src/pism_config.cdl

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netcdf pism_config {
    variables:
    byte pism_config;

    // boolean flags:

    pism_config:force_output_times = "yes";
    pism_config:force_output_times_doc = "Modify the time-stepping mechanism to hit times requested using -extra_times and -ts_times.";

    pism_config:interpret_precip_as_snow = "no";
    pism_config:interpret_precip_as_snow_doc = "Interpret precipitation as snow fall.";

    pism_config:do_cold_ice_methods = "no";
    pism_config:do_cold_ice_methods_doc = "Use cold ice (i.e. not polythermal) methods.";

    pism_config:do_mass_conserve = "yes";
    pism_config:do_mass_conserve_doc = "Solve the mass conservation equation";

    pism_config:do_energy = "yes";
    pism_config:do_energy_doc = "Solve energy conservation equations.";

    pism_config:do_age = "no";
    pism_config:do_age_doc = "Solve age equation (advection equation for ice age).";

    pism_config:do_sia = "yes";
    pism_config:do_sia_doc = "Use the SIA stress balance (possibly as a part of a hybrid).";

    pism_config:do_skip = "no";
    pism_config:do_skip_doc = "Use the temperature, age, and SSA stress balance computation skipping mechanism.";

    pism_config:count_time_steps = "no";
    pism_config:count_time_steps_doc = "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.";

    pism_config:ssa_method = "fd";
    pism_config:ssa_method_doc = "Algorithm for computing the SSA solution; choose from 'fd' and 'fem'.";

    pism_config:use_ssa_when_grounded = "no";
    pism_config:use_ssa_when_grounded_doc = "The SSA can be used as a sliding law for grounded ice [\\ref BBssasliding], and it is if this is yes.";

    pism_config:do_pseudo_plastic_till = "no";
    pism_config:do_pseudo_plastic_till_doc = "Use the pseudo-plastic till model.";

    pism_config:calving_front_stress_boundary_condition = "no";
    pism_config:calving_front_stress_boundary_condition_doc = "Apply CFBC condition as in [\\ref Albrechtetal2011, \\ref Winkelmannetal2010TCD].  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 [\\ref BBssasliding].";

    pism_config:part_grid = "no";
    pism_config:part_grid_doc = "apply partially filled grid cell scheme";

    pism_config:part_redist = "no";
    pism_config:part_redist_doc = "for partially filled grid cell scheme, redistribute residuals Hresidual";

    pism_config:kill_icebergs = "no";
    pism_config:kill_icebergs_doc = "identify and kill detached ice-shelf areas";
    
    pism_config:do_eigen_calving = "false";
    pism_config:do_eigen_calving_doc = "calculate strain rates and related calving rate";
    
    pism_config:do_thickness_calving = "false";
    pism_config:do_thickness_calving_doc = "ad hoc calving at certain threshold for terminal ice thickness";
    
    pism_config:thermal_bedrock = "yes";
    pism_config:thermal_bedrock_doc = "Use the bedrock thermal model";

    pism_config:bed_deformation_model = "none";
    pism_config:bed_deformation_model_doc = "Selects a bed deformation model to use; possible choices are 'none', 'iso' (point-wise isostasy), 'lc' (see [\\ref LingleClark], requires FFTW3).";

    pism_config:ocean_kill  = "false";
    pism_config:ocean_kill_doc = "If used with input from a NetCDF initialization file which has ice-free ocean mask, will zero out ice thicknesses in areas that were ice-free ocean at time zero. This is calving at the location of the original calving front.";

    pism_config:floating_ice_killed = "false";
    pism_config:floating_ice_killed_doc = "If ice is (or becomes) floating then it is set to thickness zero. This is calving at the grounding line.";

    pism_config:is_dry_simulation = "no";
    pism_config:is_dry_simulation_doc = "Dry (ocean-less) simulation";

    pism_config:use_ssa_velocity = "no";
    pism_config:use_ssa_velocity_doc = "Use the equations of the shallow shelf approximation [\\ref MacAyeal, \\ref Morland, \\ref SchoofStream, \\ref WeisGreveHutter] for ice shelves and dragging ice shelves (%i.e. ice streams) where so-indicated by the mask";

    pism_config:write_ssa_system_to_matlab = "no";
    pism_config:write_ssa_system_to_matlab_doc = "Specifies whether to write the SSA system to a matlab file";

    pism_config:do_ssa_enhancement = "no";
    pism_config:do_ssa_enhancement_doc = "Set an enhancement factor for SSA-calculation.";

    pism_config:include_bmr_in_continuity = "yes";
    pism_config:include_bmr_in_continuity_doc = "Include basal melt rate in the continuity equation";

    pism_config:use_constant_nuh_for_ssa = "no";
    pism_config:use_constant_nuh_for_ssa_doc = "Compute velocities in ice shelves and streams with a constant value for the product of viscosity \\f$\\nu\\f$ and thickness \\f$H\\f$, obtained from the shelf extension";

    pism_config:compute_surf_grad_inward_ssa = "no";

    pism_config:force_full_diagnostics = "no";
    pism_config:force_full_diagnostics_doc = "Force full diagnostic output (adds 3D velocity fields and velocity components at the surface";

        pism_config:dirichlet_bc = "no";
        pism_config:dirichlet_bc_doc = "apply Dirichlet boundary condition";


    // parameters:

        pism_config:bootstrapping_BCMask_value_no_var = 0.0;
        pism_config:bootstrapping_BCMask_value_no_var_doc = "; mask for dirichlet boundary condition";
     
        pism_config:bootstrapping_BCvel_value_no_var = 100.0;
        pism_config:bootstrapping_BCvel_value_no_var_doc = "; dirichlet boundary condition";


    pism_config:bootstrapping_H_value_no_var = 0.0;
    pism_config:bootstrapping_H_value_no_var_doc = "m; thickness value to use if thk (land_ice_thickness) variable is absent in bootstrapping file";
    
    pism_config:bootstrapping_bed_value_no_var = 1.0;
    pism_config:bootstrapping_bed_value_no_var_doc = "m; bed elevation value to use if topg (bedrock_altitude) variable is absent in bootstrapping file";
    
    pism_config:bootstrapping_geothermal_flux_value_no_var = 0.042;
    pism_config:bootstrapping_geothermal_flux_value_no_var_doc = "W m-2; geothermal flux value to use if bheatflx variable is absent in bootstrapping file";
    
    pism_config:bootstrapping_uplift_value_no_var = 0.0;
    pism_config:bootstrapping_uplift_value_no_var_doc = "m s-1; uplift value to use if dbdt variable is absent in bootstrapping file";
    
    pism_config:bootstrapping_Hmelt_value_no_var = 0.0;
    pism_config:bootstrapping_Hmelt_value_no_var_doc = "m; basal melt water effective thickness value to use if variable Hmelt is absent in bootstrapping file";
    
    pism_config:bootstrapping_bmelt_value_no_var = 0.0;
    pism_config:bootstrapping_bmelt_value_no_var_doc = "m s-1; basal melt rate value to use if variable bmelt is absent in bootstrapping file";
    
    pism_config:bootstrapping_tillphi_value_no_var = 15.0;
    pism_config:bootstrapping_tillphi_value_no_var_doc = "degrees; till friction angle value to use if variable tillphi is absent in bootstrapping file; tends not to slip";
    
    pism_config:enhancement_factor = 1.0;
    pism_config:enhancement_factor_doc = "; Flow enhancement factor for SIA";
    
    pism_config:ssa_enhancement_factor = 1.0;
    pism_config:ssa_enhancement_factor_doc = "; Flow enhancement factor for SSA";

    pism_config:constant_grain_size = 1.0;
    pism_config:constant_grain_size_doc = "mm; Default constant grains size to use with the Goldsby-Kohlstedt [\\ref GoldsbyKohlstedt] flow law";

    pism_config:compute_grain_size_using_age = "no";
    pism_config:compute_grain_size_using_age_doc = "Use age of the ice to compute grain size to use with the Goldsby-Kohlstedt [\\ref GoldsbyKohlstedt] flow law";

    pism_config:start_year = 0;
    pism_config:start_year_doc = "years; Start year.";

    pism_config:run_length_years = 1000;
    pism_config:run_length_years_doc = "years; Default run length";

    pism_config:adaptive_timestepping_ratio = 0.12;
    pism_config:adaptive_timestepping_ratio_doc = "; Adaptive time stepping ratio for the explicit scheme for the mass balance equation; \\ref BBL, inequality (25)";

    pism_config:initial_age_of_ice_years = 0.0;
    pism_config:initial_age_of_ice_years_doc = "years; Initial age of ice";

    pism_config:maximum_time_step_years = 60.0;
    pism_config:maximum_time_step_years_doc = "years; Maximum allowed time step length";

    pism_config:epsilon_ssafd = 1.0e15;
    pism_config:epsilon_ssafd_doc = "initial amount of (denominator) regularization in computation of effective viscosity, in SSAFD object";

    pism_config:min_thickness_strength_extension_ssa = 50.0;
    pism_config:min_thickness_strength_extension_ssa_doc = "m; 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.";

    pism_config:constant_nu_strength_extension_ssa = 9.48680701906572e+14;
    pism_config:constant_nu_strength_extension_ssa_doc = "Pa s; 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) [\\ref MacAyealetal] and a typical strain rate of 0.001 a-1:  nu = (bar B) / (2 * 0.001^(2/3)).  Compare the value of 9.45e14 Pa s = 30 MPa yr in [\\ref Ritzetal2001].";

    pism_config:default_tauc = 2e5;
    pism_config:default_tauc_doc = "Pa; fill value for yield stress for basal till (plastic or pseudo-plastic model); note 2 x 10^5 Pa = 2.0 bar is quite strong and little sliding should occur without an explicit tauc choice altering this default";

    pism_config:sliding_scale_factor_reduces_tauc = -1.0;
    pism_config:sliding_scale_factor_reduces_tauc_doc = "; 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";

    pism_config:beta_ice_free_bedrock = 1.8e9;
    pism_config:beta_ice_free_bedrock_doc = "Pa s m-1; value is for ice stream E from [\ref HulbeMacAyeal]; thus sliding velocity, but we hope it doesn't matter much; at 100 m a-1 the linear sliding law gives 57040 Pa basal shear stress";
    
    pism_config:hmelt_max = 2.0;
    pism_config:hmelt_max_doc = "meters; maximum thickness of the basal melt water layer";

    pism_config:hmelt_decay_rate = 3.16887646154128e-11;
    pism_config:hmelt_decay_rate_doc = "m s-1; = 1 m per 1000 years; rate at which bwat is reduced to zero, in absence of other effects like basal melt rate";

    pism_config:minimum_temperature_for_sliding = 273.0;
    pism_config:minimum_temperature_for_sliding_doc = "K; This is less than water_melting_point_temperature.  If ice base is above this value then decide to do SIA sliding, if that mechanism is active at all.";

    pism_config:skip_max = 10;
    pism_config:skip_max_doc = "Number of mass-balance steps, including SIA diffusivity updates, to perform before a the temperature, age, and SSA stress balance computations are done";

    pism_config:default_till_phi = 30.0;
    pism_config:default_till_phi_doc = "degrees; fill value for till friction angle";

    pism_config:till_pw_fraction = 0.95;
    pism_config:till_pw_fraction_doc = "pure number; pore water pressure is this fraction of overburden";

    pism_config:till_c_0 = 0.0;
    pism_config:till_c_0_doc = "kPa; cohesion of till; 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...'";

    pism_config:bmr_enhance_basal_water_pressure = "no";
    pism_config:bmr_enhance_basal_water_pressure_doc = "if 'yes' then add basal melt rate enhancement to determination of basal water pressure, which normally only depends on effective thickness of basal water (=bwat)";

    pism_config:bmr_enhance_scale = 3.16887646154128e-7;
    pism_config:bmr_enhance_scale_doc = "m s-1; = 10.0 m a-1; level at which basal melt rate starts making major difference in water pressure";

    pism_config:thk_eff_basal_water_pressure = "no";
    pism_config:thk_eff_basal_water_pressure_doc = "if 'yes' then modeled basal water pressure experiences decreases at locations where thickness is smaller than thk_eff_H_high (typically near margin; thickness is surrogate for distance to margin)";

    pism_config:thk_eff_H_high = 2000.0;
    pism_config:thk_eff_H_high_doc = "m; maximum thickness at which thickness effect on basal water pressure is applied";

    pism_config:thk_eff_H_low = 1000.0;
    pism_config:thk_eff_H_low_doc = "m; thickness at which thickness effect on basal water pressure is full strength";

    pism_config:thk_eff_reduced = 0.97;
    pism_config:thk_eff_reduced_doc = "; factor by which basal water pressure is reduced by thickness effect";

    pism_config:mu_sliding = 0.0;
    pism_config:mu_sliding_doc = "The sliding law parameter in SIA sliding paradigm. <i>This kind of sliding is not recommended, which is why it is turned off by default.</i>  See Appendix B of \\ref BBssasliding for the dangers in this mechanism.";

    pism_config:bed_def_interval_years = 10.0;
    pism_config:bed_def_interval_years_doc = "years; Interval between bed deformation updates";

    pism_config:bed_smoother_range = 5.0e3;
    pism_config:bed_smoother_range_doc = "m; half-width of smoothing domain for PISMBedSmoother, in implementing [\\ref Schoofbasaltopg2003] bed roughness parameterization for SIA; set value to zero to turn off mechanism";

    pism_config:max_iterations_ssafd = 300;
    pism_config:max_iterations_ssafd_doc = "Maximum number of iterations for the ice viscosity computation, in the SSAFD object";

    pism_config:global_min_allowed_temp = 200.0;
    pism_config:global_min_allowed_temp_doc = "Kelvin; Minimum allowed ice temperature";

    pism_config:max_low_temp_count = 10;
    pism_config:max_low_temp_count_doc = "Maximum number of grid points with ice temperature below global_min_allowed_temp.";

    pism_config:eigen_calving = 0.0;
    pism_config:eigen_calving_doc = "Set proportionality constant to determine calving rate from strain rates";

    pism_config:calving_at_thickness = 50.0;
    pism_config:calving_at_thickness_doc = "When terminal ice thickness of floating ice shelf is less than this threshold, it will be calved off.";


    // for next constants, note (VELOCITY/LENGTH)^2  is very close to 10^-27; compare "\epsilon^2/L^2" which
    // appears in formula (4.1) in C. Schoof 2006 "A variational approach to ice streams" J Fluid Mech 556 pp 227--251
    pism_config:plastic_regularization = 0.01;
    pism_config:plastic_regularization_doc = "Set the value of \\f$\\epsilon\\f$ regularization of plastic till; this is the second \\f$\\epsilon\\f$ in formula (4.1) in [\\ref SchoofStream]";

    pism_config:pseudo_plastic_q = 0.25;
    pism_config:pseudo_plastic_q_doc = "; The exponent of the pseudo-plastic basal resistance model";

    pism_config:pseudo_plastic_uthreshold = 100.0;
    pism_config:pseudo_plastic_uthreshold_doc = "m a-1; ";

    pism_config:ssafd_relative_convergence = 1.0e-4;
    pism_config:ssafd_relative_convergence_doc = "Relative change tolerance for the effective viscosity in the SSAFD object";


   // PISMAtmosphereModel and PISMSurfaceModel and PSModifier and LocalMassBalance constants

    pism_config:pdd_max_temperature_evals_per_year = 53;
    pism_config:pdd_max_temperature_evals_per_year_doc = "integer; maximum number of times the PDD scheme will ask for temperatures to build location-dependent time series for computing (expected) number of positive degree days; the default means the PDD uses weekly samples of the annual cycle; see also pdd_std_dev";

    pism_config:pdd_positive_threshold_temp = 273.15;
    pism_config:pdd_positive_threshold_temp_doc = "K; temperature used to determine meaning of 'positive' degree day";

    pism_config:pdd_factor_snow = 0.003;
    pism_config:pdd_factor_snow_doc = "m K-1 day-1; EISMINT-Greenland value [\\ref RitzEISMINT] ; = (3 mm ice-equivalent) / (pos degree day)";

    pism_config:pdd_factor_ice = 0.008;
    pism_config:pdd_factor_ice_doc = "m K-1 day-1; EISMINT-Greenland value [\\ref RitzEISMINT] ; = (8 mm ice-equivalent) / (pos degree day)";

    pism_config:pdd_refreeze = 0.6;
    pism_config:pdd_refreeze_doc = "pure fraction; EISMINT-Greenland value [\\ref RitzEISMINT] ";

    pism_config:pdd_std_dev = 2.53;
    pism_config:pdd_std_dev_doc = "K; std dev of daily temp variation; value from [\\ref Faustoetal2009]; compare EISMINT-Greenland value of 5.0 [\\ref RitzEISMINT] ";

    pism_config:pdd_std_dev_lapse_lat_base = 72.0;
    pism_config:pdd_std_dev_lapse_lat_base_doc = "degrees_north; std_dev is a function of latitude, with value pdd_std_dev at this latitude; this value only active if pdd_std_dev_lapse_lat_rate is nonzero ";

    pism_config:pdd_std_dev_lapse_lat_rate = 0.0;
    pism_config:pdd_std_dev_lapse_lat_rate_doc = "K degrees_north-1; std_dev is a function of latitude, with rate of change with respect to latitude given by this constant ";

    pism_config:pdd_fausto_latitude_beta_w = 72.0;
    pism_config:pdd_fausto_latitude_beta_w_doc = "degrees N; latitude below which to use warm case, in formula (6) in [\\ref Faustoetal2009] ";

    pism_config:pdd_fausto_beta_ice_w = 0.007;
    pism_config:pdd_fausto_beta_ice_w_doc = "m day-1 K-1; water-equivalent thickness; for formula (6) in [\\ref Faustoetal2009] ";

    pism_config:pdd_fausto_beta_snow_w = 0.003;
    pism_config:pdd_fausto_beta_snow_w_doc = "m day-1 K-1; water-equivalent thickness; for formula (6) in [\\ref Faustoetal2009] ";

    pism_config:pdd_fausto_beta_ice_c = 0.015;
    pism_config:pdd_fausto_beta_ice_c_doc = "m day-1 K-1; water-equivalent thickness; for formula (6) in [\\ref Faustoetal2009] ";

    pism_config:pdd_fausto_beta_snow_c = 0.003;
    pism_config:pdd_fausto_beta_snow_c_doc = "m day-1 K-1; water-equivalent thickness; for formula (6) in [\\ref Faustoetal2009] ";

    pism_config:pdd_fausto_T_w = 283.15;
    pism_config:pdd_fausto_T_w_doc = "Kelvin; = 10 + 273.15; for formula (6) in [\\ref Faustoetal2009] ";

    pism_config:pdd_fausto_T_c = 272.15;
    pism_config:pdd_fausto_T_c_doc = "Kelvin; = -1 + 273.15; for formula (6) in [\\ref Faustoetal2009] ";

    pism_config:pdd_limit_timestep = "false";
    pism_config:pdd_limit_timestep_doc = "Limit PDD time-step to 1 year; used by pclimate to make long runs faster. Is not and should not be used elsewhere.";

    pism_config:snow_temp_fausto_d_ma = 314.98;
    pism_config:snow_temp_fausto_d_ma_doc = "K; = 41.83+273.15; base temperature for formula (1) in [\\ref Faustoetal2009] ";

    pism_config:snow_temp_fausto_gamma_ma = -0.006309;
    pism_config:snow_temp_fausto_gamma_ma_doc = "Kelvin m-1; = -6.309 / 1km; mean slope lapse rate for formula (1) in [\\ref Faustoetal2009] ";

    pism_config:snow_temp_fausto_c_ma = -0.7189;
    pism_config:snow_temp_fausto_c_ma_doc = "Kelvin (degN)-1; latitude-dependence coefficient for formula (1) in [\\ref Faustoetal2009] ";

    pism_config:snow_temp_fausto_kappa_ma = 0.0672;
    pism_config:snow_temp_fausto_kappa_ma_doc = "Kelvin (degW)-1; longitude-dependence coefficient for formula (1) in [\\ref Faustoetal2009] ";

    pism_config:snow_temp_fausto_d_mj = 287.85;
    pism_config:snow_temp_fausto_d_mj_doc = "Kelvin; = 14.70+273.15; base temperature for formula (2) in [\\ref Faustoetal2009] ";

    pism_config:snow_temp_fausto_gamma_mj = -0.005426;
    pism_config:snow_temp_fausto_gamma_mj_doc = "Kelvin m-1; = -5.426 / 1km; mean slope lapse rate for formula (2) in [\\ref Faustoetal2009] ";

    pism_config:snow_temp_fausto_c_mj = -0.1585;
    pism_config:snow_temp_fausto_c_mj_doc = "Kelvin (degN)-1; latitude-dependence coefficient for formula (2) in [\\ref Faustoetal2009] ";

    pism_config:snow_temp_fausto_kappa_mj = 0.0518;
    pism_config:snow_temp_fausto_kappa_mj_doc = "Kelvin (degW)-1; longitude-dependence coefficient for formula (2) in [\\ref Faustoetal2009] ";

    pism_config:snow_temp_july_day = 196;
    pism_config:snow_temp_july_day_doc = "day; = day of year for July 15; used in corrected formula (4) in [\\ref Faustoetal2009] ";

    pism_config:air_temp_all_precip_as_snow = 272.15;
    pism_config:air_temp_all_precip_as_snow_doc = "Kelvin; threshold temperature below which all precipitation is snow";

    pism_config:air_temp_all_precip_as_rain = 274.15;
    pism_config:air_temp_all_precip_as_rain_doc = "Kelvin; threshold temperature above which all precipitation is rain; must exceed air_temp_all_precip_as_snow to avoid division by zero, because difference is in a denominator";

    pism_config:precip_exponential_factor_for_temperature = 0.07041666667;
    pism_config:precip_exponential_factor_for_temperature_doc = "Kelvin-1; = 0.169/2.4; in SeaRISE-Greenland formula for paleo-precipitation from present; a 7.3\% change of precipitation rate for every one degC of temperature change [\\ref Huybrechts02] ";

    pism_config:force_to_thickness_alpha = 6.33775292816370e-11;
    pism_config:force_to_thickness_alpha_doc = "s-1; = 0.002 a-1; exponential coefficient in force-to-thickness mechanism";


    // PISMOceanModel constants

    pism_config:ocean_sub_shelf_heat_flux_into_ice = 0.5;
    pism_config:ocean_sub_shelf_heat_flux_into_ice_doc = "W m-2; = J m-2 s-1; naively chosen default value for heat from ocean; see comments in src/coupler/PISMOcean.cc";


    // THESE CONSTANTS MAY DUPLICATE, AND MAY SUPERSEDE, CONSTANTS IN materials.cc

    pism_config:beta_CC = 7.9e-8;
    pism_config:beta_CC_doc = "K Pa-1; Clausius-Clapeyron constant [\\ref Luethi2002]";

    pism_config:surface_pressure = 0.0;
    pism_config:surface_pressure_doc = "Pa; atmospheric pressure; = pressure at ice surface";

    pism_config:water_melting_point_temperature = 273.15;
    pism_config:water_melting_point_temperature_doc = "K; melting point of pure water";
 
    pism_config:enthalpy_converter_reference_temperature = 223.15;
    pism_config:enthalpy_converter_reference_temperature_doc = "K; = T_0 in enthalpy formulas in [\\ref AschwandenBuelerKhroulevBlatter]";

    pism_config:water_latent_heat_fusion = 3.34e5;
    pism_config:water_latent_heat_fusion_doc = "J kg-1; latent heat of fusion for water [\\ref AschwandenBlatter]";

    pism_config:water_specific_heat_capacity = 4170.0;
    pism_config:water_specific_heat_capacity_doc = "J kg-1 Kelvin-1; at melting point T_0 [\\ref AschwandenBlatter]";

    pism_config:ice_density = 910.0;
    pism_config:ice_density_doc = "kg m-3; = rho_i; density of ice in ice sheet";

    pism_config:ice_thermal_conductivity = 2.10;
    pism_config:ice_thermal_conductivity_doc = "J m-1 K-1 s-1; = W m-1 K-1";

    pism_config:ice_specific_heat_capacity = 2009.0;
    pism_config:ice_specific_heat_capacity_doc = "J kg-1 K-1; at melting point T_0";

    pism_config:Glen_exponent = 3.0;
    pism_config:Glen_exponent_doc = "; Glen exponent in ice flow law";

    pism_config:ice_softness = 4e-25;
    pism_config:ice_softness_doc = "Pa-3 s-1; ice softness used by CustomGlenIce";

    pism_config:Hooke_A = 4.42165e-9;
    pism_config:Hooke_A_doc = "s-1 Pa-3; A_Hooke = (1/B_0)^n where n=3 and B_0 = 1.928 a^(1/3) Pa. See [\\ref Hooke]";

    pism_config:Hooke_Q = 7.88e4;
    pism_config:Hooke_Q_doc = "J / mol; Activation energy, see [\\ref Hooke]";

    pism_config:Hooke_C = 0.16612;
    pism_config:Hooke_C_doc = "Kelvin^Hooke_k; See [\\ref Hooke]";

    pism_config:Hooke_k = 1.17;
    pism_config:Hooke_k_doc = "; See [\\ref Hooke]";

    pism_config:Hooke_Tr = 273.39;
    pism_config:Hooke_Tr_doc = "Kelvin; See [\\ref Hooke]";

    pism_config:Schoof_regularizing_length = 1000.0;
    pism_config:Schoof_regularizing_length_doc = "km; Regularizing length (Schoof definition)";

    pism_config:Schoof_regularizing_velocity = 1.0;
    pism_config:Schoof_regularizing_velocity_doc = "m/year; Regularizing velocity (Schoof definition)";

    pism_config:Paterson-Budd_A_cold = 3.61e-13;
    pism_config:Paterson-Budd_A_cold_doc = "Pa^-3 / s; Paterson-Budd A_cold, see [\\ref PatersonBudd]";

    pism_config:Paterson-Budd_A_warm = 1.73e3;
    pism_config:Paterson-Budd_A_warm_doc = "Pa^-3 / s; Paterson-Budd A_warm, see [\\ref PatersonBudd]";

    pism_config:Paterson-Budd_Q_cold = 6.0e4;
    pism_config:Paterson-Budd_Q_cold_doc = "J/mol; Paterson-Budd Q_cold, see [\\ref PatersonBudd]";

    pism_config:Paterson-Budd_Q_warm = 13.9e4;
    pism_config:Paterson-Budd_Q_warm_doc = "J/mol; Paterson-Budd Q_warm, see [\\ref PatersonBudd]";

    pism_config:Paterson-Budd_critical_temperature = 263.15;
    pism_config:Paterson-Budd_critical_temperature_doc = "Kelvin; Paterson-Budd critical temperature, see [\\ref PatersonBudd]";

    pism_config:verification_mode = "no";
    pism_config:verification_mode_doc = "; shows whether PISM is running in the verification mode";

    pism_config:enthalpy_cold_bulge_max = 60270.0;
    pism_config:enthalpy_cold_bulge_max_doc = "J kg-1; = (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";
                              
    pism_config:enthalpy_temperate_conductivity_ratio = 0.1;
    pism_config:enthalpy_temperate_conductivity_ratio_doc = "pure number; K in cold ice is multiplied by this fraction to give K0 in [\\ref AschwandenBuelerKhroulevBlatter]";
                              
    pism_config:gpbld_water_frac_coeff = 181.25;
    pism_config:gpbld_water_frac_coeff_doc = "; coefficient in Glen-Paterson-Budd flow law for extra dependence of softness on liquid water fraction (omega) [\\ref GreveBlatter2009, \\ref LliboutryDuval1985]";

    pism_config:gpbld_water_frac_observed_limit = 0.01;
    pism_config:gpbld_water_frac_observed_limit_doc = "; maximum value of liquid water fraction omega for which softness values are parameterized by [\\ref LliboutryDuval1985]; used in Glen-Paterson-Budd-Lliboutry-Duval flow law; compare [\\ref AschwandenBuelerKhroulevBlatter]";

    pism_config:drainage_target_water_frac = 0.01;
    pism_config:drainage_target_water_frac_doc = "; liquid water fraction (omega) above which drainage occurs, but below which there is no drainage; see [\\ref AschwandenBuelerKhroulevBlatter]";

    pism_config:drainage_max_rate = 1.58443823077064e-09;
    pism_config:drainage_max_rate_doc = "s-1; = 0.05 a-1; maximum rate at which liquid water fraction in temperate ice could possibly drain; see [\\ref AschwandenBuelerKhroulevBlatter]";

    pism_config:fresh_water_density = 1000.0;
    pism_config:fresh_water_density_doc = "kg m-3;";
   
    pism_config:sea_water_density = 1028.0;
    pism_config:sea_water_density_doc = "kg m-3;";

    pism_config:bedrock_thermal_density = 3300.0;
    pism_config:bedrock_thermal_density_doc = "kg m-3; for bedrock used in thermal model";

    pism_config:bedrock_thermal_conductivity = 3.0;
    pism_config:bedrock_thermal_conductivity_doc = "J m-1 K-1 s-1; = W m-1 K-1; for bedrock used in thermal model [\\ref RitzEISMINT]";

    pism_config:bedrock_thermal_specific_heat_capacity = 1000.0;
    pism_config:bedrock_thermal_specific_heat_capacity_doc = "J kg-1 K-1; for bedrock used in thermal model [\\ref RitzEISMINT]";

    // for following, reference Lingle & Clark (1985) and  Bueler, Lingle, & Kallen-Brown (2006)
    //    D = E T^3/(12 (1-nu^2)) for Young's modulus E = 6.6e10 N/m^2, lithosphere thickness
    //    T = 88 km, and Poisson's ratio nu = 0.5
    pism_config:lithosphere_density = 3300.0;
    pism_config:lithosphere_density_doc = "kg m-3; lithosphere density used by the bed deformation model. See [\\ref LingleClark, \\ref BLKfastearth]";

    pism_config:lithosphere_flexural_rigidity = 5.0e24;
    pism_config:lithosphere_flexural_rigidity_doc = "N m; lithosphere flexural rigidity used by the bed deformation model. See [\\ref LingleClark, \\ref BLKfastearth]";

    pism_config:mantle_viscosity = 1.0e21;
    pism_config:mantle_viscosity_doc = "Pa s; half-space (mantle) viscosity used by the bed deformation model. See [\\ref LingleClark, \\ref BLKfastearth]";

    pism_config:seconds_per_year = 3.15569259747e7;
    pism_config:seconds_per_year_doc = "; should match the one used by UDUNITS (see src/udunits/pismudunits.dat).";

    pism_config:standard_gravity = 9.81;
    pism_config:standard_gravity_doc = "m s-2; acceleration due to gravity on Earth geoid";

    pism_config:ideal_gas_constant = 8.31441;
    pism_config:ideal_gas_constant_doc = "J mol-1 K-1; ideal gas constant";

    pism_config:climate_forcing_buffer_size = 60;
    pism_config:climate_forcing_buffer_size_doc = "; number of 2D climate forcing records to keep in memory; = 5 years of monthly records";
    
    pism_config:summary_volarea_scale_factor_log10 = 6;
    pism_config:summary_volarea_scale_factor_log10_doc = "; an integer; log base 10 of scale factor to use for volume and area in summary line to stdout";
    
    pism_config:viewer_size = 320;
    pism_config:viewer_size_doc = "; default diagnostic viewer size";

    pism_config:slice_level = 0.0;
    pism_config:slice_level_doc = "meters; level (in meters above the base of ice) used in slice viewers";

// Strings:

   pism_config:run_title = "";
   pism_config:run_title_doc = "Free-form string containing a concise description of the current run. This string is written to output files as the 'title' global attribute.";

   pism_config:institution = "";
   pism_config:institution_doc = "Institution name. This string is written to output files as the 'institution' global attribute.";

   pism_config:reference_date = "1-1-1";
   pism_config:reference_date_doc = "year-month-day; reference date used in PISM output files";

   pism_config:surface_gradient_method = "haseloff";
   pism_config:surface_gradient_method_doc = "method used for surface gradient calculation at staggered grid points; possible values are 'mahaffy', 'eta', 'haseloff' (lowercase)";

   pism_config:grid_periodicity = "none";
   pism_config:grid_periodicity_doc = "PISM grid periodicity; possible values are 'none', 'x', 'y', 'xy' (lowercase).";

   pism_config:grid_ice_vertical_spacing = "quadratic";
   pism_config:grid_ice_vertical_spacing_doc = "; Default vertical spacing in the ice. Possible values: 'quadratic' and 'equal'.";

   pism_config:grid_bed_vertical_spacing = "quadratic";
   pism_config:grid_bed_vertical_spacing_doc = "; Default vertical spacing in the bedrock thermal layer. Possible values: 'quadratic' and 'equal'.";

   pism_config:grid_Mx = 61;
   pism_config:grid_Mx_doc = "; Number of grid points in the x direction.";

   pism_config:grid_My = 61;
   pism_config:grid_My_doc = "; Number of grid points in the y direction.";

   pism_config:grid_Mz = 31;
   pism_config:grid_Mz_doc = "; Number of vertical grid levels in the ice.";

   pism_config:grid_Mbz = 1;
   pism_config:grid_Mbz_doc = "; Number of thermal bedrock layers; 1 level corresponds to no bedrock.";

   pism_config:grid_Lx = 1500e3;
   pism_config:grid_Lx_doc = "m; Default computational box is 3000 km x 3000 km (= 2 Lx x 2 Ly) in horizontal.";

   pism_config:grid_Ly = 1500e3; 
   pism_config:grid_Ly_doc = "m; Default computational box is 3000 km x 3000 km (= 2 Lx x 2 Ly) in horizontal.";

   pism_config:grid_Lz = 4000;
   pism_config:grid_Lz_doc = "meters; Height of the computational domain.";

   pism_config:grid_Lbz = 0;
   pism_config:grid_Lbz_doc = "meters; Thickness of the thermal bedrock layer.";

   pism_config:grid_lambda = 4.0;
   pism_config:grid_lambda_doc = "; Vertical grid spacing parameter. Roughly equal to the factor by which the grid is coarser at an end away from the ice-bedrock interface.";

   pism_config:cold_mode_is_temperate_ice_tolerance = 0.001;
   pism_config:cold_mode_is_temperate_ice_tolerance_doc = "Kelvin; Tolerance within which ice is treated as temperate (cold-ice mode only).";

   pism_config:correct_cell_areas = "yes";
   pism_config:correct_cell_areas_doc = "Compute corrected cell areas using WGS84 datum (for ice area and volume computations).";

   pism_config:WGS84_semimajor_axis = 6378137.0;
   pism_config:WGS84_semimajor_axis_doc = "m; WGS84 reference ellipsoid semi-major axis";

   pism_config:WGS84_semiminor_axis = 6356752.314245;
   pism_config:WGS84_semiminor_axis_doc = "m; WGS84 reference ellipsoid semi-minor axis";

   pism_config:output_medium = "acab artm cbar cbase csurf cflx dHdt diffusivity mask schoofs_theta tauc taud thksmooth topgsmooth usurf wvelsurf temp enthalpy IcebergMask edot_1 edot_2";
   pism_config:output_medium_doc = "Space-separated list of variables to write to the output (in addition to model_state variables) if 'medium' output size is selected. Does not include fields written by boundary models.";

   pism_config:output_big = "acab age artm bfrict bheatflx bmelt bwat bwp cbar cbase cell_area cflx csurf dbdt dHdt dhdt diffusivity enthalpy enthalpybase enthalpysurf hardav lat liqfrac litho_temp lon mask ocean_kill_mask rank schoofs_theta tauc taud_mag temp tempbase tempsurf temp_pa temppabase tempicethk tempicethk_basal thk thksmooth tillphi topg topgsmooth velbase velsurf velbar usurf uvel vvel wvel wvel_rel wvelbase wvelsurf new_mask";
   pism_config:output_big_doc = "Space-separated list of variables to write to the output (in addition to model_state variables) if 'big' output size is selected. Does not include fields written by boundary models.";

   pism_config:ts_bad_set_warning = "WARNING: PISM will sample this quantity at user-specified times.  Fast (e.g. subannual) variability in any coupler-generated fluxes may make these sampled values unusable.";
   pism_config:ts_bad_set_warning_doc = "warning added to metadata for time-derivative-type time series outputs";

   pism_config:ts_bad_set_variables = "divoldt dimassdt surface_ice_flux basal_ice_flux sub_shelf_ice_flux nonneg_rule_flux ocean_kill_flux float_kill_flux";
   pism_config:ts_bad_set_variables_doc = "Space-separated list of scalar diagnostic quantities which are generated by instantaneous time derivatives of PISM quantities.  ts_bad_set_warning is added to metadata for these.  They are not written by default.";

   pism_config:ts_default_variables = "dt ivol ivolcoldf ivoltempf imass iarea iareacoldf iareatempf iareag iareaf ienthalpy";
   pism_config:ts_default_variables_doc = "Space-separated list of scalar diagnostic quantities to save, by default, if -ts_file and -ts_times are used, AND a -ts_vars list is not given.";

   pism_config:backup_interval = 1.0;
   pism_config:backup_interval_doc = "hours; wall-clock time between automatic backups";
}