API for the constants module
The models.abiotic.constants module contains a set of dataclasses which contain
parameters required by the broader
abiotic_model model.
These parameters are constants in that they should not be changed during a particular
simulation.
Classes:
|
Dataclass to store all constants for the abiotic model. |
- class virtual_ecosystem.models.abiotic.constants.AbioticConsts(wind_reference_height: float = 10.0, specific_heat_equ_factors: list[float] = <factory>, latent_heat_vap_equ_factors: list[float] = <factory>, zero_plane_scaling_parameter: float = 7.5, substrate_surface_drag_coefficient: float = 0.003, roughness_element_drag_coefficient: float = 0.3, roughness_sublayer_depth_parameter: float = 0.193, max_ratio_wind_to_friction_velocity: float = 0.3, drag_coefficient: float = 0.2, relative_turbulence_intensity: float = 0.5, diabatic_correction_factor_below: float = 1, mixing_length_factor: float = 0.32, min_relative_turbulence_intensity: float = 0.36, max_relative_turbulence_intensity: float = 0.9, min_wind_speed_above_canopy: float = 0.1, min_windspeed_below_canopy: float = 0.001, min_friction_velocity: float = 0.001, min_roughness_length: float = 0.01, yasuda_stability_parameters: list[float] = <factory>, diabatic_heat_momentum_ratio: float = 0.6, turbulence_sign: bool = True, canopy_temperature_ini_factor: float = 0.01, light_extinction_coefficient: float = 0.01, gas_constant_water_vapour: float = 461.51, specific_heat_capacity_leaf: float = 2760.0, leaf_heat_transfer_coefficient: float = 50.0, stomatal_resistance: float = 200.0, soil_thermal_conductivity: float = 0.7, specific_heat_capacity_soil: float = 2700000.0, initial_air_conductivity: float = 50.0, top_leaf_vapour_conductivity: float = 0.32, bottom_leaf_vapour_conductivity: float = 0.25, top_leaf_air_conductivity: float = 0.19, bottom_leaf_air_conductivity: float = 0.13, surface_albedo: float = 0.125, soil_emissivity: float = 0.8, surface_layer_depth: float = 0.1, volume_to_weight_conversion: float = 1000.0, kinematic_viscosity_parameters: list[float] = <factory>, thermal_diffusivity_parameters: list[float] = <factory>, grashof_parameter: float = 9.807, forced_conductance_parameter: float = 0.34, positive_free_conductance_parameter: float = 0.54, negative_free_conductance_parameter: float = 0.26, leaf_emissivity: float = 0.8, saturated_pressure_slope_parameters: list[float] = <factory>, wind_profile_parameters: list[float] = <factory>, richardson_bounds: list[float] = <factory>, stable_wind_shear_slope: float = 4.7, stable_temperature_gradient_intercept: float = 0.74)
Dataclass to store all constants for the abiotic model.
Methods:
__init__([wind_reference_height, ...])Attributes:
Initial leaf air heat conductivity at the bottom of the canopy, [mol m-2 s-1].
Initial leaf vapour conductivity at the bottom of the canopy, [mol m-2 s-1].
Factor used to initialise canopy temperature as a function of air temperature and absorbed shortwave radiation.
Diabatic correction factor below canopy, dimensionless.
Factor that relates diabatic correction factors for heat and momentum.
Drag coefficient, dimensionless.
Parameter in calculation of forced conductance (Campbell and Norman, 2012).
Gas constant for water vapour, [J kg -1 K-1].
Parameter in calculation of Grashof number (Campbell and Norman, 2012).
Initial air conductivity, [mol m-2 s-1].
Parameters in calculation of kinematic viscosity (Campbell and Norman, 2012).
Factors in calculation of latent heat of vapourisation.
Leaf emissivity, dimensionless.
Leaf heat transfer coefficient, [s^1/2 m^-1/2], (Linacre, 1964).
Light extinction coefficient for canopy.
Maximum ratio of wind velocity to friction velocity, dimensionless.
Maximum relative turbulence intensity, dimensionless.
Minimum friction velocity, [m s-1].
Minimum relative turbulence intensity, dimensionless.
Minimum roughness length, [m].
Minimum wind speed above the canopy, [m s-1].
Minimum wind speed below the canopy or in absence of vegetation, [m s-1].
Factor in calculation of mixing length, dimensionless.
Parameter in calculation of free conductance for negative temperature difference (Campbell and Norman, 2012).
Parameter in calculation of free conductance for positive temperature difference (Campbell and Norman, 2012).
Relative turbulence intensity, dimensionless.
Minimum and maximum value for Richardson number.
Roughness-element drag coefficient, dimensionless.
Parameter characterizes the roughness sublayer depth.
List of parameters to calcualte the slope of saturated vapour pressure curve.
Soil emissivity, dimensionless.
Soil thermal conductivity, [W m-1 K-1], (Monteith and Unsworth, 1990).
Specific heat capacity of leaf, [J kg-1 K-1], (Aston, 1985).
Specific heat capacity of soil, [J kg-1 K-1], (Monteith and Unsworth, 1990).
Factors in calculation of molar specific heat of air.
Temperature gradient intercept under stable conditions after Goudriaan (1977).
Wind shear slope under stable conditions after Gourdiaan (1977).
Default stomatal resistance, [s m2 mumol-1].
Substrate-surface drag coefficient, dimensionless.
Mean surface albedo of a tropical rainforest in South East Asia, dimensionless.
Surface layer depth, [m].
Parameter in calculation of thermal diffusivity (Campbell and Norman, 2012).
Initial leaf air heat conductivity at the top of the canopy, [mol m-2 s-1].
Initial leaf vapour conductivity at the top of the canopy, [mol m-2 s-1].
Flag indicating if turbulence increases or decreases with height.
Factor to convert between soil volume and weight in kilograms.
Factors in calculation of logarithmic wind profile above canopy.
Reference height for wind speed above the canopy.
Parameters to approximate diabatic correction factors for heat and momentum.
Control parameter for scaling zero displacement to height, dimensionless.
- __init__(wind_reference_height: float = 10.0, specific_heat_equ_factors: list[float] = <factory>, latent_heat_vap_equ_factors: list[float] = <factory>, zero_plane_scaling_parameter: float = 7.5, substrate_surface_drag_coefficient: float = 0.003, roughness_element_drag_coefficient: float = 0.3, roughness_sublayer_depth_parameter: float = 0.193, max_ratio_wind_to_friction_velocity: float = 0.3, drag_coefficient: float = 0.2, relative_turbulence_intensity: float = 0.5, diabatic_correction_factor_below: float = 1, mixing_length_factor: float = 0.32, min_relative_turbulence_intensity: float = 0.36, max_relative_turbulence_intensity: float = 0.9, min_wind_speed_above_canopy: float = 0.1, min_windspeed_below_canopy: float = 0.001, min_friction_velocity: float = 0.001, min_roughness_length: float = 0.01, yasuda_stability_parameters: list[float] = <factory>, diabatic_heat_momentum_ratio: float = 0.6, turbulence_sign: bool = True, canopy_temperature_ini_factor: float = 0.01, light_extinction_coefficient: float = 0.01, gas_constant_water_vapour: float = 461.51, specific_heat_capacity_leaf: float = 2760.0, leaf_heat_transfer_coefficient: float = 50.0, stomatal_resistance: float = 200.0, soil_thermal_conductivity: float = 0.7, specific_heat_capacity_soil: float = 2700000.0, initial_air_conductivity: float = 50.0, top_leaf_vapour_conductivity: float = 0.32, bottom_leaf_vapour_conductivity: float = 0.25, top_leaf_air_conductivity: float = 0.19, bottom_leaf_air_conductivity: float = 0.13, surface_albedo: float = 0.125, soil_emissivity: float = 0.8, surface_layer_depth: float = 0.1, volume_to_weight_conversion: float = 1000.0, kinematic_viscosity_parameters: list[float] = <factory>, thermal_diffusivity_parameters: list[float] = <factory>, grashof_parameter: float = 9.807, forced_conductance_parameter: float = 0.34, positive_free_conductance_parameter: float = 0.54, negative_free_conductance_parameter: float = 0.26, leaf_emissivity: float = 0.8, saturated_pressure_slope_parameters: list[float] = <factory>, wind_profile_parameters: list[float] = <factory>, richardson_bounds: list[float] = <factory>, stable_wind_shear_slope: float = 4.7, stable_temperature_gradient_intercept: float = 0.74) None
- bottom_leaf_air_conductivity: float = 0.13
Initial leaf air heat conductivity at the bottom of the canopy, [mol m-2 s-1].
- bottom_leaf_vapour_conductivity: float = 0.25
Initial leaf vapour conductivity at the bottom of the canopy, [mol m-2 s-1].
- canopy_temperature_ini_factor: float = 0.01
Factor used to initialise canopy temperature as a function of air temperature and absorbed shortwave radiation.
- diabatic_correction_factor_below: float = 1
Diabatic correction factor below canopy, dimensionless.
The diabatic correction factor is a scaling adjustment used to compensate for the effects of vertical heat transfer or thermal non-adiabaticity on atmospheric variables or processes, particularly when estimating or interpreting measurements across different heights or conditions. This factor is used to adjust wind profiles below the canopy. Implementation and value from Maclean and Klinges (2021).
- diabatic_heat_momentum_ratio: float = 0.6
Factor that relates diabatic correction factors for heat and momentum.
Dimenionless parameter, implementation after Maclean and Klinges (2021) and values taken from Yasuda (1988).
- drag_coefficient: float = 0.2
Drag coefficient, dimensionless.
The drag coefficient is a dimensionless quantity that characterizes the drag or resistance experienced by an object moving through a fluid (here the atmosphere) and is defined as the ratio of the drag force on the object to the dynamic pressure of the fluid flow and the reference area of the object. Implementation and value from Maclean and Klinges (2021).
- forced_conductance_parameter: float = 0.34
Parameter in calculation of forced conductance (Campbell and Norman, 2012).
- grashof_parameter: float = 9.807
Parameter in calculation of Grashof number (Campbell and Norman, 2012).
- kinematic_viscosity_parameters: list[float]
Parameters in calculation of kinematic viscosity (Campbell and Norman, 2012).
- latent_heat_vap_equ_factors: list[float]
Factors in calculation of latent heat of vapourisation.
Implementation after Maclean and Klinges (2021), value is taken from Henderson-Sellers (1984).
- leaf_heat_transfer_coefficient: float = 50.0
Leaf heat transfer coefficient, [s^1/2 m^-1/2], (Linacre, 1964).
- max_ratio_wind_to_friction_velocity: float = 0.3
Maximum ratio of wind velocity to friction velocity, dimensionless.
Implementation and value from Maclean and Klinges (2021).
- max_relative_turbulence_intensity: float = 0.9
Maximum relative turbulence intensity, dimensionless.
See
relative_turbulence_intensity. The default value from Shaw et al (1974) Agricultural Meteorology, 13: 419-425. TODO this is not representative of a rainforest environment and needs to be adjusted.
- min_relative_turbulence_intensity: float = 0.36
Minimum relative turbulence intensity, dimensionless.
See
relative_turbulence_intensity. The default value is taken from Shaw et al (1974) Agricultural Meteorology, 13: 419-425. TODO this is not representative of a rainforest environment and needs to be adjusted.
- min_roughness_length: float = 0.01
Minimum roughness length, [m].
The minimum roughness length represents the lowest height at which the surface roughness significantly affects the wind flow over a particular terrain or surface. Implementation and value from Maclean and Klinges (2021).
- min_wind_speed_above_canopy: float = 0.1
Minimum wind speed above the canopy, [m s-1].
Implementation and value from Maclean and Klinges (2021).
- min_windspeed_below_canopy: float = 0.001
Minimum wind speed below the canopy or in absence of vegetation, [m s-1].
- mixing_length_factor: float = 0.32
Factor in calculation of mixing length, dimensionless.
Implementation and value from Maclean and Klinges (2021).
- negative_free_conductance_parameter: float = 0.26
Parameter in calculation of free conductance for negative temperature difference (Campbell and Norman, 2012).
- positive_free_conductance_parameter: float = 0.54
Parameter in calculation of free conductance for positive temperature difference (Campbell and Norman, 2012).
- relative_turbulence_intensity: float = 0.5
Relative turbulence intensity, dimensionless.
The relative turbulence intensity is a proportionality factor that relates the mean eddy velocity is assumed to the local wind speed below the canopy. Implementation and value from Maclean and Klinges (2021).
- roughness_element_drag_coefficient: float = 0.3
Roughness-element drag coefficient, dimensionless.
The roughness-element drag coefficient refers to the dimensionless coefficient used to quantify the drag force exerted by individual roughness elements (such as buildings, trees, or surface irregularities) on airflow, influencing the overall aerodynamic characteristics of a surface within the atmospheric boundary layer. Implementation and value from Maclean and Klinges (2021).
- roughness_sublayer_depth_parameter: float = 0.193
Parameter characterizes the roughness sublayer depth.
The roughness sublayer depth refers to the layer near the surface where the effects of surface roughness significantly influence airflow, turbulence, and momentum transfer, typically extending up to about 10% of the height of the roughness elements or features on the surface. This layer is characterized by intense turbulence and rapid velocity changes due to surface irregularities. Implentation and value taken from (Maclean and Klinges, 2021).
- saturated_pressure_slope_parameters: list[float]
List of parameters to calcualte the slope of saturated vapour pressure curve.
- soil_thermal_conductivity: float = 0.7
Soil thermal conductivity, [W m-1 K-1], (Monteith and Unsworth, 1990).
- specific_heat_capacity_leaf: float = 2760.0
Specific heat capacity of leaf, [J kg-1 K-1], (Aston, 1985).
- specific_heat_capacity_soil: float = 2700000.0
Specific heat capacity of soil, [J kg-1 K-1], (Monteith and Unsworth, 1990).
- specific_heat_equ_factors: list[float]
Factors in calculation of molar specific heat of air.
Implementation after Maclean and Klinges (2021).
- stable_temperature_gradient_intercept: float = 0.74
Temperature gradient intercept under stable conditions after Goudriaan (1977).
- stable_wind_shear_slope: float = 4.7
Wind shear slope under stable conditions after Gourdiaan (1977).
- substrate_surface_drag_coefficient: float = 0.003
Substrate-surface drag coefficient, dimensionless.
The substrate-surface drag coefficient represents the resistance encountered by an object moving on or through a surface and varies based on the nature of the surface and the object’s properties. Here, it affects how wind speed is altered by a surface . Implementation and value from Maclean and Klinges (2021).
- surface_albedo: float = 0.125
Mean surface albedo of a tropical rainforest in South East Asia, dimensionless.
The value is takes from a study that compares changes in surface albedo before and after deforestation in South East Asia (Wilson, 2020).
- surface_layer_depth: float = 0.1
Surface layer depth, [m].
This depth defines the soil depth that is directly involved in the surface energy balance.
- thermal_diffusivity_parameters: list[float]
Parameter in calculation of thermal diffusivity (Campbell and Norman, 2012).
- top_leaf_air_conductivity: float = 0.19
Initial leaf air heat conductivity at the top of the canopy, [mol m-2 s-1].
- top_leaf_vapour_conductivity: float = 0.32
Initial leaf vapour conductivity at the top of the canopy, [mol m-2 s-1].
- volume_to_weight_conversion: float = 1000.0
Factor to convert between soil volume and weight in kilograms.
- wind_profile_parameters: list[float]
Factors in calculation of logarithmic wind profile above canopy.
- wind_reference_height: float = 10.0
Reference height for wind speed above the canopy. The reference height for horizontal wind is typically 10m above ground compared to 2m for other atmospheric variables such as temperature and relative humidity. We assume here that the reference height is above the canopy, please check the input data carefully and be aware of limitations.