 1681 1682 :Value: 0 1683 :Option: :opt:`-ocean_anomaly_reference_year` 1684 :Description: Reference year to use when ``ocean.anomaly.period`` is active. 1685 1686 #. :config:`ocean.cache.update_interval` (*integer*) 1687 1688 :Value: 10 1689 :Option: :opt:`-ocean_cache_update_interval` 1690 :Description: update interval of the 'cache' ocean modifier 1691 1692 #. :config:`ocean.constant.melange_back_pressure_fraction` (*number*) 1693 1694 :Value: 0 (1) 1695 :Description: default melange back pressure fraction in the 'contant' ocean model 1696 1697 #. :config:`ocean.constant.melt_rate` (*number*) 1698 1699 :Value: 0.051914 (m / year) 1700 :Option: :opt:`-shelf_base_melt_rate` 1701 :Description: default melt rate used by the 'constant' ocean model (computed as `Q / (L \rho_i)`) 1702 1703 #. :config:`ocean.delta_T.file` (*string*) 1704 1705 :Value: *no default* 1706 :Option: :opt:`-ocean_delta_T_file` 1707 :Description: Name of the file containing temperature offsets. 1708 1709 #. :config:`ocean.delta_T.period` (*integer*) 1710 1711 :Value: 0 1712 :Option: :opt:`-ocean_delta_T_period` 1713 :Description: Length of the period of the climate forcing data. Set to zero to disable. 1714 1715 #. :config:`ocean.delta_T.reference_year` (*integer*) 1716 1717 :Value: 0 1718 :Option: :opt:`-ocean_delta_T_reference_year` 1719 :Description: Reference year to use when ``ocean.delta_T.period`` is active. 1720 1721 #. :config:`ocean.delta_mass_flux.file` (*string*) 1722 1723 :Value: *no default* 1724 :Option: :opt:`-ocean_delta_mass_flux_file` 1725 :Description: Name of the file containing sub-shelf mass flux offsets. 1726 1727 #. :config:`ocean.delta_mass_flux.period` (*integer*) 1728 1729 :Value: 0 1730 :Option: :opt:`-ocean_delta_mass_flux_period` 1731 :Description: Length of the period of the climate forcing data. Set to zero to disable. 1732 1733 #. :config:`ocean.delta_mass_flux.reference_year` (*integer*) 1734 1735 :Value: 0 1736 :Option: :opt:`-ocean_delta_mass_flux_reference_year` 1737 :Description: Reference year to use when ``ocean.delta_mass_flux.period`` is active. 1738 1739 #. :config:`ocean.delta_sl.file` (*string*) 1740 1741 :Value: *no default* 1742 :Option: :opt:`-ocean_delta_sl_file` 1743 :Description: Name of the file containing sea level offsets. 1744 1745 #. :config:`ocean.delta_sl.period` (*integer*) 1746 1747 :Value: 0 1748 :Option: :opt:`-ocean_delta_sl_period` 1749 :Description: Length of the period of the climate forcing data. Set to zero to disable. 1750 1751 #. :config:`ocean.delta_sl.reference_year` (*integer*) 1752 1753 :Value: 0 1754 :Option: :opt:`-ocean_delta_sl_reference_year` 1755 :Description: Reference year to use when ``ocean.delta_sl.period`` is active. 1756 1757 #. :config:`ocean.delta_sl_2d.file` (*string*) 1758 1759 :Value: *no default* 1760 :Description: Name of the file containing climate forcing fields. 1761 1762 #. :config:`ocean.delta_sl_2d.period` (*integer*) 1763 1764 :Value: 0 1765 :Description: Length of the period of the climate forcing data. Set to zero to disable. 1766 1767 #. :config:`ocean.delta_sl_2d.reference_year` (*integer*) 1768 1769 :Value: 0 1770 :Description: Reference year to use when ``ocean.delta_sl_2d.period`` is active. 1771 1772 #. :config:`ocean.frac_MBP.file` (*string*) 1773 1774 :Value: *no default* 1775 :Option: :opt:`-ocean_frac_MBP_file` 1776 :Description: Name of the file containing melange back-pressure scaling. 1777 1778 #. :config:`ocean.frac_MBP.period` (*integer*) 1779 1780 :Value: 0 1781 :Option: :opt:`-ocean_frac_MBP_period` 1782 :Description: Length of the period of the climate forcing data. Set to zero to disable. 1783 1784 #. :config:`ocean.frac_MBP.reference_year` (*integer*) 1785 1786 :Value: 0 1787 :Option: :opt:`-ocean_frac_MBP_reference_year` 1788 :Description: Reference year to use when ``ocean.frac_MBP.period`` is active. 1789 1790 #. :config:`ocean.frac_mass_flux.file` (*string*) 1791 1792 :Value: *no default* 1793 :Option: :opt:`-ocean_frac_mass_flux_file` 1794 :Description: Name of the file containing sub-shelf mass flux scaling. 1795 1796 #. :config:`ocean.frac_mass_flux.period` (*integer*) 1797 1798 :Value: 0 1799 :Option: :opt:`-ocean_frac_mass_flux_period` 1800 :Description: Length of the period of the climate forcing data. Set to zero to disable. 1801 1802 #. :config:`ocean.frac_mass_flux.reference_year` (*integer*) 1803 1804 :Value: 0 1805 :Option: :opt:`-ocean_frac_mass_flux_reference_year` 1806 :Description: Reference year to use when ``ocean.frac_mass_flux.period`` is active. 1807 1808 #. :config:`ocean.given.file` (*string*) 1809 1810 :Value: *no default* 1811 :Option: :opt:`-ocean_given_file` 1812 :Description: Name of the file containing climate forcing fields. 1813 1814 #. :config:`ocean.given.period` (*integer*) 1815 1816 :Value: 0 1817 :Option: :opt:`-ocean_given_period` 1818 :Description: Length of the period of the climate forcing data. Set to zero to disable. 1819 1820 #. :config:`ocean.given.reference_year` (*integer*) 1821 1822 :Value: 0 1823 :Option: :opt:`-ocean_given_reference_year` 1824 :Description: Reference year to use when ``ocean.given.period`` is active. 1825 1826 #. :config:`ocean.melange_back_pressure_fraction` (*number*) 1827 1828 :Value: 0 (1) 1829 :Description: default melange back pressure fraction 1830 1831 #. :config:`ocean.models` (*string*) 1832 1833 :Value: constant 1834 :Option: :opt:`-ocean` 1835 :Description: Comma-separated list of ocean models and modifiers. 1836 1837 #. :config:`ocean.pico.continental_shelf_depth` (*number*) 1838 1839 :Value: -800 (meters) 1840 :Option: :opt:`-continental_shelf_depth` 1841 :Description: Determines the edge of the continental shelf to calculate mean ocean properties 1842 1843 #. :config:`ocean.pico.exclude_ice_rises` (*flag*) 1844 1845 :Value: yes 1846 :Option: :opt:`-exclude_icerises` 1847 :Description: Exclude ice rises for box calculation in PICO 1848 1849 #. :config:`ocean.pico.file` (*string*) 1850 1851 :Value: *no default* 1852 :Option: :opt:`-ocean_pico_file` 1853 :Description: Name of the file containing climate forcing fields. 1854 1855 #. :config:`ocean.pico.heat_exchange_coefficent` (*number*) 1856 1857 :Value: 0.000020 (meters second-1) 1858 :Option: :opt:`-gamma_T` 1859 :Description: Turbulent heat exchange coefficient 1860 1861 #. :config:`ocean.pico.maximum_ice_rise_area` (*number*) 1862 1863 :Value: 100000 (km2) 1864 :Description: Maximum ice rise area. Patches of grounded ice that are bugger than this are treated as continental ice sheets. 1865 1866 #. :config:`ocean.pico.number_of_boxes` (*integer*) 1867 1868 :Value: 5 1869 :Option: :opt:`-number_of_boxes` 1870 :Description: Default maximum number of boxes (for the largest ice shelves) 1871 1872 #. :config:`ocean.pico.overturning_coefficent` (*number*) 1873 1874 :Value: 1000000 (meters6 seconds-1 kg-1) 1875 :Option: :opt:`-overturning_coeff` 1876 :Description: Overturning stregth coefficient 1877 1878 #. :config:`ocean.pico.period` (*integer*) 1879 1880 :Value: 0 1881 :Option: :opt:`-ocean_pico_period` 1882 :Description: Length of the period of the climate forcing data. Set to zero to disable. 1883 1884 #. :config:`ocean.pico.reference_year` (*integer*) 1885 1886 :Value: 0 1887 :Option: :opt:`-ocean_pico_reference_year` 1888 :Description: Reference year to use when ``ocean.pico.period`` is active. 1889 1890 #. :config:`ocean.pik_melt_factor` (*number*) 1891 1892 :Value: 0.005000 (1) 1893 :Option: :opt:`-meltfactor_pik` 1894 :Description: dimensionless tuning parameter in the '-ocean pik' ocean heat flux parameterization; see :cite:`Martinetal2011` 1895 1896 #. :config:`ocean.sub_shelf_heat_flux_into_ice` (*number*) 1897 1898 :Value: 0.500000 (W meter-2) 1899 :Description: = J meter-2 second-1; naively chosen default value for heat from ocean; see comments in pism::ocean::Constant::shelf_base_mass_flux(). 1900 1901 #. :config:`ocean.th.file` (*string*) 1902 1903 :Value: *no default* 1904 :Option: :opt:`-ocean_th_file` 1905 :Description: Name of the file containing climate forcing fields. 1906 1907 #. :config:`ocean.th.period` (*integer*) 1908 1909 :Value: 0 1910 :Option: :opt:`-ocean_th_period` 1911 :Description: Length of the period of the climate forcing data. Set to zero to disable. 1912 1913 #. :config:`ocean.th.reference_year` (*integer*) 1914 1915 :Value: 0 1916 :Option: :opt:`-ocean_th_reference_year` 1917 :Description: Reference year to use when ``ocean.th.period`` is active. 1918 1919 #. :config:`ocean.three_equation_model_clip_salinity` (*flag*) 1920 1921 :Value: yes 1922 :Option: :opt:`-clip_shelf_base_salinity` 1923 :Description: Clip shelf base salinity so that it is in the range [4, 40] k/kg. See :cite:`HollandJenkins1999`. 1924 1925 #. :config:`output.ISMIP6` (*flag*) 1926 1927 :Value: false 1928 :Description: Follow ISMIP6 conventions (units, variable names, "standard names") when writing output variables. 1929 1930 #. :config:`output.ISMIP6_extra_variables` (*string*) 1931 1932 :Value: ``lithk, orog, topg, hfgeoubed, acabf, libmassbfgr, libmassbffl, dlithkdt, velsurf, zvelsurf, velbase, zvelbase, velmean, litemptop, litempbotgr, litempbotfl, strbasemag, licalvf, lifmassbf, sftgif, sftgrf, sftflf`` 1933 :Description: Comma-separated list of fields reported by models participating in ISMIP6 simulations. 1934 1935 #. :config:`output.ISMIP6_ts_variables` (*string*) 1936 1937 :Value: ``lim, limnsw, iareagr, iareafl, tendacabf, tendlibmassbf, tendlibmassbffl, tendlicalvf, tendlifmassbf`` 1938 :Description: Comma-separated list of scalar variables (time series) reported by models participating in ISMIP6 simulations. 1939 1940 #. :config:`output.backup_interval` (*number*) 1941 1942 :Value: 1 (hours) 1943 :Option: :opt:`-backup_interval` 1944 :Description: wall-clock time between automatic backups 1945 1946 #. :config:`output.backup_size` (*keyword*) 1947 1948 :Value: ``small`` 1949 :Choices: ``none, small, medium, big_2d, big`` 1950 :Option: :opt:`-backup_size` 1951 :Description: The 'size' of a backup file. See configuration parameters output.sizes.medium, output.sizes.big_2d, output.sizes.big 1952 1953 #. :config:`output.extra.append` (*flag*) 1954 1955 :Value: no 1956 :Option: :opt:`-extra_append` 1957 :Description: Append to an existing output file. 1958 1959 #. :config:`output.extra.file` (*string*) 1960 1961 :Value: *no default* 1962 :Option: :opt:`-extra_file` 1963 :Description: Name of the output file containing spatially-variable diagnostics. 1964 1965 #. :config:`output.extra.split` (*flag*) 1966 1967 :Value: no 1968 :Option: :opt:`-extra_split` 1969 :Description: Save spatially-variable diagnostics to separate files (one per time record). 1970 1971 #. :config:`output.extra.stop_missing` (*flag*) 1972 1973 :Value: yes 1974 :Option: :opt:`-extra_stop_missing` 1975 :Description: Stop if requested variable is not available instead of warning. 1976 1977 #. :config:`output.extra.times` (*string*) 1978 1979 :Value: *no default* 1980 :Option: :opt:`-extra_times` 1981 :Description: List or a range of times defining reporting intervals for spatially-variable diagnostics. 1982 1983 #. :config:`output.extra.vars` (*string*) 1984 1985 :Value: *no default* 1986 :Option: :opt:`-extra_vars` 1987 :Description: Comma-separated list of spatially-variable diagnostics. 1988 1989 #. :config:`output.file_name` (*string*) 1990 1991 :Value: unnamed.nc 1992 :Option: :opt:`-o` 1993 :Description: The file to save final model results to. 1994 1995 #. :config:`output.fill_value` (*number*) 1996 1997 :Value: -2.000000e+09 (none) 1998 :Description: _FillValue used when saving diagnostic quantities 1999 2000 #. :config:`output.format` (*keyword*) 2001 2002 :Value: ``netcdf3`` 2003 :Choices: ``netcdf3, netcdf4_parallel, pnetcdf, pio_pnetcdf, pio_netcdf4p, pio_netcdf4c, pio_netcdf`` 2004 :Option: :opt:`-o_format` 2005 :Description: The I/O format used for spatial fields; 'netcdf3' is the default, 'netcd4_parallel' is available if PISM was built with parallel NetCDF-4, and 'pnetcdf' is available if PISM was built with PnetCDF. 2006 2007 #. :config:`output.ice_free_thickness_standard` (*number*) 2008 2009 :Value: 10 (meters) 2010 :Description: If ice is thinner than this standard then a grid cell is considered ice-free for purposes of reporting glacierized area, volume, etc. 2011 2012 #. :config:`output.pio.base` (*integer*) 2013 2014 :Value: 0 2015 :Description: Rank of the first I/O task 2016 2017 #. :config:`output.pio.n_writers` (*integer*) 2018 2019 :Value: 1 2020 :Description: Number of I/O tasks to use 2021 2022 #. :config:`output.pio.stride` (*integer*) 2023 2024 :Value: 1 2025 :Description: Offset between I/O tasks 2026 2027 #. :config:`output.runtime.area_scale_factor_log10` (*integer*) 2028 2029 :Value: 6 2030 :Option: :opt:`-summary_area_scale_factor_log10` 2031 :Description: an integer; log base 10 of scale factor to use for area (in km^2) in summary line to stdout 2032 2033 #. :config:`output.runtime.time_unit_name` (*string*) 2034 2035 :Value: year 2036 :Description: Time units used when printing model time, time step, and maximum horizontal velocity at summary to stdout. Must be valid udunits for time. (E.g. choose from year,month,day,hour,minute,second.) 2037 2038 #. :config:`output.runtime.time_use_calendar` (*flag*) 2039 2040 :Value: yes 2041 :Description: Whether to use the current calendar when printing model time in summary to stdout. 2042 2043 #. :config:`output.runtime.viewer.size` (*integer*) 2044 2045 :Value: 320 2046 :Option: :opt:`-view_size` 2047 :Description: default diagnostic viewer size (number of pixels of the longer side) 2048 2049 #. :config:`output.runtime.viewer.variables` (*string*) 2050 2051 :Value: *no default* 2052 :Option: :opt:`-view` 2053 :Description: comma-separated list of map-plane diagnostic quantities to view at runtime 2054 2055 #. :config:`output.runtime.volume_scale_factor_log10` (*integer*) 2056 2057 :Value: 6 2058 :Option: :opt:`-summary_vol_scale_factor_log10` 2059 :Description: an integer; log base 10 of scale factor to use for volume (in km^3) in summary line to stdout 2060 2061 #. :config:`output.size` (*keyword*) 2062 2063 :Value: ``medium`` 2064 :Choices: ``none, small, medium, big_2d, big`` 2065 :Option: :opt:`-o_size` 2066 :Description: The 'size' of an output file. See configuration parameters output.sizes.medium, output.sizes.big_2d, output.sizes.big 2067 2068 #. :config:`output.sizes.big` (*string*) 2069 2070 :Value: ``cts, liqfrac, temp, temp_pa, uvel, vvel, wvel, wvel_rel`` 2071 :Description: Comma-separated list of variables to write to the output (in addition to model_state variables and variables listed in output.sizes.medium and output.sizes.big_2d) if 'big' output size is selected. Does not include fields written by sub-models. 2072 2073 #. :config:`output.sizes.big_2d` (*string*) 2074 2075 :Value: ``age, bfrict, bheatflx, bmelt, bwp, bwprel, dbdt, effbwp, enthalpybase, enthalpysurf, flux_divergence, hardav, hydroinput, lat, litho_temp, lon, nuH, rank, tempbase, tempicethk, tempicethk_basal, temppabase, tempsurf, thk, thksmooth, tillphi, topg, velbar, velbase, wallmelt, wvelbase`` 2076 :Description: Comma-separated list of variables to write to the output (in addition to model_state variables and variables listed in output.sizes.medium) if 'big_2d' output size is selected. Does not include fields written by boundary models. 2077 2078 #. :config:`output.sizes.medium` (*string*) 2079 2080 :Value: ``bwat, bwatvel, climatic_mass_balance, diffusivity, enthalpy, flux, flux_mag, ice_surface_temp, liqfrac, mask, schoofs_theta, strain_rates, taub_mag, tauc, taud_mag, temp_pa, tillwat, topgsmooth, usurf, velbar_mag, velbase_mag, velsurf, velsurf_mag, wvelsurf`` 2081 :Description: Comma-separated list of variables to write to the output (in addition to model_state variables) if 'medium' output size (the default) is selected. Does not include fields written by sub-models. 2082 2083 #. :config:`output.snapshot.file` (*string*) 2084 2085 :Value: *no default* 2086 :Option: :opt:`-save_file` 2087 :Description: Snapshot (output) file name (or prefix, if saving to individual files). 2088 2089 #. :config:`output.snapshot.size` (*keyword*) 2090 2091 :Value: ``small`` 2092 :Choices: ``none, small, medium, big_2d, big`` 2093 :Option: :opt:`-save_size` 2094 :Description: The 'size' of a snapshot file. See configuration parameters output.sizes.medium, output.sizes.big_2d, output.sizes.big 2095 2096 #. :config:`output.snapshot.split` (*flag*) 2097 2098 :Value: no 2099 :Option: :opt:`-save_split` 2100 :Description: Save model state snapshots to separate files (one per time record). 2101 2102 #. :config:`output.snapshot.times` (*string*) 2103 2104 :Value: *no default* 2105 :Option: :opt:`-save_times` 2106 :Description: List or a range of times to save model state snapshots at. 2107 2108 #. :config:`output.timeseries.append` (*flag*) 2109 2110 :Value: false 2111 :Option: :opt:`-ts_append` 2112 :Description: If true, append to the scalar time series output file. 2113 2114 #. :config:`output.timeseries.buffer_size` (*integer*) 2115 2116 :Value: 10000 2117 :Description: Number of scalar diagnostic time-series records to hold in memory before writing to disk. (PISM writes this many time-series records to reduce I/O costs.) Send the USR2 signal to flush time-series. 2118 2119 #. :config:`output.timeseries.filename` (*string*) 2120 2121 :Value: *no default* 2122 :Option: :opt:`-ts_file` 2123 :Description: Name of the file to save scalar time series to. Leave empty to disable reporting scalar time-series. 2124 2125 #. :config:`output.timeseries.times` (*string*) 2126 2127 :Value: *no default* 2128 :Option: :opt:`-ts_times` 2129 :Description: List or range of times defining reporting time intervals. 2130 2131 #. :config:`output.timeseries.variables` (*string*) 2132 2133 :Value: *no default* 2134 :Option: :opt:`-ts_vars` 2135 :Description: Requested scalar (time-series) diagnostics. Leave empty to save all available diagnostics. 2136 2137 #. :config:`output.use_MKS` (*flag*) 2138 2139 :Value: false 2140 :Description: Use MKS units in output files. 2141 2142 #. :config:`regional.no_model_strip` (*number*) 2143 2144 :Value: 5 (km) 2145 :Option: :opt:`-no_model_strip` 2146 :Description: Default width of the 'no model strip' in regional setups. 2147 2148 #. :config:`regional.no_model_yield_stress` (*number*) 2149 2150 :Value: 1000 (kPa) 2151 :Description: High yield stress used in the 'no_model_mask' area in the regional mode. 2152 2153 #. :config:`regional.zero_gradient` (*flag*) 2154 2155 :Value: false 2156 :Option: :opt:`-zero_grad_where_no_model` 2157 :Description: Use zero ice thickness and ice surface gradient in the no_model_mask area. 2158 2159 #. :config:`run_info.institution` (*string*) 2160 2161 :Value: *no default* 2162 :Option: :opt:`-institution` 2163 :Description: Institution name. This string is written to output files as the 'institution' global attribute. 2164 2165 #. :config:`run_info.title` (*string*) 2166 2167 :Value: *no default* 2168 :Option: :opt:`-title` 2169 :Description: Free-form string containing a concise description of the current run. This string is written to output files as the 'title' global attribute. 2170 2171 #. :config:`sea_level.models` (*string*) 2172 2173 :Value: constant 2174 :Option: :opt:`-sea_level` 2175 :Description: Comma-separated list of sea level models and modifiers. 2176 2177 #. :config:`stress_balance.calving_front_stress_bc` (*flag*) 2178 2179 :Value: no 2180 :Option: :opt:`-cfbc` 2181 :Description: Apply CFBC condition as in :cite:`Albrechtetal2011`, :cite:`Winkelmannetal2011`. May only apply to some stress balances; e.g. SSAFD as of May 2011. If not set then a strength-extension is used, as in :cite:`BBssasliding`. 2182 2183 #. :config:`stress_balance.ice_free_thickness_standard` (*number*) 2184 2185 :Value: 10 (meters) 2186 :Description: If ice is thinner than this standard then a cell is considered ice-free for purposes of computing ice velocity distribution. 2187 2188 #. :config:`stress_balance.model` (*keyword*) 2189 2190 :Value: ``sia`` 2191 :Choices: ``none, prescribed_sliding, weertman_sliding, sia, ssa, prescribed_sliding+sia, weertman_sliding+sia, ssa+sia`` 2192 :Option: :opt:`-stress_balance` 2193 :Description: Stress balance model 2194 2195 #. :config:`stress_balance.prescribed_sliding.file` (*string*) 2196 2197 :Value: *no default* 2198 :Description: The name of the file containing prescribed sliding velocity (variable names: `ubar`, `vbar`). 2199 2200 #. :config:`stress_balance.sia.Glen_exponent` (*number*) 2201 2202 :Value: 3 (pure number) 2203 :Option: :opt:`-sia_n` 2204 :Description: Glen exponent in ice flow law for SIA 2205 2206 #. :config:`stress_balance.sia.bed_smoother.range` (*number*) 2207 2208 :Value: 5000 (meters) 2209 :Option: :opt:`-bed_smoother_range` 2210 :Description: half-width of smoothing domain for stressbalance::BedSmoother, in implementing :cite:`Schoofbasaltopg2003` bed roughness parameterization for SIA; set value to zero to turn off mechanism 2211 2212 #. :config:`stress_balance.sia.bed_smoother.theta_min` (*number*) 2213 2214 :Value: 0 (1) 2215 :Description: minimum value of `\theta` in :cite:`Schoofbasaltopg2003` bed roughness parameterization for SIA 2216 2217 #. :config:`stress_balance.sia.e_age_coupling` (*flag*) 2218 2219 :Value: no 2220 :Option: :opt:`-e_age_coupling` 2221 :Description: Couple the SIA enhancement factor to age as in :cite:`Greve`. 2222 2223 #. :config:`stress_balance.sia.enhancement_factor` (*number*) 2224 2225 :Value: 1 (1) 2226 :Option: :opt:`-sia_e` 2227 :Description: Flow enhancement factor for SIA 2228 2229 #. :config:`stress_balance.sia.enhancement_factor_interglacial` (*number*) 2230 2231 :Value: 1 (1) 2232 :Option: :opt:`-sia_e_interglacial` 2233 :Description: Flow enhancement factor for SIA; used for ice accumulated during interglacial periods. 2234 2235 #. :config:`stress_balance.sia.flow_law` (*keyword*) 2236 2237 :Value: ``gpbld`` 2238 :Choices: ``arr, arrwarm, gk, gpbld, hooke, isothermal_glen, pb`` 2239 :Option: :opt:`-sia_flow_law` 2240 :Description: The SIA flow law. 2241 2242 #. :config:`stress_balance.sia.grain_size_age_coupling` (*flag*) 2243 2244 :Value: no 2245 :Option: :opt:`-grain_size_age_coupling` 2246 :Description: Use age of the ice to compute grain size to use with the Goldsby-Kohlstedt :cite:`GoldsbyKohlstedt` flow law 2247 2248 #. :config:`stress_balance.sia.limit_diffusivity` (*flag*) 2249 2250 :Value: no 2251 :Option: :opt:`-limit_sia_diffusivity` 2252 :Description: Limit SIA diffusivity by `stress_balance.sia.max_diffusivity`. 2253 2254 #. :config:`stress_balance.sia.max_diffusivity` (*number*) 2255 2256 :Value: 100 (m2 s-1) 2257 :Description: Maximum allowed diffusivity of the SIA flow. PISM stops with an error message if the SIA diffusivity exceeds this limit. 2258 2259 #. :config:`stress_balance.sia.surface_gradient_method` (*keyword*) 2260 2261 :Value: ``haseloff`` 2262 :Choices: ``eta, haseloff, mahaffy`` 2263 :Option: :opt:`-gradient` 2264 :Description: method used for surface gradient calculation at staggered grid points 2265 2266 #. :config:`stress_balance.ssa.Glen_exponent` (*number*) 2267 2268 :Value: 3 (pure number) 2269 :Option: :opt:`-ssa_n` 2270 :Description: Glen exponent in ice flow law for SSA 2271 2272 #. :config:`stress_balance.ssa.compute_surface_gradient_inward` (*flag*) 2273 2274 :Value: no 2275 :Description: If yes then use inward first-order differencing in computing surface gradient in the SSA objects. 2276 2277 #. :config:`stress_balance.ssa.dirichlet_bc` (*flag*) 2278 2279 :Value: no 2280 :Option: :opt:`-ssa_dirichlet_bc` 2281 :Description: apply SSA velocity Dirichlet boundary condition 2282 2283 #. :config:`stress_balance.ssa.enhancement_factor` (*number*) 2284 2285 :Value: 1 (1) 2286 :Option: :opt:`-ssa_e` 2287 :Description: Flow enhancement factor for SSA 2288 2289 #. :config:`stress_balance.ssa.enhancement_factor_interglacial` (*number*) 2290 2291 :Value: 1 (1) 2292 :Option: :opt:`-ssa_e_interglacial` 2293 :Description: Flow enhancement factor for SSA; used for ice accumulated during interglacial periods. 2294 2295 #. :config:`stress_balance.ssa.epsilon` (*number*) 2296 2297 :Value: 1.000000e+13 (Pascal second meter) 2298 :Option: :opt:`-ssa_eps` 2299 :Description: Initial amount of regularization in computation of product of effective viscosity and thickness (`\nu H`). This default value for `\nu H` comes e.g. from a hardness for the Ross ice shelf (`\bar B`) = 1.9e8 Pa `s^{1/3}` :cite:`MacAyealetal` and a typical strain rate of 0.001 1/year for the Ross ice shelf, giving `\nu = (\bar B) / (2 \cdot 0.001^{2/3})` = 9.49e+14 Pa s ~ 30 MPa year, the value in :cite:`Ritzetal2001`, but with a tiny thickness `H` of about 1 cm. 2300 2301 #. :config:`stress_balance.ssa.fd.brutal_sliding` (*flag*) 2302 2303 :Value: false 2304 :Option: :opt:`-brutal_sliding` 2305 :Description: Enhance sliding speed brutally. 2306 2307 #. :config:`stress_balance.ssa.fd.brutal_sliding_scale` (*number*) 2308 2309 :Value: 1 (1) 2310 :Option: :opt:`-brutal_sliding_scale` 2311 :Description: Brutal SSA Sliding Scale 2312 2313 #. :config:`stress_balance.ssa.fd.lateral_drag.enabled` (*flag*) 2314 2315 :Value: false 2316 :Description: set viscosity at ice shelf margin next to ice free bedrock as friction parameterization 2317 2318 #. :config:`stress_balance.ssa.fd.lateral_drag.viscosity` (*number*) 2319 2320 :Value: 5.000000e+15 (Pascal second) 2321 :Option: :opt:`-nu_bedrock` 2322 :Description: Staggered Viscosity used as side friction parameterization. 2323 2324 #. :config:`stress_balance.ssa.fd.max_iterations` (*integer*) 2325 2326 :Value: 300 2327 :Option: :opt:`-ssafd_picard_maxi` 2328 :Description: Maximum number of Picard iterations for the ice viscosity computation, in the SSAFD object 2329 2330 #. :config:`stress_balance.ssa.fd.max_speed` (*number*) 2331 2332 :Value: 300000 (km s-1) 2333 :Option: :opt:`-ssafd_max_speed` 2334 :Description: Upper bound for the ice speed computed by the SSAFD solver. 2335 2336 #. :config:`stress_balance.ssa.fd.nuH_iter_failure_underrelaxation` (*number*) 2337 2338 :Value: 0.800000 (pure number) 2339 :Option: :opt:`-ssafd_nuH_iter_failure_underrelaxation` 2340 :Description: In event of 'Effective viscosity not converged' failure, use outer iteration rule nuH <- nuH + f (nuH - nuH_old), where f is this parameter. 2341 2342 #. :config:`stress_balance.ssa.fd.relative_convergence` (*number*) 2343 2344 :Value: 0.000100 (1) 2345 :Option: :opt:`-ssafd_picard_rtol` 2346 :Description: Relative change tolerance for the effective viscosity in the SSAFD object 2347 2348 #. :config:`stress_balance.ssa.fd.replace_zero_diagonal_entries` (*flag*) 2349 2350 :Value: yes 2351 :Description: Replace zero diagonal entries in the SSAFD matrix with basal_resistance.beta_ice_free_bedrock to avoid solver failures. 2352 2353 #. :config:`stress_balance.ssa.flow_law` (*keyword*) 2354 2355 :Value: ``gpbld`` 2356 :Choices: ``arr, arrwarm, gpbld, hooke, isothermal_glen, pb`` 2357 :Option: :opt:`-ssa_flow_law` 2358 :Description: The SSA flow law. 2359 2360 #. :config:`stress_balance.ssa.method` (*keyword*) 2361 2362 :Value: ``fd`` 2363 :Choices: ``fd, fem`` 2364 :Option: :opt:`-ssa_method` 2365 :Description: Algorithm for computing the SSA solution. 2366 2367 #. :config:`stress_balance.ssa.read_initial_guess` (*flag*) 2368 2369 :Value: yes 2370 :Option: :opt:`-ssa_read_initial_guess` 2371 :Description: Read the initial guess from the input file when re-starting. 2372 2373 #. :config:`stress_balance.ssa.strength_extension.constant_nu` (*number*) 2374 2375 :Value: 9.486807e+14 (Pascal second) 2376 :Description: The SSA is made elliptic by use of a constant value for the product of viscosity (nu) and thickness (H). This value for nu comes from hardness (bar B)=1.9e8 `Pa s^{1/3}` :cite:`MacAyealetal` and a typical strain rate of 0.001 year-1: `\nu = (\bar B) / (2 \cdot 0.001^{2/3})`. Compare the value of 9.45e14 Pa s = 30 MPa year in :cite:`Ritzetal2001`. 2377 2378 #. :config:`stress_balance.ssa.strength_extension.min_thickness` (*number*) 2379 2380 :Value: 50 (meters) 2381 :Description: The SSA is made elliptic by use of a constant value for the product of viscosity (nu) and thickness (H). At ice thicknesses below this value the product nu*H switches from the normal vertical integral to a constant value. The geometry itself is not affected by this value. 2382 2383 #. :config:`stress_balance.vertical_velocity_approximation` (*keyword*) 2384 2385 :Value: ``centered`` 2386 :Choices: ``centered, upstream`` 2387 :Option: :opt:`-vertical_velocity_approximation` 2388 :Description: Vertical velocity FD approximation. "Upstream" uses first-order finite difference to compute u_x and v_y. Uses basal velocity to make decisions. 2389 2390 #. :config:`stress_balance.weertman_sliding.A` (*number*) 2391 2392 :Value: 1.800000e-16 (Pa-3 year-1 m-2) 2393 :Description: Sliding parameter in the Weertman-style sliding parameterization :cite:`Tomkin2007` 2394 2395 #. :config:`stress_balance.weertman_sliding.k` (*number*) 2396 2397 :Value: 0.200000 (1) 2398 :Description: The ratio of the basal water pressure and the ice overburden pressure in the Weertman-style sliding parameterization. 2399 2400 #. :config:`surface.anomaly.file` (*string*) 2401 2402 :Value: *no default* 2403 :Option: :opt:`-surface_anomaly_file` 2404 :Description: Name of the file containing climate forcing fields. 2405 2406 #. :config:`surface.anomaly.period` (*integer*) 2407 2408 :Value: 0 2409 :Option: :opt:`-surface_anomaly_period` 2410 :Description: Length of the period of the climate forcing data. Set to zero to disable. 2411 2412 #. :config:`surface.anomaly.reference_year` (*integer*) 2413 2414 :Value: 0 2415 :Option: :opt:`-surface_anomaly_reference_year` 2416 :Description: Reference year to use when ``surface.anomaly.period`` is active. 2417 2418 #. :config:`surface.cache.update_interval` (*integer*) 2419 2420 :Value: 10 2421 :Description: Update interval (in years) for the `-surface cache` modifier. 2422 2423 #. :config:`surface.delta_T.file` (*string*) 2424 2425 :Value: *no default* 2426 :Option: :opt:`-surface_delta_T_file` 2427 :Description: Name of the file containing temperature offsets. 2428 2429 #. :config:`surface.delta_T.period` (*integer*) 2430 2431 :Value: 0 2432 :Option: :opt:`-surface_delta_T_period` 2433 :Description: Length of the period of the climate forcing data. Set to zero to disable. 2434 2435 #. :config:`surface.delta_T.reference_year` (*integer*) 2436 2437 :Value: 0 2438 :Option: :opt:`-surface_delta_T_reference_year` 2439 :Description: Reference year to use when ``surface.delta_T.period`` is active. 2440 2441 #. :config:`surface.elevation_change.file` (*string*) 2442 2443 :Value: *no default* 2444 :Option: :opt:`-surface_elevation_change_file` 2445 :Description: Name of the file containing the reference surface elevation field (variable ``usurf``). 2446 2447 #. :config:`surface.elevation_change.period` (*integer*) 2448 2449 :Value: 0 2450 :Option: :opt:`-surface_elevation_change_period` 2451 :Description: Length of the period of the climate forcing data. Set to zero to disable. 2452 2453 #. :config:`surface.elevation_change.reference_year` (*integer*) 2454 2455 :Value: 0 2456 :Option: :opt:`-surface_elevation_change_reference_year` 2457 :Description: Reference year to use when ``surface.elevation_change.period`` is active. 2458 2459 #. :config:`surface.elevation_change.smb.exp_factor` (*number*) 2460 2461 :Value: 0 (Kelvin-1) 2462 :Option: :opt:`-smb_exp_factor` 2463 :Description: Exponential for the surface mass balance. 2464 2465 #. :config:`surface.elevation_change.smb.lapse_rate` (*number*) 2466 2467 :Value: 0 ((m / year) / km) 2468 :Option: :opt:`-smb_lapse_rate` 2469 :Description: Lapse rate for the surface mass balance. 2470 2471 #. :config:`surface.elevation_change.smb.method` (*keyword*) 2472 2473 :Value: ``shift`` 2474 :Choices: ``scale, shift`` 2475 :Option: :opt:`-smb_adjustment` 2476 :Description: Choose the SMB adjustment method. ``scale``: use temperature-change-dependent scaling factor. ``shift``: use the SMB lapse rate. 2477 2478 #. :config:`surface.elevation_change.temperature_lapse_rate` (*number*) 2479 2480 :Value: 0 (K / km) 2481 :Option: :opt:`-temp_lapse_rate` 2482 :Description: Lapse rate for the temperature at the top of the ice. 2483 2484 #. :config:`surface.force_to_thickness.alpha` (*number*) 2485 2486 :Value: 0.010000 (year-1) 2487 :Option: :opt:`-force_to_thickness_alpha` 2488 :Description: exponential coefficient in force-to-thickness mechanism 2489 2490 #. :config:`surface.force_to_thickness.ice_free_alpha_factor` (*number*) 2491 2492 :Value: 1 (1) 2493 :Option: :opt:`-force_to_thickness_ice_free_alpha_factor` 2494 :Description: surface.force_to_thickness.alpha is multiplied by this factor in areas that are ice-free according to the target ice thickness and surface.force_to_thickness.ice_free_thickness_threshold 2495 2496 #. :config:`surface.force_to_thickness.ice_free_thickness_threshold` (*number*) 2497 2498 :Value: 1 (meters) 2499 :Option: :opt:`-force_to_thickness_ice_free_thickness_threshold` 2500 :Description: threshold of ice thickness in the force-to-thickness target field. Used to determine whether to use surface.force_to_thickness.ice_free_alpha_factor. 2501 2502 #. :config:`surface.force_to_thickness.start_time` (*number*) 2503 2504 :Value: -4.540000e+09 (years) 2505 :Description: Starting time for the "force to thickness" modifier; the default is "start from the creation of the Earth." 2506 2507 #. :config:`surface.force_to_thickness_file` (*string*) 2508 2509 :Value: *no default* 2510 :Option: :opt:`-force_to_thickness_file` 2511 :Description: The name of the file to read the target ice thickness from. 2512 2513 #. :config:`surface.given.file` (*string*) 2514 2515 :Value: *no default* 2516 :Option: :opt:`-surface_given_file` 2517 :Description: Name of the file containing climate forcing fields. 2518 2519 #. :config:`surface.given.period` (*integer*) 2520 2521 :Value: 0 2522 :Option: :opt:`-surface_given_period` 2523 :Description: Length of the period of the climate forcing data. Set to zero to disable. 2524 2525 #. :config:`surface.given.reference_year` (*integer*) 2526 2527 :Value: 0 2528 :Option: :opt:`-surface_given_reference_year` 2529 :Description: Reference year to use when ``surface.given.period`` is active. 2530 2531 #. :config:`surface.given.smb_max` (*number*) 2532 2533 :Value: 91000 (kg m-2 year-1) 2534 :Description: Maximum climatic mass balance value (used to check input data). Corresponds to 100 m/year ice equivalent. 2535 2536 #. :config:`surface.ismip6.file` (*string*) 2537 2538 :Value: *no default* 2539 :Option: :opt:`-surface_ismip6_file` 2540 :Description: Name of the file containing climate forcing anomaly fields. 2541 2542 #. :config:`surface.ismip6.period` (*integer*) 2543 2544 :Value: 0 2545 :Option: :opt:`-surface_ismip6_period` 2546 :Description: Length of the period of the climate forcing data. Set to zero to disable. 2547 2548 #. :config:`surface.ismip6.reference_file` (*string*) 2549 2550 :Value: *no default* 2551 :Option: :opt:`-surface_ismip6_reference_file` 2552 :Description: Name of the file containing reference climate forcing fields. 2553 2554 #. :config:`surface.ismip6.reference_year` (*integer*) 2555 2556 :Value: 0 2557 :Description: Reference year to use when ``surface.ismip6.period`` is active. 2558 2559 #. :config:`surface.models` (*string*) 2560 2561 :Value: given 2562 :Option: :opt:`-surface` 2563 :Description: Comma-separated list of surface models and modifiers. 2564 2565 #. :config:`surface.pdd.air_temp_all_precip_as_rain` (*number*) 2566 2567 :Value: 275.150000 (Kelvin) 2568 :Description: threshold temperature above which all precipitation is rain; must exceed surface.pdd.air_temp_all_precip_as_snow to avoid division by zero, because difference is in a denominator 2569 2570 #. :config:`surface.pdd.air_temp_all_precip_as_snow` (*number*) 2571 2572 :Value: 273.150000 (Kelvin) 2573 :Description: threshold temperature below which all precipitation is snow 2574 2575 #. :config:`surface.pdd.balance_year_start_day` (*integer*) 2576 2577 :Value: 274 2578 :Description: day of year for October 1st, beginning of the balance year in northern latitudes. 2579 2580 #. :config:`surface.pdd.factor_ice` (*number*) 2581 2582 :Value: 0.008791 (meter / (Kelvin day)) 2583 :Description: EISMINT-Greenland value :cite:`RitzEISMINT`; = (8 mm liquid-water-equivalent) / (pos degree day) 2584 2585 #. :config:`surface.pdd.factor_snow` (*number*) 2586 2587 :Value: 0.003297 (meter / (Kelvin day)) 2588 :Description: EISMINT-Greenland value :cite:`RitzEISMINT`; = (3 mm liquid-water-equivalent) / (pos degree day) 2589 2590 #. :config:`surface.pdd.fausto.T_c` (*number*) 2591 2592 :Value: 272.150000 (Kelvin) 2593 :Description: = -1 + 273.15; for formula (6) in :cite:`Faustoetal2009` 2594 2595 #. :config:`surface.pdd.fausto.T_w` (*number*) 2596 2597 :Value: 283.150000 (Kelvin) 2598 :Description: = 10 + 273.15; for formula (6) in :cite:`Faustoetal2009` 2599 2600 #. :config:`surface.pdd.fausto.beta_ice_c` (*number*) 2601 2602 :Value: 0.015000 (meter / (Kelvin day)) 2603 :Description: water-equivalent thickness; for formula (6) in :cite:`Faustoetal2009` 2604 2605 #. :config:`surface.pdd.fausto.beta_ice_w` (*number*) 2606 2607 :Value: 0.007000 (meter / (Kelvin day)) 2608 :Description: water-equivalent thickness; for formula (6) in :cite:`Faustoetal2009` 2609 2610 #. :config:`surface.pdd.fausto.beta_snow_c` (*number*) 2611 2612 :Value: 0.003000 (meter / (Kelvin day)) 2613 :Description: water-equivalent thickness; for formula (6) in :cite:`Faustoetal2009` 2614 2615 #. :config:`surface.pdd.fausto.beta_snow_w` (*number*) 2616 2617 :Value: 0.003000 (meter / (Kelvin day)) 2618 :Description: water-equivalent thickness; for formula (6) in :cite:`Faustoetal2009` 2619 2620 #. :config:`surface.pdd.fausto.enabled` (*flag*) 2621 2622 :Value: false 2623 :Option: :opt:`-pdd_fausto` 2624 :Description: Set PDD parameters using formulas (6) and (7) in :cite:`Faustoetal2009` 2625 2626 #. :config:`surface.pdd.fausto.latitude_beta_w` (*number*) 2627 2628 :Value: 72 (degree_north) 2629 :Description: latitude below which to use warm case, in formula (6) in :cite:`Faustoetal2009` 2630 2631 #. :config:`surface.pdd.firn_compaction_to_accumulation_ratio` (*number*) 2632 2633 :Value: 0.750000 (1) 2634 :Description: How much firn as a fraction of accumulation is turned into ice 2635 2636 #. :config:`surface.pdd.firn_depth_file` (*string*) 2637 2638 :Value: *no default* 2639 :Option: :opt:`-pdd_firn_depth_file` 2640 :Description: The name of the file to read the firn_depth from. 2641 2642 #. :config:`surface.pdd.interpret_precip_as_snow` (*flag*) 2643 2644 :Value: no 2645 :Description: Interpret precipitation as snow fall. 2646 2647 #. :config:`surface.pdd.max_evals_per_year` (*integer*) 2648 2649 :Value: 52 2650 :Description: maximum number of times the PDD scheme will ask for air temperature and precipitation to build location-dependent time series for computing (expected) number of positive degree days and snow accumulation; the default means the PDD uses weekly samples of the annual cycle; see also surface.pdd.std_dev 2651 2652 #. :config:`surface.pdd.method` (*keyword*) 2653 2654 :Value: ``expectation_integral`` 2655 :Choices: ``expectation_integral, repeatable_random_process, random_process`` 2656 :Option: :opt:`-pdd_method` 2657 :Description: PDD implementation method 2658 2659 #. :config:`surface.pdd.positive_threshold_temp` (*number*) 2660 2661 :Value: 273.150000 (Kelvin) 2662 :Description: temperature used to determine meaning of 'positive' degree day 2663 2664 #. :config:`surface.pdd.refreeze` (*number*) 2665 2666 :Value: 0.600000 (1) 2667 :Description: EISMINT-Greenland value :cite:`RitzEISMINT` 2668 2669 #. :config:`surface.pdd.refreeze_ice_melt` (*flag*) 2670 2671 :Value: yes 2672 :Description: If set to 'yes', refreeze surface.pdd.refreeze fraction of melted ice, otherwise all of the melted ice runs off. 2673 2674 #. :config:`surface.pdd.std_dev` (*number*) 2675 2676 :Value: 5 (Kelvin) 2677 :Description: std dev of daily temp variation; = EISMINT-Greenland value :cite:`RitzEISMINT` 2678 2679 #. :config:`surface.pdd.std_dev.file` (*string*) 2680 2681 :Value: *no default* 2682 :Option: :opt:`-pdd_sd_file` 2683 :Description: The name of the file to read `air_temp_sd` (standard deviation of air temperature) from. 2684 2685 #. :config:`surface.pdd.std_dev.period` (*integer*) 2686 2687 :Value: 0 2688 :Option: :opt:`-pdd_sd_period` 2689 :Description: Length of the period of the climate forcing data. Set to zero to disable. 2690 2691 #. :config:`surface.pdd.std_dev.reference_year` (*integer*) 2692 2693 :Value: 0 2694 :Option: :opt:`-pdd_sd_reference_year` 2695 :Description: Reference year to use when ``surface.pdd.std_dev.period`` is active. 2696 2697 #. :config:`surface.pdd.std_dev_lapse_lat_base` (*number*) 2698 2699 :Value: 72 (degree_north) 2700 :Description: std_dev is a function of latitude, with value surface.pdd.std_dev at this latitude; this value only active if surface.pdd.std_dev_lapse_lat_rate is nonzero 2701 2702 #. :config:`surface.pdd.std_dev_lapse_lat_rate` (*number*) 2703 2704 :Value: 0 (Kelvin / degree_north) 2705 :Description: std_dev is a function of latitude, with rate of change with respect to latitude given by this constant 2706 2707 #. :config:`surface.pdd.std_dev_param_a` (*number*) 2708 2709 :Value: -0.150000 (pure number) 2710 :Description: Parameter a in Sigma = a*T + b, with T in degrees C. Used only if surface.pdd.std_dev_use_param is set to yes. 2711 2712 #. :config:`surface.pdd.std_dev_param_b` (*number*) 2713 2714 :Value: 0.660000 (Kelvin) 2715 :Description: Parameter b in Sigma = a*T + b, with T in degrees C. Used only if surface.pdd.std_dev_use_param is set to yes. 2716 2717 #. :config:`surface.pdd.std_dev_use_param` (*flag*) 2718 2719 :Value: no 2720 :Description: Parameterize standard deviation as a linear function of air temperature over ice-covered grid cells. The region of application is controlled by geometry.ice_free_thickness_standard. 2721 2722 #. :config:`surface.pressure` (*number*) 2723 2724 :Value: 0 (Pascal) 2725 :Description: atmospheric pressure; = pressure at ice surface 2726 2727 #. :config:`time.calendar` (*keyword*) 2728 2729 :Value: ``365_day`` 2730 :Choices: ``standard, gregorian, proleptic_gregorian, noleap, 365_day, 360_day, julian, none`` 2731 :Option: :opt:`-calendar` 2732 :Description: The calendar to use. 2733 2734 #. :config:`time.dimension_name` (*string*) 2735 2736 :Value: time 2737 :Description: The name of the time dimension in PISM output files. 2738 2739 #. :config:`time.eemian_end` (*number*) 2740 2741 :Value: -114500 (years) 2742 :Description: End of the Eemian interglacial period. See :cite:`Greve97Greenland`. 2743 2744 #. :config:`time.eemian_start` (*number*) 2745 2746 :Value: -132000 (years) 2747 :Description: Start of the Eemian interglacial period. See :cite:`Greve97Greenland`. 2748 2749 #. :config:`time.holocene_start` (*number*) 2750 2751 :Value: -11000 (years) 2752 :Description: Start of the Holocene interglacial period. See :cite:`Greve97Greenland`. 2753 2754 #. :config:`time.reference_date` (*string*) 2755 2756 :Value: 1-1-1 2757 :Description: year-month-day; reference date used for calendar computations and in PISM output files 2758 2759 #. :config:`time.run_length` (*number*) 2760 2761 :Value: 1000 (years) 2762 :Description: Default run length 2763 2764 #. :config:`time.start_year` (*number*) 2765 2766 :Value: 0 (years) 2767 :Description: Start year. 2768 2769 #. :config:`time_stepping.adaptive_ratio` (*number*) 2770 2771 :Value: 0.120000 (1) 2772 :Option: :opt:`-adapt_ratio` 2773 :Description: Adaptive time stepping ratio for the explicit scheme for the mass balance equation; :cite:`BBL`, inequality (25) 2774 2775 #. :config:`time_stepping.count_steps` (*flag*) 2776 2777 :Value: no 2778 :Option: :opt:`-count_steps` 2779 :Description: If yes, IceModel::run() will count the number of time steps it took. Sometimes useful for performance evaluation. Counts all steps, regardless of whether processes (mass continuity, energy, velocity, ...) occurred within the step. 2780 2781 #. :config:`time_stepping.hit_extra_times` (*flag*) 2782 2783 :Value: yes 2784 :Option: :opt:`-extra_force_output_times` 2785 :Description: Modify the time-stepping mechanism to hit times requested using -extra_times. 2786 2787 #. :config:`time_stepping.hit_multiples` (*number*) 2788 2789 :Value: 0 (years) 2790 :Option: :opt:`-timestep_hit_multiples` 2791 :Description: Hit every X years, where X is specified using this parameter. Use 0 to disable 2792 2793 #. :config:`time_stepping.hit_save_times` (*flag*) 2794 2795 :Value: no 2796 :Option: :opt:`-save_force_output_times` 2797 :Description: Modify the time-stepping mechanism to hit times requested using -save_times. 2798 2799 #. :config:`time_stepping.hit_ts_times` (*flag*) 2800 2801 :Value: no 2802 :Description: Modify the time-stepping mechanism to hit times requested using -ts_times. 2803 2804 #. :config:`time_stepping.maximum_time_step` (*number*) 2805 2806 :Value: 60 (years) 2807 :Option: :opt:`-max_dt` 2808 :Description: Maximum allowed time step length 2809 2810 #. :config:`time_stepping.skip.enabled` (*flag*) 2811 2812 :Value: no 2813 :Option: :opt:`-skip` 2814 :Description: Use the temperature, age, and SSA stress balance computation skipping mechanism. 2815 2816 #. :config:`time_stepping.skip.max` (*integer*) 2817 2818 :Value: 10 2819 :Option: :opt:`-skip_max` 2820 :Description: Number of mass-balance steps, including SIA diffusivity updates, to perform before a the temperature, age, and SSA stress balance computations are done