Full pathname of initial conditions file. If blank CLM will startup from arbitrary initial conditions. If set to .true., interpinic will be called to interpolate the file given by finidat, creating the output file specified by finidat_interp_dest. This requires that finidat be non-blank. Full pathname of master restart file for a branch run. (only used if RUN_TYPE=branch) (Set with RUN_REFCASE and RUN_REFDATE) Component name to use in history and restart files Full pathname of land fraction data file. Clumps per processor. Atmospheric CO2 molar ratio (by volume) only used when co2_type==constant (umol/mol) (Set by CCSM_CO2_PPMV) Type of CO2 feedback. constant = use the input co2_ppmv value prognostic = use the prognostic value sent from the atmosphere diagnostic = use the diagnostic value sent from the atmosphere Supplemental Nitrogen mode and for what type of vegetation it's turned on for. In this mode Nitrogen is unlimited rather than prognosed and in general vegetation is over-productive. NONE = No vegetation types get supplemental Nitrogen ALL = Supplemental Nitrogen is active for all vegetation types If TRUE, separate the vegetated landunit into a crop landunit and a natural vegetation landunit If TRUE, run all urban landunits everywhere where we have valid urban data. This forces memory to be allocated and calculations to be run even for 0-weight urban points. This has a substantial impact on memory use and performance, and should only be used if you're interested in potential urban behavior globally. If TRUE, make ALL pfts, columns and landunits active, even those with 0 weight. This means that computations will be run even over these 0-weight points. THIS IS ONLY FOR TESTING PURPOSES - IT HAS NOT BEEN CHECKED FOR SCIENTIFIC VALIDITY. If TRUE (which is the default), send the expcrt state for the nuopc driver to the ATM even if running with a data ATM If TRUE, square the organic fraction when it's used (as was done in CLM4.5) Otherwise use the fraction straight up (the default for CLM5.0) 10SL_3.5m = standard CLM4 and CLM4.5 version 23SL_3.5m = more vertical layers for permafrost simulations 49SL_10m = 49 layer soil column, 10m of soil, 5 bedrock layers 20SL_8.5m = 20 layer soil column, 8m of soil, 5 bedrock layers 4SL_2m = 4 layer soil column, 2m of soil, 0 bedrock layers User-defined vector of dzsoi. The length of this vector determines nlevgrnd. When the user sets this vector, they have to set soil_layerstruct_userdefined_nlevsoi in the namelist, too; soil_layerstruct_userdefined_nlevsoi must be less than nlevgrnd in this version of the model, even though ideally soil_layerstruct_userdefined_nlevsoi could also equal nlevgrnd. Default: rundef User-defined number of soil layers required to be set in the namelist when the user sets soil_layerstruct_userdefined in the namelist. Default: iundef If TRUE, use variable soil depth. If present on surface dataset, use depth to bedrock information to specify spatially variable soil thickness. If not present, use bottom of soil column (nlevsoi). number of wavelength bands used in SNICAR snow albedo calculation (snicar_numrad_snw=5 is the only supported option; others are EXPERIMENTAL, UNSUPPORTED, and UNTESTED!) type of downward solar radiation spectrum for SNICAR snow albedo calculation (snicar_solarspec='mid_latitude_winter' is the only supported option; others are EXPERIMENTAL, UNSUPPORTED, and UNTESTED!) dust optics type for SNICAR snow albedo calculation (snicar_dust_optics='sahara' is the only supported option; others are EXPERIMENTAL, UNSUPPORTED, and UNTESTED!) snow grain shape used in SNICAR snow albedo calculation (snicar_snw_shape='hexagonal_plate' is supported in ctsm5.1 and 'sphere' in older model versions; others are EXPERIMENTAL, UNSUPPORTED, and UNTESTED!) Toggle to turn on/off aerosol deposition flux in snow in SNICAR (snicar_use_aerosol='.false.' is EXPERIMENTAL, UNSUPPORTED, and UNTESTED!) option to activate BC-snow internal mixing in SNICAR snow albedo calculation (snicar_snobc_intmix='.true.' is EXPERIMENTAL, UNSUPPORTED, and UNTESTED!) option to activate dust-snow internal mixing in SNICAR snow albedo calculation (snicar_snodst_intmix='.true.' is EXPERIMENTAL, UNSUPPORTED, and UNTESTED!) option to activate organic carbon (OC) in SNICAR snow albedo calculation (do_sno_oc='.true.' is EXPERIMENTAL, UNSUPPORTED, and UNTESTED!) Index of rooting profile for water Changes rooting profile from Zeng 2001 double exponential (0) to Jackson 1996 single exponential (1) to Koven uniform exponential (2). Index of rooting profile for carbon Changes rooting profile from Zeng 2001 double exponential (0) to Jackson 1996 single exponential (1) to Koven uniform exponential (2). Index of rooting profile for soil carbon Changes rooting profile from Zeng 2001 double exponential (0) to Jackson 1996 single exponential (1) to Koven uniform exponential (2). Variant index of rooting profile for water (Currently only used for Jackson 1996 method) Variant index of rooting profile for carbon and soil carbon (Currently only used for Jackson 1996 method) Index of rooting profile for carbon Changes rooting profile from Zeng 2001 double exponential (0) to Jackson 1996 single exponential (1) to Koven uniform exponential (2). Index of evaporative resistance method. Changes soil evaporative resistance method from Sakaguchi and Zeng 2009 Beta function (0) to Swenson and Lawrence 2014 dry surface layer formulation (1). The method type to use for CNFire nofire: Turn fire effects off li2014qianfrc: Reference paper Li, et. al.(2014) tuned with QIAN atmospheric forcing li2016crufrc: Reference paper Li, et. al.(2016) tuned with CRU-NCEP atmospheric forcing li2021gswpfrc: Reference paper Li, et. al.(2021?) tuned with GSWP3 atmospheric forcing Potential human ignition counts (/person/month) boreal peat fires (/hr) non-boreal peat fires (/hr) Scalar for cropfire (/hr) Critical RH for ignition (0-100) Saturation RH for ignition (0-100) Lower threshold for fuel mass needed for ignition Upper threshold for fuel mass needed for ignition Saturation BTRAN for ignition (0-1) Critical BTRAN for ignition (0-1) Global constant for deforestation fires (/day) Fire occurance for high GDP areas that are tree dominated (fraction) Combustion completeness factor for litter (unitless) Combustion completeness factor for CWD[Course Woody Debris] (unitless) Critical threshold for truncation of Nitrogen (truncate Nitrogen states to zero below this value) Critical threshold for truncation of Carbon (truncate Carbon states to zero below this value) Critical threshold of negative Nitrogen to die (abort when Nitrogen states are below this value) Critical threshold of negative Carbon to die (abort when Carbon states are below this value) Slope of free living Nitrogen fixation with annual ET Intercept of free living Nitrogen fixation with zero annual ET If TRUE use the undercanopy stability term used with CLM4.5 (Sakaguchi&Zeng, 2008) If TRUE, include biomass heat storage in canopy energy balance. Max number of iterations used in subr. CanopyFluxes. For many years, 40 was the hardwired default value. Default: 40 Fraction of intercepted precipitation If TRUE use clm5 equation for fraction of intercepted precipitation Maximum fraction of leaf that may be wet prior to drip occuring Scalar multiplier for base flow rate (ONLY used if lower_boundary_condition is not aquifer or table) Index of solution method of Richards equation. Change method for richards equation solution and boundary conditions. CLM 4.5 - soilwater_movement_method = 0 (Zeng and Decker, 2009, method). CLM 5.0 - soilwater_movement_method = 1 (adaptive time stepping moisture form from Martyn Clark). 1 (adaptive time stepping moisture form Index of upper boundary condition for Richards equation. Index of lower boundary condition for Richards equation. lower_boundary_condition = 1 : flux lower boundary condition (use with soilwater_movement_method=adaptive time stepping) lower_boundary_condition = 2 : zero-flux lower boundary condition (use with soilwater_movement_method=adaptive time stepping) lower_boundary_condition = 3 : water table head-based lower boundary condition w/ aquifer layer. (use with soilwater_movement_method=adaptive time stepping) lower_boundary_condition = 4 : 11-layer solution w/ aquifer layer (only used with soilwater_movement_method=Zeng&Decker 2009) TODO(bja, 2015-09) these should be strings so they have meaningful names instead of ints. minimum time step length (seconds) for adaptive time stepping in richards equation a very small number: used to check for sub step completion for adaptive time stepping in richards equation tolerance to halve length of substep for adaptive time stepping in richards equation tolerance to double length of substep for adaptive time stepping in richards equation Minimum leaf area index for irrigation to occur Time of day to check whether we need irrigation, seconds (0 = midnight). We start applying the irrigation in the time step FOLLOWING this time. Desired amount of time to irrigate per day (sec). Actual time may differ if this is not a multiple of dtime. Target soil matric potential for irrigation (mm). When we irrigate, we aim to bring the total soil moisture in the top (irrig_depth) m of soil up to this level. Soil depth to which we measure for irrigation (m) Determines soil moisture threshold at which we irrigate. If h2osoi_liq_wilting_point is the soil moisture level at wilting point and h2osoi_liq_target is the soil moisture level at the target irrigation level (given by irrig_target_smp), then the threshold at which we irrigate is h2osoi_liq_wilting_point + irrig_threshold_fraction*(h2osoi_liq_target - h2osoi_liq_wilting_point) A value of 1 means that we irrigate whenever soil moisture falls below the target. A value of 0 means that we only irrigate when soil moisture falls below the wilting point. Threshold for river water volume below which irrigation is shut off (as a fraction of available river water), if limit_irrigation_if_rof_enabled is .true. A threshold of 0 means allow all river water to be used; a threshold of 0.1 means allow 90% of the river volume to be used; etc. If TRUE, limit irrigation when river storage drops below a threshold. Only applies if using an active runoff (ROF) model; otherwise, river storage-based limitation is turned off regardless of the setting of this namelist variable. If TRUE, supply irrigation from groundwater (in addition to surface water). Can only be set if limit_irrigation_if_rof_enabled is true (otherwise groundwater extraction is never invoked). Cannot be combined with lower_boundary_condition = 3 or 4 Irrigation method used if not specified on surface dataset If TRUE, irrigation will be active. If TRUE, fsat will be set to zero for crop columns. Number of multiple elevation classes over glacier points. If TRUE, dynamically change areas and topographic heights over glacier points. Only works when running with a non-stub glacier model. Behavior of each glacier region (GLACIER_REGION in surface dataset). First item corresponds to GLACIER_REGION with ID 0 in the surface dataset, second to GLACIER_REGION with ID 1, etc. Allowed values are: 'multiple': grid cells can potentially have multiple glacier elevation classes, but no virtual columns 'virtual': grid cells have virtual columns: values are computed for every glacier elevation class, even those with 0 area (in order to provide surface mass balance for every glacier elevation class). 'single_at_atm_topo': glacier landunits in these grid cells have a single column, whose elevation matches the atmosphere's topographic height (so that there is no adjustment due to downscaling) Behavior of 'virtual' is required in the region where we have an ice sheet model Treatment of ice melt for each glacier region (GLACIER_REGION in surface dataset). First item corresponds to GLACIER_REGION with ID 0 in the surface dataset, second to GLACIER_REGION with ID 1, etc. Allowed values are: 'replaced_by_ice': any melted ice runs off and is immediately replaced by solid ice; this results in positive liquid runoff and negative ice runoff 'remains_in_place': any melted ice remains in place as liquid until it refreezes; thus, ice melt does not result in any runoff IMPORTANT NOTE: Regions with the 'remains_in_place' behavior also do not compute SMB (because negative SMB would be pretty much meaningless in those regions). Thus, you cannot use this behavior where GLC is operating. Regions with the 'replaced_by_ice' behavior also compute SMB for the vegetated column. Treatment of ice runoff for each glacier region (GLACIER_REGION in surface dataset). First item corresponds to GLACIER_REGION with ID 0 in the surface dataset, second to GLACIER_REGION with ID 1, etc. Allowed values are: 'remains_ice': ice runoff is sent to the river model as ice; this is a crude parameterization of iceberg calving, and so is appropriate in regions where there is substantial iceberg calving in reality 'melted': ice runoff generated by the CLM physics (primarily due to snow capping) is melted (generating a negative sensible heat flux) and runs off as liquid; this is appropriate in regions that have little iceberg calving in reality. This can be important to avoid unrealistic cooling of the ocean and consequent runaway sea ice growth. Only applies when melt_non_icesheet_ice_runoff is .true. Number of days before one considers the perennially snow-covered point 'land ice' (and thus capable of generating a positive surface mass balance for the glacier model). This is meant to compensate for the fact that, with small values of h2osno_max, the onset of a snow-capped state (and thus conversion to land ice) can occur in an unrealistically short amount of time. Thus, in general, large values of h2osno_max should have glc_snow_persistence_max_days = 0; small values of h2osno_max should have glc_snow_persistence_max_days > 0. Visible and Near-infrared albedo's for glacier ice CN Maintenence Respiration base rate for roots (if NOT set, use the value for br_mr on the params file) Switch to turn on root and stem respiratory acclimation Atkin, Fisher et al. (2008) and Lombardozzi et al. (2015) Switch to inihibit photosynthesis in daytime Lloyd et al. 2010, & Metcalfe et al. 2012 Modify photosynthesis and leaf maintence respiration for crop Leaf maintencence respiration for canopy top at 25C method to use 0 Scaled by vcmax25top 1 Ryan 1991 2 Atkin 2015 Stomatal conductance model method to use Ball-Berry1987 --- Ball Berry 1987 methodology Medlyn2011 ------- Medlyn 2011 methodology Scalar of leaf respiration to vcmax The maximum value to use for zeta under stable conditions baseline proportion of nitrogen allocated for electron transport (J) Toggle to turn on the FATES model Functionally Assembled Terrestrial Ecosystem Simulator (FATES) Switch deciding which nutrient model to use in FATES. (Only relevant if FATES is on) Switch defining the cadence at which seeds are dispersed across gridcells. Setting the switch value to zero turns off dispersal. Setting the switch to 1, 2, or 3 sets the dispersal cadence to daily, monthly or yearly. The daily cadence is primarily recommended for test and debug only. Note that turning this feature on will result in more memory usage. (Only relevant if FATES is on) Toggle to turn on the tree damage module in FATES (Only relevant if FATES is on) Turn on spitfire module to simulate fire by setting fates_spitfire_mode > 0. Allowed values are: 0 : Simulations of fire are off 1 : use a global constant lightning rate found in fates_params. 2 : use an external lightning dataset. 3 : use an external confirmed ignitions dataset (not available through standard CSEM dataset collection). 4 : use external lightning and population datasets to simulate both natural and anthropogenic 5 : use gross domestic production and population datasets to simulate anthropogenic fire supression ignitions. (Only relevant if FATES is on) Toggle to turn on fixed biogeography mode (Only relevant if FATES is on) Toggle to turn on no competition mode (only relevant if FATES is being used). Toggle to turn on FATES satellite phenology mode (only relevant if FATES is being used). Toggle to turn on the logging module (Only relevant if FATES is on) Toggle to turn on plant hydraulics (Only relevant if FATES is on) Toggle to turn on cohort age tracking (by default FATES only tracks age of patches) (Only relevant if FATES is on). Toggle to turn on Static Stand Structure Mode (only relevant if FATES is being used). (Only relevant if FATES is on). Toggle to turn on prescribed physiology (Only relevant if FATES is on). Toggle to turn on inventory initialization to startup FATES (Only relevant if FATES is on). Full pathname to the inventory initialization control file. (Required, if use_fates_inventory_init=T) (Only relevant if FATES is on). Setting for what types of FATES history to be allocate and calculated at the dynamics timestep (1st integer) and the model timestep (2nd integer). This must be consistent with hist_fincl*, ie output variables must not be listed if the output level is not enabled. 0 = no fates history variables are calculated or allocated 1 = only time x space (3d) fates history variables allowed 2 = multiplexed dimensioned fates history is also allowed (Only relevant if FATES is on) If TRUE, enable use of land use harmonization (LUH) state and transition data from luh_timeseries file. (Also, only valid for use_fates = true and is incompatible with transient runs currently.) Full pathname of unified land use harmonization (LUH) data file. This causes the land-use types to vary over time. (Required, if use_fates_luh=T) (Only relevant if FATES is on). Toggle to turn on the LUNA model, to effect Photosynthesis by leaf Nitrogen LUNA operates on C3 and non-crop vegetation (see vcmax_opt for how other veg is handled) LUNA: Leaf Utilization of Nitrogen for Assimilation Toggle to turn on the hillslope model Toggle to turn on meteorological downscaling in hillslope model Toggle to turn on surface water routing in the hillslope hydrology model Method for calculating hillslope saturated head gradient Method for calculating transmissivity of hillslope columns Method for distributing pfts across hillslope columns Method for distributing soil thickness across hillslope columns Toggle to turn on the plant hydraulic stress model How LUNA and Photosynthesis (if needed) will get Leaf nitrogen content lnc_opt = true get from leaf N from CN model lnc_opt = false get based on LAI and fixed CN ratio from parameter file Full pathname datafile with plant function type (PFT) constants combined with constants for biogeochem modules Full pathname datafile with fates parameters (Only relevant if FATES is on). Full pathname of surface data file. SNICAR (SNow, ICe, and Aerosol Radiative model) optical data file name SNICAR (SNow, ICe, and Aerosol Radiative model) snow aging data file name If TRUE, write list of all output fields to separate file for documentation purposes Per file averaging flag. 'A' (average over history period) 'I' (instantaneous) 'X' (maximum over history period) 'M' (minimum over history period) 'LXXXXX' (local solar time at XXXXX seconds of day) Averaging type of output for 1D vector output (when hist_dov2xy is false). GRID means average all land-units up to the grid-point level LAND means average all columns up to the land-unit level COLS means average all PFT's up to the column level PFTS means report everything on native PFT level If TRUE, implies output data on a 2D latitude/longitude grid. False means output in 1D vector format. One setting per history tape series. If TRUE, indicates do NOT output any default history fields (requires you to use hist_fincl* to set the exact output fields to use).. Fields to exclude from history tape series 1. Fields to exclude from history tape series 2. Fields to exclude from history tape series 3. Fields to exclude from history tape series 4. Fields to exclude from history tape series 5. Fields to exclude from history tape series 6. Fields to exclude from history tape series 7. Fields to exclude from history tape series 8. Fields to exclude from history tape series 9. Fields to exclude from history tape series 10. Fields to add to history tape series 1. Fields to add to history tape series 2. Fields to add to history tape series 3. Fields to add to history tape series 4. Fields to add to history tape series 5. Fields to add to history tape series 6. Fields to add to history tape series 7. Fields to add to history tape series 8. Fields to add to history tape series 9. Fields to add to history tape series 10. Per tape series maximum number of time samples. Per tape series history file density (i.e. output precision) 1=double precision 2=single precision Default: 2,2,2,2,2,2,2,2,2,2 Per tape series history write frequency. positive means in time steps 0=monthly negative means hours (i.e. 5 means every 24 time-steps and -24 means every day Default: 0,-24,-24,-24,-24,-24,-24,-24,-24,-24 number of segments per clump for decomposition Default: 20 Perturbation limit when doing error growth test If FALSE, don't write any restart files. Turn urban air conditioning/heating ON or OFF and add wasteheat: OFF = Air conditioning/heating is OFF in buildings, internal temperature allowed to float freely ON = Air conditioning/heating is ON in buildings, internal temperature constrained ON_WASTEHEAT = Air conditioning/heating is ON and waste-heat sent to urban canyon If TRUE, urban traffic flux will be activated (Currently NOT implemented). 0 = simpler method (clm4_5) 1 = prognostic calculation of interior building temp (clm5_0) Human heat stress indices: ALL = All indices will be calculated FAST = A subset of indices will be calculated (will not include the computationally expensive wet bulb calculation and associated indices) NONE = No indices will be calculated Whether to use subgrid fluxes for snow Whether snow on the vegetation canopy affects the radiation/albedo calculations Whether to run some tests of ncdio_pio as part of the model run. This is typically only used in automated tests. If true, allocate memory for and use a second crop grain pool. This is meant only for software testing of infrastructure to support the AgSys crop model integration. This option can be dropped once AgSys is integrated and we have tests of it. If true, allocate memory for two crop reproductive structure pools and send all reproductive C and N to the second reproductive structure pool instead of the grain pool. This is meant only for software testing of infrastructure to support the AgSys crop model integration. This option can be dropped once AgSys is integrated and we have tests of it. If true, do NOT use grain C/N to replenish the crop seed deficits. This is needed when doing software testing to verify that we can get bit-for-bit identical answers when using a reproductive structure pool as when using a grain pool (in conjunction with for_testing_use_repr_structure_pool). We do this testing to have some tests of the infrastructure to support the AgSys crop model integration. This option can be dropped if/when we stop doing this software testing, e.g., because we have integrated AgSys and have tests of it that make these software infrastructure tests obsolete. Turn on methane model. Standard part of CLM45BGC model. CLM Biogeochemistry mode : Carbon Nitrogen model (CN) (or CLM45BGC if phys=clm4_5, vsoilc_centbgc='on', and clm4me='on') CLM Biogeochemistry mode : Carbon Nitrogen with Dynamic Global Vegetation Model (CNDV) (or CLM45BGCDV if phys=clm4_5, vsoilc_centbgc='on', and clm4me='on') Turn the Fixation and Uptate of Nitrogen model version 2 (FUN2.0) Requires the CN model to work (either CN or CNDV). Nitrification/denitrification splits the prognostic mineral N pool into two mineral N pools: NO3 and NH4, and includes the transformations between them. Turned on for BGC FATES currently allows it to be true or false, but will be hardwired to true later Multiplier for heterotrophic respiration for max denitrification rates Exponent power for heterotrophic respiration for max denitrification rates Maximum nitrification rate constant (1/s) Toggle to use 25 lake layers instead of 10 (extralaklayers=".true." is EXPERIMENTAL, UNSUPPORTED, and UNTESTED!) Toggle to turn on the VIC hydrologic parameterizations (vichydro=".true." is EXPERIMENTAL, UNSUPPORTED!) Toggle to turn on the prognostic crop model Toggle to turn on the prognostic fertilizer for crop model Toggle to turn on the 1-year grain product pool in the crop model Fraction of post-harvest crop residues (leaf and stem) to move to 1-year product pool instead of letting them fall as litter. Default: 0.0 Type of mapping to use for base temperature for prognostic crop model constant = Just use baset from the PFT parameter file varytropicsbylat = Vary the tropics by latitude Only used when baset_mapping == varytropicsbylat Slope with latitude in degrees to vary tropical baset by Only used when baset_mapping == varytropicsbylat Intercept at zero latitude to add to baset from the PFT parameter file Initial seed Carbon to use at planting (only used when CN is on as well as crop) Parameter to set the type of ozone vegetation stress method unset = (default) ozone stress vegetation method is off stress_lombardozzi2015 = ozone stress vegetation functions from Danica Lombardozzi 2015 stress_falk = ozone stress vegetation functions from Stefanie Falk (issue #1224) Default: "unset" Phenology onset depends on the vegetation type (only used when CN is on) Set to .true. in order to override crop harvesting logic and to instead harvest the day before the next sowing date. Used to generate growing-degree day outputs that can be used with an external script to generate new GDD requirement ("cultivar") files. Set to .false. in order to ignore crop PFT parameter for maximum growing season length (mxmat). Must be set to .false. when generate_crop_gdds is .true. Method for determining what the minimum critical day length for seasonal decidious leaf offset depends on Constant ----------- constant value of crit_dayl from parameter file (value from White 2001) DependsOnLat ------- Higher values at high latitudes down to value from parameter file for temperate and equatorial regions (L. Birch et. al, GMD 2021) DependsOnVeg ------- Arctic vegetation with higher value and temperate vegetation with crit_dayl from parameter file DependsOnLatAndVeg - Arctic vegetation depends on latitude as above, but temperate vegetation fixed at crit_dayl value from parameter file (only used when CN is on) Toggle to turn on calculation of SNow and Ice Aerosol Radiation model (SNICAR) albedo forcing diagnostics for each aerosol species Toggle to turn all history output completely OFF (possibly used for testing) Toggle for vancouver specific logic. Toggle for mexico city specific logic. If true, any ocean (i.e., wetland) points on the surface dataset are converted to bare ground (or whatever vegetation is given in that grid cell - but typically this will be bare ground due to lack of vegetation in grid cells with 100% ocean). Number of dominant pfts, so this determines the number of active pfts. Selecting the value 0 means DO NOTHING, ie all pfts in the input data are active. Default: 0 Number of dominant landunits, so this determines the number of active landunits. Selecting the value 0 means DO NOTHING, ie all landunits in the input data are active. Default: 0 If true, this directs the model to collapse the urban landunits to the dominant urban landunit. Selecting .false. means DO NOTHING, ie all urban landunits found in the input data are active. Default: .false. Percentage threshold above which the model keeps the soil landunit. Selecting the value 0 means DO NOTHING. Default: 0 Percentage threshold above which the model keeps the crop landunit. Selecting the value 0 means DO NOTHING. Default: 0 Percentage threshold above which the model keeps the glacier landunit. Selecting the value 0 means DO NOTHING. Default: 0 Percentage threshold above which the model keeps the lake landunit. Selecting the value 0 means DO NOTHING. Default: 0 Percentage threshold above which the model keeps the wetland landunit. Selecting the value 0 means DO NOTHING. Default: 0 Percentage threshold above which the model keeps the urban landunits. Selecting the value 0 means DO NOTHING. If collapse_urban = .false., the same threshold will apply to all three urban landunits if they are present. If collapse_urban = .true., this threshold will apply to the single collapsed urban landunit if presnet. Default: 0 Toggle to turn on the dynamic root model Toggle to turn on on diagnostic Snow Radiative Effect Orography file with surface heights and land area fraction CLM grid file CESM domain file CAM file Raw topography file CAM topography file Number of longitudes to use for a regional grid (for single-point set to 1) Number of latitudes to use for a regional grid (for single-point set to 1) Northern edge of the regional grid Southern edge of the regional grid Eastern edge of the regional grid Western edge of the regional grid Historical greenhouse gas concentrations from CAM, only used by getco2_historical.ncl Aerosol deposition file name (only used for aerdepregrid.ncl) Full pathname of CLM fraction dataset (only used for mkdatadomain). Full pathname of CLM grid dataset (only used for mkdatadomain). Full pathname of output domain dataset (only used for mkdatadomain). Type of domain file to create (ocean or atmosphere) (only used for mkdatadomain) If TRUE, repartition rain/snow from atmosphere based on temperature. If TRUE, downscale longwave radiation over glacier landunits. This downscaling is conservative. Default: .true. Surface temperature lapse rate (K m-1) A positive value means a decrease in temperature with increasing height Longwave radiation lapse rate (W m-2 m-1) A positive value means a decrease in LW radiation with increasing height Only relevant if glcmec_downscale_longwave is .true. Relative limit for how much longwave downscaling can be done (unitless) The pre-normalized, downscaled longwave is restricted to be in the range [lwrad*(1-longwave_downscaling_limit), lwrad*(1+longwave_downscaling_limit)] This parameter must be in the range [0,1] Only relevant if glcmec_downscale_longwave is .true. Temperature below which all precipitation falls as snow, for glacier columns (deg C) Only relevant if repartition_rain_snow is .true. Temperature above which all precipitation falls as rain, for glacier columns (deg C) Only relevant if repartition_rain_snow is .true. Temperature below which all precipitation falls as snow, for non-glacier columns (deg C) Only relevant if repartition_rain_snow is .true. Temperature above which all precipitation falls as rain, for non-glacier columns (deg C) Only relevant if repartition_rain_snow is .true. If TRUE, ice runoff generated from non-glacier columns and glacier columns outside icesheet regions is converted to liquid, with an appropriate sensible heat flux. That is, the atmosphere (rather than the ocean) melts the ice. (Exception: ice runoff generated to ensure conservation with dynamic landunits remains as ice.) First year to loop over for Nitrogen Deposition data Last year to loop over for Nitrogen Deposition data Simulation year that aligns with stream_year_first_ndep value Filename of input stream data for Nitrogen Deposition Stream meshfile for Nitrogen Deposition data Time interpolation mode to determine how to handle data before and after the times in the file cycle = Always cycle over the data extend = Use the first time before the available data, and use the last time after the available data limit = Only use the data within the times available -- abort if the model tries to go outside it Time interpolation method to use for Nitrogen Deposition Colon delimited list of variables to read from the streams file for nitrogen deposition (Normally just read the single variable NDEP_year or NDEP_month) Mapping method from Nitrogen deposition input file to the model resolution bilinear = bilinear interpolation nn = nearest neighbor nnoni = nearest neighbor on the "i" (longitude) axis nnonj = nearest neighbor on the "j" (latitude) axis spval = set to special value copy = copy using the same indices Which dust emission method is going to be used. Either the Zender 2003 scheme or the Leung 2023 scheme. (NOTE: The Leung 2023 method is NOT currently available) Option only applying for the Zender_2003 method for whether the soil erodibility file is handled here in CTSM, or in the ATM model. (only used when dust_emis_method is Zender_2003) Option only applying for the Zender_2003 method for whether the soil erodibility file is handled here in CTSM, or in the ATM model. (only used when dust_emis_method is Zender_2003) bilinear = bilinear interpolation nn = nearest neighbor nnoni = nearest neighbor on the "i" (longitude) axis nnonj = nearest neighbor on the "j" (latitude) axis spval = set to special value copy = copy using the same indices Filename of input stream data for Zender's soil erodibility source function (only used when dust_emis_method is Zender_2003, and zender_soil_erod_source is lnd) mesh filename of input stream data for Zender's soil erodibility source function (only used when dust_emis_method is Zender_2003, and zender_soil_erod_source is lnd) Filename of input stream data for finundated inversion of observed (from Prigent dataset) to hydrologic variables (either TWS or ZWT) mesh filename of input stream data for finundated inversion of observed (from Prigent dataset) to hydrologic variables (either TWS or ZWT) Toggle to turn on use of input prescribed soil moisture streams rather than have CLM prognose it (EXPERIMENTAL) First year to loop over for prescribed soil moisture streams data Last year to loop over for prescribed soil moisture streams data Simulation year that aligns with stream_year_first_soilm value Filename of input stream data for prescribed soil moisture streams data Time interpolation method to use for prescribed soil moisture streams data Offset in time coordinate for soil moisture streams (sec) If false will abort if using soil moisture streams and find a point where the model shows H2OSOI_VOL should be set because it's vegetated, but the input soilm streams dataset shows that point is missing. If true, will ignore the prescribed soilm data for that point and let the model run for that point without prescribed data. Toggle to turn on use of LAI streams in place of the LAI on the surface dataset when using Satellite Phenology mode. First year to loop over for LAI data Last year to loop over for LAI data Simulation year that aligns with stream_year_first_lai value Filename of input stream data for LAI Filename of input stream data for LAI dtlimit (ratio of max/min stream delta times) for LAI streams, which allows for cycling over a year of data Time interpolation method to use with LAI streams Mapping method from LAI input file to the model resolution bilinear = bilinear interpolation nn = nearest neighbor nnoni = nearest neighbor on the "i" (longitude) axis nnonj = nearest neighbor on the "j" (latitude) axis spval = set to special value copy = copy using the same indices First year to loop over for crop calendar data Last year to loop over for crop calendar data Simulation year that aligns with stream_year_first_cropcal value By default, a value in stream_fldFileName_swindow_start or _end outside the range [1, 365] (or 366 in leap years) will cause the run to fail. Set this to .true. to instead fall back on the paramfile sowing windows. Filename of input stream data for date (day of year) of start of sowing window. Cells with the same sowing window start and end date are always planted on that date, regardless of climatic conditions/history. Filename of input stream data for date (day of year) of end of sowing window. Cells with the same sowing window start and end date are always planted on that date, regardless of climatic conditions/history. Filename of input stream data for cultivar growing degree-day targets Filename of input stream data for crop calendar inputs First year to loop over for Lightning data Last year to loop over for Lightning data Simulation year that aligns with stream_year_first_lightng value Filename of input stream data for Lightning Stream meshfile for Nitrogen Deposition data Time interpolation method to use with Lightning streams Mapping method from Lightning input file to the model resolution bilinear = bilinear interpolation nn = nearest neighbor nnoni = nearest neighbor on the "i" (longitude) axis nnonj = nearest neighbor on the "j" (latitude) axis spval = set to special value copy = copy using the same indices First year to loop over for human population density data Last year to loop over for human population density data Simulation year that aligns with stream_year_first_popdens value Filename of input stream data for human population density mesh file for input stream data for human population density Time interpolation method to use with human population density streams Mapping method from human population density input file to the model resolution bilinear = bilinear interpolation nn = nearest neighbor nnoni = nearest neighbor on the "i" (longitude) axis nnonj = nearest neighbor on the "j" (latitude) axis spval = set to special value copy = copy using the same indices First year to loop over for urban time varying data Last year to loop over for urban time varying data Simulation year that aligns with stream_year_first_urbantv value Filename of input stream data for urban time varying mesh filename of input stream data for urban time varying Time interpolation method to use with urban time varying streams Mapping method from urban time varying input file to the model resolution bilinear = bilinear interpolation nn = nearest neighbor nnoni = nearest neighbor on the "i" (longitude) axis nnonj = nearest neighbor on the "j" (latitude) axis spval = set to special value copy = copy using the same indices datm input directory datm output directory Datm logfile name Mapping file to go from one resolution/land-mask to another resolution/land-mask Land mask description for mksurfdata input files Resolution of finundated inversion streams dataset (stream_fldfilename_ch4finundated) to use for methane model (only applies when CN and methane model are turned on) Resolution of Lightning dataset to use for CN or FATES fire model (only applies when CN or FATES and the fire model is turned on) Check that the resolution and land-mask is valid before continuing. Add a note to the output namelist about the options given to build-namelist CLM run type. 'default' use the default type of clm_start type for this configuration 'cold' is a run from arbitrary initial conditions 'arb_ic' is a run using initial conditions if provided, OR arbitrary initial conditions if no files can be found 'startup' is an initial run with initial conditions provided. 'continue' is a restart run. 'branch' is a restart run in which properties of the output history files may be changed. Shared Socioeconomic Pathway (SSP) and Representative Concentration Pathway (RCP) combination for future scenarios The form is SSPn-m.m Where n is the SSP number and m.m is RCP radiative forcing at peak or 2100 in W/m^2 n is just the whole number of the specific SSP scenario. The lower numbers have higher mitigation - the higher numbers less mitigation, more than one SSP can result in the same RCP forcing hist means do NOT use a future scenario, just use historical data. Land mask description General configuration of model version and atmospheric forcing to tune the model to run under. This sets the model to run with constants and initial conditions that were set to run well under the configuration of model version and atmospheric forcing. To run well constants would need to be changed to run with a different type of atmospheric forcing. (Some options for the newest physics will be based on previous tuning, and buildnml will let you know about this) If 1, turn on the MEGAN model for BVOC's (Biogenic Volitile Organic Compounds) Year to simulate and to provide datasets for (such as surface datasets, initial conditions, aerosol-deposition, Nitrogen deposition rates etc.) A sim_year of 1000 corresponds to data used for testing only, NOT corresponding to any real datasets. A sim_year greater than 2015 corresponds to ssp_rcp scenario data A sim_year of PtVg refers to the Potential Vegetation dataset, that doesn't include human influences Most years are only used for clm_tools and there aren't CLM datasets that correspond to them. CLM datasets exist for years: 1000 (for testing), 1850, and 2000 Range of years to simulate transitory datasets for (such as dynamic: land-use datasets, aerosol-deposition, Nitrogen deposition rates etc.) Constant means simulation will be held at a constant year given in sim_year. A sim_year_range of 1000-1002 or 1000-1004 corresponds to data used for testing only, NOT corresponding to any real datasets. A sim_year_range that goes beyond 2005 corresponds to historical data until 2005 and then scenario data beyond that point. Namelist entries to demand be provided on the namelist. Description of the use case selected. Attributes to use when looking for an initial condition file (finidat) if interpolation is turned on (use_init_interp is .true.) How close in years to use when looking for an initial condition file (finidat) if interpolation is turned on (use_init_interp is .true.) Simulation years you can look for in initial condition files (finidat) if interpolation is turned on (use_init_interp is .true.) Command line argument for setting up your simulation in a mode for faster throughput. By default turns off some options, and sets up for a lower level of output. When bgc_mode is some level of prognostic BGC (so NOT Satellite Phenology) it also sets up for accelerated decomposition. NOTE: THIS CORRESPONDS DIRECTLY TO THE env_run.xml VARIABLE OF THE SAME NAME. Set the env_run variable, rather than setting this directly. Command line arguement for biogeochemistry mode for CLM4.5 sp = Satellitte Phenology cn = Carbon Nitrogen model bgc = CLM4.5 BGC model with: CENTURY model pools Nitrification/De-nitrification Methane model Vertically resolved Carbon fates = FATES Functionally Assembled Terrestrial Ecosystem Simulator (ecosystem demography model with below ground BGC): Flag for overriding the crash that should occur if user tries to start the model from a restart file made with a different version of the soil decomposition structure than is currently being used. Flag for setting the state of the Accelerated decomposition spinup state for the BGC model. 0 = normal model behavior; 1 = AD spinup (standard) 2 = AD spinup (accelerated spinup from Ricciuto, doesn't work for CNDV and not implemented for CN soil decomposition) Entering and exiting spinup mode occurs automatically by comparing the namelist and restart file values for this variable. NOTE: THIS CAN ONLY BE SET TO NON-ZERO WHEN BGC_MODE IS NOT SATELITE PHENOLOGY! Base advective flux (downwards) for SOM. Maximum depth to mix soils to by croturbation, in permafrost soils. If TRUE, reduce heterotrophic respiration according to available oxygen predicted by CH4 submodel. separate q10 for frozen soil respiration rates. default to same as above zero rates If TRUE, add extra diagnostics for methane model to the history files Profile over which to distribute C and N coming from surface pools (leaves, stem, grain). If true, no denitrification or nitrification in frozen soil layers. (EXPERIMENTAL, UNSUPPORTED, and UNTESTED!) Number of days over which to use exponential relaxation of NPP in N fixation calculation Soil decomposition method None -- No soil decomposition is done CENTURYKoven2013 -- CENTURY model in CTSM from Koven et. al. 2013 MIMICSWieder2015 -- MIMICS model in CTSM from Wieder et. al. 2015 An active soil decomposition method requires the BGC or FATES model to work And both BGC and FATES models require an active soil decomposition model Flag to reseed any dead plants on startup from reading the initial conditions file Harvest the XSMR pool at crop harvest time to the atmosphere slowly at an exponential rate Enable C13 model Enable C14 model Flag to use the atmospheric time series of C14 concentrations from bomb fallout and Seuss effect, rather than natural abundance C14 (nominally set as 10^-12 mol C14 / mol C) Filename with time series of atmospheric Delta C14 data. variables in file are "time" and "Delta14co2_in_air". time variable is in format: years since 1850-01-01 0:0:0.0 units are permil. Flag to use the atmospheric time series of C13 concentrations from natural abundance and the Seuss Effect, rather than static values. Filename with time series of atmospheric Delta C13 data, which use CMIP6 format. variables in file are "time" and "delta13co2_in_air". time variable is in format: years since 1850-01-01 0:0:0.0. units are permil. There is a bug that causes incorrect values for C isotopes if running init_interp from a case without C isotopes to a case with C isotopes (https://github.com/ESCOMP/ctsm/issues/67). Normally, an error-check prevents you from doing this interpolation (until we have fixed that bug). However, we sometimes want to bypass this error-check in system tests. This namelist flag bypasses this error-check. If TRUE, weight btran (vegetation soil moisture availability) by unfrozen layers only, assuming that vegetation will allocate roots preferentially to the active layer. (EXPERIMENTAL, UNSUPPORTED, and UNTESTED!) If TRUE, weight btran (vegetation soil moisture availability) by the active layer, as defined by the greatest thaw depth over the current and prior years. (EXPERIMENTAL, UNSUPPORTED, and UNTESTED!) If TRUE use additional stress deciduous onset trigger Apply the guardrail for leaf-Nitrogen that ensures it doesn't go negative or too small Allow the CN ratio to flexibly change with the simulation, rather than being fixed Michaelis Menten nitrogen uptake kinetics How much Carbon to initialize vegetation pools (leafc/frootc and storage) to when -- Michaelis Menten nitrogen uptake kinetics is on Flexible CN ratio used for Phenology (EXPERIMENTAL, UNSUPPORTED, and UNTESTED!) Reduce day length factor (NOT implemented) Vcmax calculation for Photosynthesis vcmax_opt = 4 As for vcmax_opt=0, but using leafN, and exponential if tree (EXPERIMENTAL, UNSUPPORTED, and UNTESTED!) vcmax_opt = 3 Based on leafN and VCAD (used with Luna for crop and C4 vegetation) vcmax_opt = 0 Based on canopy top and foilage Nitrogen limitation factor from params file (clm4.5) Evergreen phenology option for CNPhenology (EXPERIMENTAL, UNSUPPORTED, and UNTESTED!) Carbon respiration option to burn off carbon when CN ratio is too high (do NOT use when FUN is on) (EXPERIMENTAL, UNSUPPORTED, and UNTESTED!) Minimum lake depth to increase non-molecular thermal diffusivities by the factor deepmixing_mixfact. Factor to increase non-molecular thermal diffusivities for lakes deeper than deepmixing_depthcrit to account for unresolved 3D processes. Set to 1 to Visible and Near-infrared albedo values for melting lakes. Albedo will relax to these values as temperature reaches melting when ice is present with no snow layers. Represents puddling, ice disintegration, and white ice. Set to alblak values (0.6, 0.4) to keep albedo constant for ice-covered lakes without snow layers. If surface water is active or not (deprecated -- will be removed) Allows user to tune the value of aereoxid. If set to FALSE, then use the value of aereoxid from the parameter file (set to 0.0, but may be tuned with values in the range {0.0,1.0}. If set to TRUE, then don't fix aere (see ch4Mod.F90). Default: .true. If TRUE, turn on methane biogeochemistry model for lake columns, using a simplified version of the CH4 submodel. (EXPERIMENTAL, UNSUPPORTED!) If TRUE, apply a limitation to methane production based on the soil pH dataset. Michaelis-Mentin maximum methane oxidation rate (mol/m^3-water/s), in the unsaturated zone. If TRUE, maintain constant soil carbon under lakes, and use the methane submodel simply to predict the net conversion of CO2 (via biological assimilation, decomposition, and methanogenesis) to CH4. If FALSE, transiently decompose initial soil carbon stock based on soil carbon dataset. NOTE: if FALSE, a new transient source of C is added to the climate system, so the coupled system will NOT conserve carbon in this mode if the methane model is coupled to the atmosphere. (EXPERIMENTAL, UNSUPPORTED, and UNTESTED!) Inundated fraction method type to use for the CH4 submodel (possibly affecting soil heterotrophic respiration and denitrification depending on the configuration), h2osfc ----------- Use prognostic saturated fraction h2osfc value calculated in Soil Hydrology ZWT_inversion ---- Use inversion of Prigent Satellite data to model ZWT TWS_inversion ---- Use inversion of Prigent Satellite data to model TWS Inversion options require additional data on fsurdat or use of stream_fldfilename_ch4finundated files. (h2osfc option is EXPERIMENTAL, UNSUPPORTED, and UNTESTED!) If TRUE, use the fine root carbon predicted by CN when calculating the aerenchyma area, rather than the parametrization based on annual NPP, aboveground NPP fraction, and LAI. (EXPERIMENTAL, UNSUPPORTED, and UNTESTED!) If TRUE, run the methane submodel decoupled from the atmosphere. The atmospheric methane concentration is prescribed by atmch4, the methane flux is not passed to the atmosphere, and the CO2 flux to the atmosphere is not adjusted for net methane production. NOTE: Currently this must be TRUE. (EXPERIMENTAL, UNSUPPORTED, and NOT functional!) Full pathname of time varying landuse data file. This causes the land-use types of the initial surface dataset to vary over time. If TRUE, apply transient natural PFTs from flanduse_timeseries file. (Only valid for transient runs, where there is a flanduse_timeseries file.) If TRUE, apply transient crops from flanduse_timeseries file. (Only valid for transient runs, where there is a flanduse_timeseries file.) If TRUE, apply transient lakes from flanduse_timeseries file. (Only valid for transient runs, where there is a flanduse_timeseries file.) If TRUE, apply transient urban from flanduse_timeseries file. (Only valid for transient runs, where there is a flanduse_timeseries file.) If TRUE, apply harvest from flanduse_timeseries file. (Only valid for transient runs, where there is a flanduse_timeseries file.) (Also, only valid for use_cn = true.) If TRUE, apply gross unrepresented landuse/land-cover change from flanduse_timeseries file. (Only valid for transient runs, where there is a flanduse_timeseries file.) (Also, only valid for use_cn = true.) If TRUE, reset baseline values of total column water and energy in the first step of the run. This should typically be set when transitioning from an offline spinup to a coupled run with transient glaciers, and *possibly* when transitioning from the spinup to the transient portion of a coupled run with transient glaciers; it should typically remain unset at other times. These baseline values are computed only for particular columns (currently, only for glacier columns). They provide values that are subtracted from the current state when counting total column water and energy. For glacier columns, these discount the water and energy contents in the "virtual" glacier ice, while adding representative amounts of water and energy in the non-explicitly-modeled soil beneath the ice. Subtracting these baselines reduces the fictitious dynbal fluxes generated when total grid cell water and energy changes as a result of dynamic column/landunit areas. These baseline values are initially computed based on cold start states. If this flag remains unset (.false.), these baseline values will remain fixed at their cold start values. This will conserve mass and energy, but may result in larger-than-desired dynbal energy fluxes (and, in principle, also larger dynbal water fluxes; but currently, the mass of glacier ice remains fixed over time, so dynbal water fluxes are fairly small regardless of whether this flag is ever set). To further reduce these dynbal fluxes, you can set this flag to .true. when starting a startup or hybrid run from a partially or entirely spun-up state. This will reset the baseline values based on the state at the start of this run. Note that setting this flag can break water and energy conservation! Specifically, any water and energy that has previously been added to or removed from states that contribute to these baselines (currently, (a) glacier ice and (b) soil water and energy in the vegetated landunit in the same grid cell as glaciers) will effectively be ignored when computing conservation corrections due to land cover change. Instead, only the change in states from this point forward will be considered. So, for example, this flag should NOT be set when transitioning from a historical run to a future scenario. This setting only impacts startup and hybrid runs; it has no effect in a continue run; it is an error for this to be set in a branch run. Furthermore, this setting has no effect in a cold start run. If TRUE, allow area changes at times other than the year boundary. This should only arise in some test configurations where we artifically create changes more frequently so that we can run short tests. This flag is only used for error-checking, not controlling any model behavior. Do not set this in a production (non-test) run unless you know what you're doing! If TRUE, set the dynbal water and energy fluxes to zero. This should typically only be done for testing: This is needed in some tests where we have daily rather than annual glacier dynamics: if we allow the true dynbal adjustment fluxes in those tests, we end up with sensible heat fluxes of thousands of W m-2 or more, which causes CAM to blow up. However, note that setting it to true will break water and energy conservation! If TRUE (which is the default), check consistency between year on the finidat file and the current model year. This check is only done for a transient run. If TRUE (which is the default), check consistency between pct_pft on the finidat file and pct_pft read from the surface dataset. This check is only done for a NON-transient run. If TRUE (which is the default), check consistency between pct_nat_pft on the flanduse_timeseries file and pct_nat_pft read from the surface dataset. Number of snow layers. Values less than 5 are mainly useful for testing, and should not be used for science. Maximum snow depth in mm H2O equivalent. Additional mass gains will be capped when this depth is exceeded. Changes in this value should possibly be accompanied by changes in: - nlevsno: larger values of h2osno_max should be accompanied by increases in nlevsno - glc_snow_persistence_max_days: large values of h2osno_max should generally have glc_snow_persistence_max_days = 0; small values of h2osno_max should generally have glc_snow_persistence_max_days > 0. Min snow thickness of layer 1 (top snow layer); values other than the default 0.01 have not been tested as of Sep 6, 2019 Min snow thickness of layer 2; values other than the default 0.015 have not been tested as of Sep 6, 2019; snow_dzmin of remaining layers is generated with the following recursive formula: dzmin(j) = dzmax_u(j-1) * 0.5_r8 Max snow thickness of layer 1 (top snow layer) when no layers beneath; values other than the default 0.03 have not been tested as of Sep 6, 2019 Max snow thickness of layer 2 when no layers beneath; values other than the default 0.07 have not been tested as of Sep 6, 2019; snow_dzmax_l of remaining layers is generated with the following recursive formula: dzmax_l(j) = dzmax_u(j) + dzmax_l(j-1) Max snow thickness of layer 1 (top snow layer) when layers beneath; values other than the default 0.02 have not been tested as of Sep 6, 2019 Max snow thickness of layer 2 when layers beneath; values other than the default 0.05 have not been tested as of Sep 6, 2019; snow_dzmax_u of remaining layers is generated with the following recursive formula: dzmax_u(j) = 2._r8 * dzmax_u(j-1) + 0.01_r8 Limit applied to integrated snowfall when determining changes in snow-covered fraction during melt (mm H2O) Only applies when using the SwensonLawrence2012 snow cover fraction method SCA shape parameter for glc_mec (glacier multiple elevation class) columns For most columns, n_melt is based on the standard deviation of 1km topography in the grid cell; but glc_mec columns already account for subgrid topographic variability through their use of multiple elevation classes; thus, to avoid double-accounting for topographic variability in these columns, we use a fixed value of n_melt. Only applies when using the SwensonLawrence2012 snow cover fraction method If TRUE, the density of new snow depends on wind speed, and there is also wind-dependent snow compaction. Method used to compute snow overburden compaction Anderson1976 -- older method, default in CLM45 Vionnet2012 --- newer method, default in CLM50 Snow density method to use for low temperatures (below -15C) TruncatedAnderson1976 -- Truncate the Anderson-1976 equation at the value for -15C Slater2017 ------------- Use equation from Slater that increases snow density for very cold temperatures (Arctic, Antarctic) Upper Limit on Destructive Metamorphism Compaction [kg/m3] Snow compaction overburden exponential factor (1/K) Not used for snow_overburden_compaction_method=Vionnet2012 If set to .true., then reset the snow pack over non-glacier columns to a small value. This is useful when transitioning from a spinup under one set of atmospheric forcings to a run under a different set of atmospheric forcings: By resetting too-large snow packs, we make it more likely that points will remain only seasonally snow-covered under the new atmospheric forcings. (This is particularly true in a coupled run, where starting with a too-large snow pack can cool the atmosphere, thus maintaining the too-large snow pack.) WARNING: Setting this to .true. will break water conservation for approximately the first day of the new run. This is by design: The excess snow is completely removed from the system. If set to .true., then reset the snow pack over glacier columns to a small value. This is useful when transitioning from a spinup under one set of atmospheric forcings to a run under a different set of atmospheric forcings: By resetting too-large snow packs, we make it more likely that points will remain only seasonally snow-covered under the new atmospheric forcings. (This is particularly true in a coupled run, where starting with a too-large snow pack can cool the atmosphere, thus maintaining the too-large snow pack.) See also reset_snow_glc_ela, which controls the elevation below which glacier columns are reset. WARNING: Setting this to .true. will break water conservation for approximately the first day of the new run. This is by design: The excess snow is completely removed from the system. WARNING: This variable is intended for short test runs, and generally should not be used for scientific production runs. By resetting snow below a given elevation, you risk forcing the system to evolve differently in areas below and above reset_snow_glc_ela. Only relevant if reset_snow_glc is .true. When resetting snow pack over glacier columns, one can choose to do this over all glacier columns, or only those below a certain elevation. A typical use case is to reset only those columns that have a seasonal snow pack in the real world, i.e. SMB less than 0, also known as the equilibrium line altitude (ELA). This parameter sets a single global ELA value. By setting this parameter to a large value (i.e. 10000 m), all glacier columns will be reset. WARNING: This variable is intended for short test runs, and generally should not be used for scientific production runs. By resetting snow below a given elevation, you risk forcing the system to evolve differently in areas below and above reset_snow_glc_ela. Parameterization to use for snow cover fraction NiuYang2007: Niu and Yang 2007 SwensonLawrence2012: Swenson and Lawrence 2012 Parameterization to use for snow thermal conductivity If .true., add water tracers needed to perform water tracer consistency checks. These consistency checks ensure that all water tracers are updated to remain in-sync with the related bulk quantities. If .true., run with water isotopes Parameterization/parameters to use for surface roughness ZengWang2007: Zeng and Wang 2007 Meier2022: Meier et al. in prep. 2022 If FALSE use constant snow z0m If TRUE use parameterization of snow z0m as a function of accumulated snow melt of Brock et al. (2006) If FALSE (which is the default): If an output type cannot be found in the input for initInterp, code aborts If TRUE: If an output type cannot be found in the input, fill with closest natural veg column (using bare soil for patch-level variables) NOTE: Natural vegetation and crop landunits always behave as if this were true. e.g., if we can't find a column with the same type as a given crop column in the output, then we always fill with the closest natural veg patch / column, regardless of the value of this flag. So interpolation from non-crop to crop cases can be done without setting this flag. Method to use for init_interp. Only applies when use_init_interp = .true. 'general': The general-purpose method that can be used when changing grids, configurations, etc. This starts off with subgrid areas taken from the surface dataset. 'use_finidat_areas': This starts off with subgrid areas taken from the input finidat file. This is needed to achieve bit-for-bit results in a coupled case (where areas in initialization impact initial fields sent to the atmosphere) (but using the 'general' method will typically have only a very minor impact on results in this case). For this method to work, the input finidat file needs to be at the same resolution as the current configuration. So this is a less general form of init_interp. However, it can be used in cases where the only difference is in internal memory allocation. In order to catch possible problems, this uses a different algorithm for finding the input point for each output point, which ensures that each active output point is associated with exactly one input point with the same latitude, longitude and type. This method requires (a) the same grid for input and output, within roundoff; (b) any non-zero-weight point in the input must have memory allocated for it in this grid cell in the output (this will be satisfied if the point is non-zero-weight on the surface dataset or if it's a point for which we allocate memory even for zero-weight points); (c) any active point in the output (based on the surface dataset and rules for determining active points) must have a matching point in this grid cell in the input. (Note that this generally can NOT be used when transitioning from a spinup run to a transient run, because spinup runs typically have irrigation off and transient runs have irrigation on, and the presence/absence of irrigation affects the subgrid structure; if it weren't for that difference, then this option would be useful for this use case.) If TRUE turn on the excess ice physics, (Lee et al., 2014; Cai et al., 2020) If TRUE and use_excess_ice is TRUE, use the excess ice stream to determine the initial values of the excess ice field if FALSE and use_excess_ice is TRUE, expect excess ice to come from the initial conditions or restart file Expect to be FALSE is use_excess_ice is FALSE Filename of input stream data for excess ice data mesh filename of input stream data for excess ice Mapping method from excess ice input stream data to the model resolution bilinear = bilinear interpolation nn = nearest neighbor none = no interpolation Whether to till crop soil, and if so, with what intensity. Toggle to use original (Graham et al. 2021) tillage logic, with bug for seasons crossing into a new calendar year Maximum depth to till soil (m). Default 0.26; original (Graham et al., 2021) value was unintentionally 0.32.