Model variables¶

ADELM organizes runtime variables into a small set of formal container types. The goal is to keep process code, model outputs, and API documentation aligned around a consistent variable system.

Tensor dimensions¶

All runtime tensors share a common batch dimension called n_entities, which indexes the locations being simulated simultaneously - flux tower sites, grid cells, or any other set of spatial units. The other common dimensions are:

Symbol	Meaning
`n_entities`	number of locations (sites, grid cells, …) in the batch
`n_time`	number of time steps
`n_layers`	number of soil layers

For example, a driver tensor has shape [n_entities, n_time] and a soil moisture state tensor has shape [n_entities, n_layers].

Note on input files: ADELM reads NetCDF input files that use a site dimension. Internally this dimension is always referred to as n_entities so that the same model code works equally for point sites, regional grids, or other spatial discretisations.

Variable containers¶

drivers External forcing data. These can vary in time, but they are not modified by the model itself.
attris Static location characteristics (e.g. climate indices, soil texture, vegetation cover fractions) used as input features for the nn_feature_based neural parameterization. Not modified during simulation.
states Prognostic variables advanced in time by the model.
fluxes Mass, energy, or carbon exchange rates diagnosed by model processes.
diagnos Derived timestep-wise variables used by the calculation chain, but not advanced by time integration. In practice, diagnos is used for process variables that are part of the model calculation chain or are treated as standard process diagnostics in outputs.
params Time-invariant model parameters controlling process behaviour.
consts Physical constants, unit-conversion constants, and a small number of numerical constants.
errors Residual and conservation diagnostics used to check numerical and physical consistency.

ADELM also supports a system-level debugs output container.

debugs is not part of the formal variable registry
debugs variables are therefore not listed in the variable tables below
users and developers can write custom analysis variables directly in processes or parameterization code using a simple pattern such as debugs["my_variable"] = value
in practice, debugs is used for explanatory quantities that help interpret a calculation but are not consumed downstream

Drivers¶

External dynamic forcing data used by the model. Drivers may vary from timestep to timestep, but the model does not update them.

See also

See model.variables.drivers.

Name	Units	Description	Relations
`co2_ppm`	`ppm`	Atmospheric carbon dioxide concentration.	Used by: `calculate_gpp`
`cosine_solar_zenith`	`-`	Cosine of the solar zenith angle.	Produced by: `compute_cosine_solar_zenith_series` Used by: `calculate_optical_properties`
`lai`	`m2 m-2`	Leaf area index.	Used by: `calculate_optical_properties` `calculate_aerodynamic_exchange` `calculate_jarvis_gs` `calculate_gpp` `calculate_canopy_liquid_hydrology`
`lwdown_Wm2`	`W m-2`	Downward longwave (infrared) radiation at the surface.	Used by: `calculate_longwave_balance`
`pr_mmday`	`mm day-1`	Total daily precipitation as liquid-water equivalent.	Used by: `calculate_precipitation_phase`
`swdown_Wm2`	`W m-2`	Downward shortwave radiation at the surface.	Used by: `calculate_shortwave_balance`
`ta_degC`	`degC`	Near-surface air temperature.	Used by: `calculate_timestep_and_thermodynamics` `calculate_longwave_balance` `calculate_soil_conductivity` `calculate_jarvis_gs` `calculate_gpp` `calculate_soil_hydrology` `calculate_soil_surface_vapour_gradient`
`ta_max_degC`	`degC`	Daily maximum near-surface air temperature.	Used by: `calculate_precipitation_phase` `calculate_soil_surface_vapour_gradient`
`ta_min_degC`	`degC`	Daily minimum near-surface air temperature.	Used by: `calculate_precipitation_phase` `calculate_soil_surface_vapour_gradient`
`vpd_kPa`	`kPa`	Vapour pressure deficit.	Used by: `calculate_timestep_and_thermodynamics` `calculate_jarvis_gs` `calculate_soil_surface_vapour_gradient` `calculate_potential_canopy_liquid_evaporation` `calculate_potential_canopy_transpiration`
`wind_ms`	`m s-1`	Wind speed at reference height (10 m).	Used by: `calculate_aerodynamic_exchange`

States¶

Prognostic model state that evolves through time and is advanced by the model.

See also

See model.variables.states.

Name	Units	Description	Relations
`canopy_liquid_interception_storage`	`mm`	Liquid water stored on wet canopy surfaces.	Produced by: `calculate_canopy_liquid_hydrology`
`canopy_solid_interception_storage`	`mm`	Snow water equivalent stored on the canopy.	Produced by: `calculate_canopy_solid_hydrology`
`snow_water_storage`	`mm`	Snow water equivalent stored in the surface snowpack.	Produced by: `calculate_snow_hydrology`
`soil_moisture`	`m3 m-3`	Volumetric water content of each soil layer.	Produced by: `calculate_soil_hydrology` Used by: `calculate_soil_conductivity` `calculate_soil_water_potential` `calculate_root_fraction_profile` `calculate_soil_surface_resistance` `calculate_soil_hydrology`

Fluxes¶

Mass, energy, or carbon exchange rates computed by model processes.

See also

See model.variables.fluxes.

Name	Units	Description	Relations
`canopy_liquid_evaporation_mmday`	`mm day-1`	Water flux evaporated from wet canopy surfaces.	Produced by: `calculate_canopy_liquid_hydrology` Used by: `calculate_latent_heat_flux` `calculate_soil_hydrology`
`canopy_liquid_interception_mmday`	`mm day-1`	Liquid water flux intercepted by the canopy.	Produced by: `calculate_canopy_liquid_hydrology`
`canopy_net_lwrad_Wm2`	`W m-2`	Longwave radiative flux absorbed by the canopy.	Produced by: `calculate_longwave_balance` Used by: `calculate_potential_canopy_liquid_evaporation` `calculate_potential_canopy_transpiration`
`canopy_net_radiation_Wm2`	`W m-2`	Net radiative flux at the canopy surface.	Produced by: `calculate_potential_canopy_liquid_evaporation` `calculate_potential_canopy_transpiration`
`canopy_net_swrad_Wm2`	`W m-2`	Shortwave radiative flux absorbed by the canopy.	Produced by: `calculate_shortwave_balance` Used by: `calculate_potential_canopy_liquid_evaporation` `calculate_potential_canopy_transpiration`
`canopy_solid_interception_mmday`	`mm day-1`	Snow water flux intercepted by the canopy.	Produced by: `calculate_canopy_solid_hydrology`
`canopy_solid_sublimation_mmday`	`mm day-1`	Water flux sublimated from snow intercepted on the canopy.	Produced by: `calculate_canopy_solid_hydrology` Used by: `calculate_latent_heat_flux` `calculate_soil_hydrology`
`canopy_solid_unload_mmday`	`mm day-1`	Snow water flux released from the canopy.	Produced by: `calculate_canopy_solid_hydrology`
`canopy_transpiration_mmday`	`mm day-1`	Water flux from the soil column to the atmosphere through plants.	Produced by: `calculate_soil_hydrology` Used by: `calculate_latent_heat_flux`
`gpp_gCm2day`	`gC m-2 day-1`	Gross primary productivity.	Produced by: `calculate_gpp`
`gravitational_drainage_mmday`	`mm day-1`	Downward water flux leaving each soil layer under gravity.	Produced by: `calculate_soil_hydrology`
`incoming_par_Wm2`	`W m-2`	Incoming photosynthetically active radiation at the canopy top.	Produced by: `calculate_shortwave_balance` Used by: `calculate_jarvis_gs`
`infiltration_mmday`	`mm day-1`	Water flux entering each soil layer from above.	Produced by: `calculate_soil_hydrology`
`latent_heat_flux_Wm2`	`W m-2`	Latent heat flux associated with evaporation and sublimation.	Produced by: `calculate_latent_heat_flux`
`leaf_apar_Wm2`	`W m-2`	Photosynthetically active radiation absorbed by leaf surfaces.	Produced by: `calculate_shortwave_balance` Used by: `calculate_gpp`
`lwdown_below_canopy_Wm2`	`W m-2`	Downward longwave radiation below the vegetation canopy.	Produced by: `calculate_longwave_balance`
`lwup_above_canopy_Wm2`	`W m-2`	Upward longwave radiation above the vegetation canopy.	Produced by: `calculate_longwave_balance`
`lwup_below_canopy_Wm2`	`W m-2`	Upward longwave radiation below the vegetation canopy.	Produced by: `calculate_longwave_balance`
`net_lwrad_Wm2`	`W m-2`	Net longwave radiative flux absorbed by the land surface.	Produced by: `calculate_longwave_balance`
`net_swrad_Wm2`	`W m-2`	Net shortwave radiative flux absorbed by the land surface.	Produced by: `calculate_shortwave_balance`
`rainfall_mmday`	`mm day-1`	Liquid precipitation reaching the canopy top.	Produced by: `calculate_precipitation_phase` Used by: `calculate_canopy_liquid_hydrology`
`root_water_uptake_mmday`	`mm day-1`	Water flux extracted from each soil layer by roots.	Produced by: `calculate_soil_hydrology`
`runoff_mmday`	`mm day-1`	Water flux leaving the land surface as runoff.	Produced by: `calculate_soil_hydrology`
`snow_sublimation_mmday`	`mm day-1`	Water flux sublimated from the ground snowpack.	Produced by: `calculate_snow_hydrology` Used by: `calculate_latent_heat_flux` `calculate_soil_hydrology`
`snowfall_mmday`	`mm day-1`	Solid precipitation reaching the canopy top.	Produced by: `calculate_precipitation_phase` Used by: `calculate_canopy_solid_hydrology`
`snowfall_to_ground_mmday`	`mm day-1`	Total snowfall reaching the ground, including direct throughfall and canopy unloading.	Produced by: `calculate_canopy_solid_hydrology` Used by: `calculate_snow_hydrology`
`snowmelt_mmday`	`mm day-1`	Water flux released from the snowpack by melting.	Produced by: `calculate_snow_hydrology` Used by: `calculate_soil_hydrology`
`soil_evaporation_mmday`	`mm day-1`	Water flux evaporated from the top soil layer.	Produced by: `calculate_soil_hydrology` Used by: `calculate_latent_heat_flux`
`soil_net_lwrad_Wm2`	`W m-2`	Longwave radiative flux absorbed by the soil surface.	Produced by: `calculate_longwave_balance` Used by: `calculate_potential_surface_evaporation`
`soil_net_radiation_Wm2`	`W m-2`	Net radiative flux at the soil surface.	Produced by: `calculate_potential_surface_evaporation`
`soil_net_swrad_Wm2`	`W m-2`	Shortwave radiative flux absorbed by the soil surface (visible plus near-infrared).	Produced by: `calculate_shortwave_balance` Used by: `calculate_potential_surface_evaporation`
`throughfall_from_canopy_mmday`	`mm day-1`	Liquid precipitation reaching the soil surface without canopy interception.	Produced by: `calculate_canopy_liquid_hydrology` Used by: `calculate_soil_hydrology`
`total_et_mmday`	`mm day-1`	Total evapotranspiration water flux to the atmosphere.	Produced by: `calculate_soil_hydrology`
`underflow_mmday`	`mm day-1`	Downward water flux leaving the base of the soil column.	Produced by: `calculate_soil_hydrology`

Diagnostics¶

Derived timestep-wise variable used in model calculations, reporting, or output, but not advanced by time integration.

This container is used for variables that remain part of the runtime process description, even when they are not prognostic states. Internal limitation factors, split numerators and denominators, and similar analysis-only quantities are better placed in debugs.

See also

See model.variables.diagnos.

Name	Units	Description	Relations
`above_canopy_aerodynamic_conductance`	`m s-1`	Aerodynamic conductance for water vapour transport from the canopy top to the reference height.	Produced by: `calculate_aerodynamic_exchange` Used by: `calculate_potential_canopy_liquid_evaporation` `calculate_potential_canopy_transpiration`
`air_density`	`kg m-3`	Mass of air per unit volume.	Produced by: `calculate_timestep_and_thermodynamics` Used by: `calculate_potential_surface_evaporation`
`air_molar_density`	`mol m-3`	Molar concentration of air.	Produced by: `calculate_timestep_and_thermodynamics` Used by: `calculate_gpp` `calculate_potential_canopy_transpiration`
`canopy_aerodynamic_conductance`	`m s-1`	Effective aerodynamic conductance for water vapour transport between the canopy and the atmosphere.	Produced by: `calculate_aerodynamic_exchange` Used by: `calculate_gpp`
`canopy_diffuse_optical_depth_scale`	`-`	Average inverse optical depth for diffuse radiation.	Produced by: `calculate_optical_properties` Used by: `calculate_shortwave_balance`
`canopy_diffuse_upscatter_parameter_nir`	`-`	Upscatter parameter for diffuse radiation in the near-infrared band.	Produced by: `calculate_optical_properties` Used by: `calculate_shortwave_balance`
`canopy_diffuse_upscatter_parameter_vis`	`-`	Upscatter parameter for diffuse radiation in the visible band.	Produced by: `calculate_optical_properties` Used by: `calculate_shortwave_balance`
`canopy_direct_beam_extinction_coefficient`	`-`	Optical depth of the direct beam per unit leaf and stem area index.	Produced by: `calculate_optical_properties` Used by: `calculate_shortwave_balance`
`canopy_direct_beam_upscatter_parameter_nir`	`-`	Upscatter parameter for direct beam radiation in the near-infrared band.	Produced by: `calculate_optical_properties` Used by: `calculate_shortwave_balance`
`canopy_direct_beam_upscatter_parameter_vis`	`-`	Upscatter parameter for direct beam radiation in the visible band.	Produced by: `calculate_optical_properties` Used by: `calculate_shortwave_balance`
`canopy_single_scattering_albedo_nir`	`-`	Single-scattering albedo of the canopy in the near-infrared band.	Produced by: `calculate_optical_properties` Used by: `calculate_shortwave_balance`
`canopy_single_scattering_albedo_vis`	`-`	Single-scattering albedo of the canopy in the visible band.	Produced by: `calculate_optical_properties` Used by: `calculate_shortwave_balance`
`canopy_stomatal_conductance`	`mmol H2O m-2 s-1`	Canopy-scale stomatal conductance to water vapour.	Produced by: `calculate_jarvis_gs` Used by: `calculate_gpp` `calculate_potential_canopy_transpiration`
`ground_diffuse_albedo_nir`	`-`	Effective ground albedo for diffuse radiation in the near-infrared band, accounting for snow cover.	Produced by: `calculate_optical_properties` Used by: `calculate_shortwave_balance`
`ground_diffuse_albedo_vis`	`-`	Effective ground albedo for diffuse radiation in the visible band, accounting for snow cover.	Produced by: `calculate_optical_properties` Used by: `calculate_shortwave_balance`
`ground_direct_beam_albedo_nir`	`-`	Effective ground albedo for direct beam radiation in the near-infrared band, accounting for snow cover.	Produced by: `calculate_optical_properties` Used by: `calculate_shortwave_balance`
`ground_direct_beam_albedo_vis`	`-`	Effective ground albedo for direct beam radiation in the visible band, accounting for snow cover.	Produced by: `calculate_optical_properties` Used by: `calculate_shortwave_balance`
`kinematic_viscosity_of_air`	`m2 s-1`	Ratio of dynamic viscosity to air density.	Produced by: `calculate_timestep_and_thermodynamics` Used by: `calculate_aerodynamic_exchange`
`latent_heat_of_vaporization`	`J kg-1`	Energy required to vaporize one kilogram of liquid water.	Produced by: `calculate_timestep_and_thermodynamics` Used by: `calculate_potential_surface_evaporation` `calculate_potential_canopy_liquid_evaporation` `calculate_potential_canopy_sublimation` `calculate_potential_canopy_transpiration` `calculate_latent_heat_flux`
`leaf_boundary_layer_conductance`	`m s-1`	Bulk conductance for water vapour across the laminar boundary layer of canopy leaves.	Produced by: `calculate_aerodynamic_exchange` Used by: `calculate_potential_canopy_liquid_evaporation` `calculate_potential_canopy_transpiration`
`potential_canopy_liquid_evaporation`	`mm day-1`	Atmospheric demand for evaporation from wet canopy surfaces.	Produced by: `calculate_potential_canopy_liquid_evaporation` Used by: `calculate_potential_canopy_sublimation` `calculate_canopy_liquid_hydrology`
`potential_canopy_sublimation`	`mm day-1`	Atmospheric demand for sublimation of solid-phase water stored on the canopy.	Produced by: `calculate_potential_canopy_sublimation` Used by: `calculate_canopy_solid_hydrology`
`potential_canopy_transpiration`	`mm day-1`	Maximum water vapour flux from canopy leaves to the atmosphere.	Produced by: `calculate_potential_canopy_transpiration` Used by: `calculate_soil_hydrology`
`potential_snow_sublimation`	`mm day-1`	Atmospheric demand for sublimation from the ground snowpack.	Produced by: `calculate_potential_snow_sublimation` Used by: `calculate_snow_hydrology`
`potential_surface_evaporation`	`mm day-1`	Atmospheric demand for evaporation from the snow-free soil surface.	Produced by: `calculate_potential_surface_evaporation` Used by: `calculate_potential_snow_sublimation` `calculate_soil_hydrology`
`psychrometric_constant`	`kPa K-1`	Ratio of sensible to latent heat flux for a wet surface at constant pressure.	Produced by: `calculate_timestep_and_thermodynamics` Used by: `calculate_potential_surface_evaporation` `calculate_potential_canopy_liquid_evaporation` `calculate_potential_canopy_transpiration`
`root_zone_soil_water_potential`	`MPa`	Mean soil water potential of the root zone.	Produced by: `calculate_soil_plant_water_supply` Used by: `calculate_jarvis_gs`
`saturation_vapour_pressure_slope`	`kPa K-1`	Rate of change of saturation vapour pressure with temperature.	Produced by: `calculate_timestep_and_thermodynamics` Used by: `calculate_potential_surface_evaporation` `calculate_potential_canopy_liquid_evaporation` `calculate_potential_canopy_transpiration`
`snow_cover_fraction`	`-`	Fraction of the ground surface covered by snow.	Produced by: `calculate_optical_properties` Used by: `calculate_shortwave_balance` `calculate_soil_surface_resistance`
`soil_aerodynamic_conductance`	`m s-1`	Aerodynamic conductance for water vapour transport between the soil surface and the canopy air.	Produced by: `calculate_aerodynamic_exchange` Used by: `calculate_potential_surface_evaporation`
`soil_conductivity`	`mm h-1`	Effective hydraulic conductivity of each soil layer.	Produced by: `calculate_soil_conductivity` Used by: `calculate_soil_plant_water_supply`
`soil_surface_conductance`	`m s-1`	Soil surface conductance to water vapour.	Produced by: `calculate_soil_surface_resistance` Used by: `calculate_potential_surface_evaporation`
`soil_to_air_vapour_pressure_gradient`	`kPa`	Difference between soil-surface vapour pressure and near-surface air vapour pressure.	Produced by: `calculate_soil_surface_vapour_gradient` Used by: `calculate_potential_surface_evaporation`
`soil_water_potential`	`MPa`	Soil water potential across all soil layers.	Produced by: `calculate_soil_water_potential` Used by: `calculate_soil_plant_water_supply` `calculate_soil_surface_vapour_gradient`
`vegetation_area_index`	`m2 m-2`	Total vegetation area index: one-sided leaf area index plus stem area index.	Produced by: `calculate_optical_properties` Used by: `calculate_shortwave_balance` `calculate_canopy_solid_hydrology`
`water_uptake_fraction`	`-`	Fraction of total root water uptake in each soil layer.	Produced by: `calculate_soil_plant_water_supply` Used by: `calculate_soil_hydrology`
`water_vapour_diffusivity`	`m2 s-1`	Molecular diffusivity of water vapour in air.	Produced by: `calculate_timestep_and_thermodynamics` Used by: `calculate_aerodynamic_exchange`

Parameters¶

Time-invariant model parameter controlling process behaviour.

See also

See model.variables.params.

fixed: Parameter value fixed during a run and supplied as a scalar in parameterization.parameters.<name>.value.
data: Static parameter value loaded from data.mapping.params. For parameters registered with source data, the mapping must be provided when parameter files are used.
pft_based: Parameter value computed as a PFT-fraction-weighted average from the fractional vegetation cover data (fcover) and PFT_LOOKUP.txt. Requires fcover input to be provided.
derived: Parameter value computed from other parameters by a physics-based routine (e.g. pedotransfer functions deriving hydraulic properties from soil texture).
nn_global: Globally shared trainable parameter. A single value is learned during calibration and applied uniformly across all locations. Declared in config.yaml with parameterization.parameters.<name>.source: nn_global.
nn_feature_based: Location-specific trainable parameter predicted by a multi-layer perceptron (MLP) from location attributes. One value is produced per location. Declared with parameterization.parameters.<name>.source: nn_feature_based.

The nn_global and nn_feature_based source types must be declared explicitly in the parameterization.parameters block of config.yaml. They are not inferred from the registry.

Each parameter has exactly one active source. If you specify a parameter in Configuration, that explicit source overrides the registry default source for that parameter. A parameter must not be assigned multiple sources at the same time.

data parameters

Name	Units	Description	Relations
`latitude_deg`	`deg`	Geographic latitude of the site.	Used by: `compute_cosine_solar_zenith_series`
`longitude_deg`	`deg`	Geographic longitude of the site.	Used by: `compute_cosine_solar_zenith_series`
`soil_bulk_density`	`g cm-3`	Bulk density of the soil.	Used by: `calculate_soil_parameters_pedotransfer`
`soil_clay_fraction`	`-`	Clay mass fraction of the soil.	Used by: `calculate_soil_parameters_pedotransfer`
`soil_organic_matter_fraction`	`-`	Organic matter fraction of the soil.	Used by: `calculate_soil_parameters_pedotransfer`
`soil_sand_fraction`	`-`	Sand mass fraction of the soil.	Used by: `calculate_soil_parameters_pedotransfer`

derived parameters

Name	Units	Description	Relations
`root_fraction`	`-`	Normalised root fraction per soil layer.	Produced by: `calculate_root_fraction_profile` Used by: `calculate_soil_plant_water_supply`
`soil_brooks_corey_a`	`MPa`	Air-entry pressure coefficient in the Brooks-Corey soil water retention curve.	Produced by: `calculate_soil_parameters_pedotransfer` Used by: `calculate_soil_water_potential`
`soil_brooks_corey_b`	`-`	Pore-size distribution index in the Brooks-Corey soil water retention curve.	Produced by: `calculate_soil_parameters_pedotransfer` Used by: `calculate_soil_water_potential` `calculate_soil_conductivity` `calculate_soil_hydrology`
`soil_brooks_corey_bubbling_head`	`MPa`	Brooks-Corey air-entry (bubbling) water potential of the soil.	Produced by: `calculate_soil_parameters_pedotransfer` Used by: `calculate_soil_water_potential` `calculate_soil_hydrology`
`soil_field_capacity`	`m3 m-3`	Volumetric soil moisture content at field capacity.	Produced by: `calculate_soil_parameters_pedotransfer` Used by: `calculate_soil_hydrology`
`soil_saturated_hydraulic_conductivity`	`mm h-1`	Saturated hydraulic conductivity.	Produced by: `calculate_soil_parameters_pedotransfer` Used by: `calculate_soil_conductivity` `calculate_soil_hydrology`
`soil_saturated_moisture`	`m3 m-3`	Saturated volumetric soil moisture content.	Produced by: `calculate_soil_parameters_pedotransfer` Used by: `calculate_soil_conductivity` `calculate_soil_water_potential` `calculate_soil_surface_resistance` `calculate_soil_hydrology`
`soil_wilting_point`	`m3 m-3`	Volumetric soil moisture content at wilting point (1500 kPa).	Produced by: `calculate_soil_parameters_pedotransfer` Used by: `calculate_soil_surface_resistance`

fixed parameters

Name	Value	Units	Description	Relations
`canopy_interception_capacity_coefficient`	`0.2`	`mm (m2 m-2)-1`	Maximum liquid water the canopy can hold per unit leaf area index.	Used by: `calculate_canopy_liquid_hydrology`
`canopy_solid_interception_capacity_coefficient`	`1.0`	`mm (m2 m-2)-1`	Maximum snow water equivalent the canopy can hold per unit vegetation area index.	Used by: `calculate_canopy_solid_hydrology`
`direct_beam_fraction`	`0.5`	`-`	Fraction of incoming shortwave radiation that is direct beam.	Used by: `calculate_shortwave_balance`
`jarvis_max_stomatal_conductance`	`500.0`	`mmol H2O m-2 s-1`	Upper bound on leaf stomatal conductance to water vapour.	Used by: `calculate_jarvis_gs`
`jarvis_min_stomatal_conductance`	`10.0`	`mmol H2O m-2 s-1`	Lower bound on leaf stomatal conductance to water vapour.	Used by: `calculate_jarvis_gs`
`jarvis_temperature_curvature`	`0.0016`	`degC-2`	Quadratic sensitivity of stomatal conductance to air temperature departure from the optimum.	Used by: `calculate_jarvis_gs`
`jarvis_temperature_optimum`	`25.0`	`degC`	Air temperature at which stomatal conductance reaches its temperature-response maximum.	Used by: `calculate_jarvis_gs`
`jarvis_water_potential_midpoint`	`-0.3`	`MPa`	Soil water potential at which stomatal conductance is reduced by half.	Used by: `calculate_jarvis_gs`
`jarvis_water_potential_steepness`	`3.0`	`MPa-1`	Steepness of the sigmoid stomatal response to soil water potential.	Used by: `calculate_jarvis_gs`
`light_use_efficiency`	`1.2`	`gC MJ-1`	Efficiency of converting leaf-absorbed photosynthetically active radiation into gross carbon assimilation.	Used by: `calculate_gpp`
`photosynthesis_capacity_coefficient`	`25.0`	`gC m-2 leaf day-1`	Leaf-scale photosynthetic assimilation capacity at optimum temperature.	Used by: `calculate_gpp`
`photosynthesis_colimitation_curvature`	`0.95`	`-`	Colimitation curvature of photosynthesis by light and diffusion capacity.	Used by: `calculate_gpp`
`photosynthesis_temperature_kurtosis`	`0.183`	`-`	Shape parameter of the photosynthesis temperature response.	Used by: `calculate_gpp`
`photosynthesis_temperature_maximum`	`56.0`	`degC`	Upper temperature bound of the photosynthesis temperature response.	Used by: `calculate_gpp`
`photosynthesis_temperature_optimum`	`30.0`	`degC`	Optimum temperature of the photosynthesis temperature response.	Used by: `calculate_gpp`
`snow_cover_scale`	`25.0`	`mm`	Characteristic snow water equivalent at which half the ground surface is snow-covered.	Used by: `calculate_optical_properties`
`snow_melt_coefficient`	`3.0`	`mm degC-1 day-1`	Degree-day snowmelt coefficient: melt per degree above the freeze threshold per day.	Used by: `calculate_snow_hydrology`
`snow_nir_albedo`	`0.65`	`-`	Snow-covered surface albedo in the near-infrared band.	Used by: `calculate_optical_properties`
`snow_nir_omega`	`0.4`	`-`	Single-scattering albedo of intercepted canopy snow in the near-infrared band.	Used by: `calculate_optical_properties`
`snow_vis_albedo`	`0.95`	`-`	Snow-covered surface albedo in the visible band.	Used by: `calculate_optical_properties`
`snow_vis_omega`	`0.8`	`-`	Single-scattering albedo of intercepted canopy snow in the visible band.	Used by: `calculate_optical_properties`
`soil_freeze_transition_sharpness`	`5.0`	`-`	Sharpness of the temperature-driven freeze reduction of soil hydraulic conductivity.	Used by: `calculate_soil_conductivity`
`soil_freeze_transition_temperature`	`1.0`	`degC`	Temperature threshold below which freezing reduces soil hydraulic conductivity.	Used by: `calculate_soil_conductivity`
`soil_infiltration_shape_parameter`	`0.2`	`-`	Shape parameter of the variable infiltration capacity curve.	Used by: `calculate_soil_hydrology`
`soil_nir_albedo`	`0.29`	`-`	Snow-free soil albedo in the near-infrared band.	Used by: `calculate_optical_properties`
`soil_roughness_length`	`0.01`	`m`	Aerodynamic roughness length for momentum over soil.	Used by: `calculate_aerodynamic_exchange`
`soil_surface_resistance_moisture_sensitivity`	`4.225`	`-`	Exponential sensitivity coefficient of soil surface resistance to top-layer soil moisture.	Used by: `calculate_soil_surface_resistance`
`soil_vis_albedo`	`0.15`	`-`	Snow-free soil albedo in the visible band.	Used by: `calculate_optical_properties`
`surface_emissivity`	`0.96`	`-`	Broadband thermal infrared emissivity of the soil or snow surface.	Used by: `calculate_longwave_balance`
`vis_fraction_of_shortwave`	`0.5`	`-`	Fraction of incoming shortwave radiation in the visible (400-700 nm) band.	Used by: `calculate_shortwave_balance`

pft_based parameters

Name	Units	Description	Relations
`canopy_height`	`m`	Canopy height.	Used by: `calculate_aerodynamic_exchange`
`canopy_leaf_width`	`m`	Characteristic leaf width.	Used by: `calculate_aerodynamic_exchange`
`jarvis_radiation_half_saturation`	`W m-2`	Absorbed PAR at which the stomatal radiation response reaches half its maximum.	Used by: `calculate_jarvis_gs`
`jarvis_vpd_sensitivity`	`kPa-1`	Sensitivity of stomatal conductance to vapour pressure deficit.	Used by: `calculate_jarvis_gs`
`leaf_angle_dist_index`	`-`	Leaf angle distribution index, ranging from -1 (vertical leaves) to +1 (horizontal leaves).	Used by: `calculate_optical_properties`
`leaf_nir_reflectance`	`-`	Leaf reflectance in the near-infrared band.	Used by: `calculate_optical_properties`
`leaf_nir_transmittance`	`-`	Leaf transmittance in the near-infrared band.	Used by: `calculate_optical_properties`
`leaf_vis_reflectance`	`-`	Leaf reflectance in the visible band.	Used by: `calculate_optical_properties`
`leaf_vis_transmittance`	`-`	Leaf transmittance in the visible band.	Used by: `calculate_optical_properties`
`plant_minimum_leaf_water_potential`	`MPa`	Minimum leaf water potential below which soil-plant water transport ceases.	Used by: `calculate_soil_plant_water_supply`
`plant_root_distribution_shape`	`-`	Shape parameter of the exponential vertical root-fraction distribution.	Used by: `calculate_root_fraction_profile`
`stem_area_index`	`m2 m-2`	One-sided stem area index.	Used by: `calculate_optical_properties`
`stem_nir_reflectance`	`-`	Stem reflectance in the near-infrared band.	Used by: `calculate_optical_properties`
`stem_nir_transmittance`	`-`	Stem transmittance in the near-infrared band.	Used by: `calculate_optical_properties`
`stem_vis_reflectance`	`-`	Stem reflectance in the visible band.	Used by: `calculate_optical_properties`
`stem_vis_transmittance`	`-`	Stem transmittance in the visible band.	Used by: `calculate_optical_properties`

Constants¶

Constant value used by the model that does not change during simulation.

See also

See model.variables.consts.

physical: Physical laws or well-established physical ratios (e.g. latent heat of vaporization, Stefan-Boltzmann constant).
model: Structural constants specific to the model formulation (e.g. discretization counts, fixed scaling coefficients).

model constants

Name	Value	Units	Description	Relations
`numerical_epsilon`	`1e-06`	`-`	Small numerical protection constant.	Used by: `calculate_soil_surface_resistance` `calculate_optical_properties` `calculate_soil_parameters_pedotransfer` `calculate_soil_conductivity` `calculate_soil_water_potential` `calculate_soil_plant_water_supply` `calculate_soil_hydrology` `calculate_gpp` `calculate_aerodynamic_exchange`
`seconds_per_day`	`86400.0`	`s`	Number of seconds in one day.	Used by: `calculate_soil_plant_water_supply` `calculate_gpp` `calculate_potential_surface_evaporation` `calculate_potential_canopy_liquid_evaporation` `calculate_potential_canopy_transpiration` `calculate_latent_heat_flux` `calculate_soil_hydrology`

physical constants

Name	Value	Units	Description	Relations
`absolute_zero_offset`	`273.15`	`K`	Zero degrees Celsius expressed in Kelvin.	Used by: `calculate_longwave_balance` `calculate_timestep_and_thermodynamics`
`atmospheric_o2`	`209476.0`	`ppm`	Atmospheric O2 mole fraction.	Used by: `calculate_gpp`
`carbon_mass_to_micromole_factor`	`83333.33333333333`	`umol gC-1`	Conversion factor from carbon mass to micromoles of carbon.	Used by: `calculate_gpp`
`co2_michaelis_constant_25`	`404.9`	`ppm`	Rubisco Michaelis constant for CO2 at 25 degrees Celsius.	Used by: `calculate_gpp`
`co2_michaelis_ha`	`79430.0`	`J mol-1`	Activation energy of the Rubisco Michaelis constant for CO2.	Used by: `calculate_gpp`
`freezing_point`	`0.0`	`degC`	Temperature at which water freezes.	Used by: `calculate_precipitation_phase` `calculate_snow_hydrology` `calculate_soil_hydrology`
`gammastar_25`	`42.75`	`ppm`	Photorespiratory CO2 compensation point at 25 degrees Celsius.	Used by: `calculate_gpp`
`gammastar_ha`	`37830.0`	`J mol-1`	Activation energy of the photorespiratory CO2 compensation point.	Used by: `calculate_gpp`
`gb_ratio_co2_to_h2o`	`0.7299270072992701`	`-`	Ratio of CO2 to H2O molecular diffusivity in the leaf boundary layer.	Used by: `calculate_gpp`
`gs_ratio_co2_to_h2o`	`0.625`	`-`	Ratio of CO2 to H2O molecular diffusivity through stomata.	Used by: `calculate_gpp`
`latent_heat_of_sublimation`	`2836000.0`	`J kg-1`	Latent heat of sublimation of water at 0°C.	Used by: `calculate_potential_canopy_sublimation` `calculate_potential_snow_sublimation` `calculate_latent_heat_flux`
`micromole_to_carbon_mass_factor`	`1.2e-05`	`gC umol-1`	Conversion factor from micromoles of carbon to carbon mass.	Used by: `calculate_gpp`
`o2_michaelis_constant_25`	`278400.0`	`ppm`	Rubisco Michaelis constant for O2 at 25 degrees Celsius.	Used by: `calculate_gpp`
`o2_michaelis_ha`	`36380.0`	`J mol-1`	Activation energy of the Rubisco Michaelis constant for O2.	Used by: `calculate_gpp`
`partial_molar_volume_of_water`	`1.805e-05`	`m3 mol-1`	Partial molar volume of water at 20°C.	Used by: `calculate_soil_surface_vapour_gradient`
`specific_heat_capacity_air`	`1004.6`	`J kg-1 K-1`	Specific heat capacity of air.	Used by: `calculate_timestep_and_thermodynamics` `calculate_potential_surface_evaporation` `calculate_potential_canopy_liquid_evaporation` `calculate_potential_canopy_transpiration`
`standard_air_pressure`	`101325.0`	`Pa`	Reference air pressure.	Used by: `calculate_timestep_and_thermodynamics`
`stefan_boltzmann_constant`	`5.670374419e-08`	`W m-2 K-4`	Stefan–Boltzmann constant.	Used by: `calculate_longwave_balance`
`universal_gas_constant`	`8.3144`	`J mol-1 K-1`	Universal gas constant.	Used by: `calculate_timestep_and_thermodynamics` `calculate_soil_surface_vapour_gradient`
`von_karman_constant`	`0.41`	`-`	Von Karman constant.	Used by: `calculate_aerodynamic_exchange`

Errors¶

Residual diagnostics used to check conservation properties and numerical consistency.

See also

See model.variables.errors.

Name	Units	Description	Relations
`canopy_liquid_interception_storage_balance_error`	`mm`	Residual of liquid canopy interception storage balance closure.	Produced by: `calculate_canopy_liquid_hydrology`
`canopy_solid_interception_storage_balance_error`	`mm`	Residual of solid canopy interception storage balance closure.	Produced by: `calculate_canopy_solid_hydrology`
`longwave_balance_error`	`W m-2`	Residual of longwave energy balance closure.	Produced by: `calculate_longwave_balance`
`shortwave_balance_error`	`W m-2`	Residual of shortwave energy balance closure.	Produced by: `calculate_shortwave_balance`
`snow_water_storage_balance_error`	`mm`	Residual of snow water storage balance closure.	Produced by: `calculate_snow_hydrology`
`soil_water_storage_balance_error`	`mm`	Residual of soil water storage balance closure.	Produced by: `calculate_soil_hydrology`