climt.EmanuelConvection

class climt.EmanuelConvection(minimum_convecting_layer=1, autoconversion_water_content_threshold=0.0011, autoconversion_temperature_threshold=-55, entrainment_mixing_coefficient=1.5, downdraft_area_fraction=0.05, precipitation_fraction_outside_cloud=0.12, speed_water_droplets=50.0, speed_snow=5.5, rain_evaporation_coefficient=1.0, snow_evaporation_coefficient=0.8, convective_momentum_transfer_coefficient=0.7, downdraft_surface_velocity_coefficient=10.0, convection_bouyancy_threshold=0.9, mass_flux_relaxation_rate=0.1, mass_flux_damping_rate=0.1, reference_mass_flux_timescale=300.0, **kwargs)

The Emanuel convection scheme from [Emanuel and Zivkovic-Rothman]

__init__(minimum_convecting_layer=1, autoconversion_water_content_threshold=0.0011, autoconversion_temperature_threshold=-55, entrainment_mixing_coefficient=1.5, downdraft_area_fraction=0.05, precipitation_fraction_outside_cloud=0.12, speed_water_droplets=50.0, speed_snow=5.5, rain_evaporation_coefficient=1.0, snow_evaporation_coefficient=0.8, convective_momentum_transfer_coefficient=0.7, downdraft_surface_velocity_coefficient=10.0, convection_bouyancy_threshold=0.9, mass_flux_relaxation_rate=0.1, mass_flux_damping_rate=0.1, reference_mass_flux_timescale=300.0, **kwargs)

Parameters:

• minimum_convecting_layer (int, optional) – The least model level from which convection can be initiated. Normally set to 1 if using bulk PBL schemes. Else, it should be set to the first model level at which the temperature is defined.
• autoconversion_water_content_threshold (float, optional) – The amount of water vapour in \(kg/kg\) above which condensation occurs in warm (above freezing point of water) clouds. This value linearly reduces to zero between the freezing point and the autoconversion_temperature_threshold.
• autoconversion_temperature_threshold (float, optional) – The temperature in \(^\circ C\) below which all water vapour is converted to rain/snow.
• entrainment_mixing_coefficient (float, optional) – The coefficient of mixing for entrainment of environmental air into the cloud.
• downdraft_area_fraction (float, optional) – The fractional area covered by unsaturated downdrafts.
• precipitation_fraction_outside_cloud (float, optional) – The fraction of precipitation falling outside the cloud.
• speed_water_droplets (float, optional) – The speed of descent of water droplets in \(Pa/s\).
• speed_snow (float, optional) – The speed of descent of snow in \(Pa/s\).
• rain_evaporation_coefficient (float, optional) – Coefficient governing the rate of evaporation of rain.
• snow_evaporation_coefficient (float, optional) – Coefficient governing the rate of evaporation of snow.
• convective_momentum_transfer_coefficient (float, optional) – Coefficient between 0 and 1 governing momentum transport by clouds. A value of 1 shuts off momentum transport.
• downdraft_surface_velocity_coefficient (float, optional) – Coefficient mulitplying the downdraft mass flux to calculate the downdraft velocity scale.
• convection_bouyancy_threshold (float, optional) – The maximum negative temperature perturbation in \(degK\) a parcel can have below the temperature at its level of free convection. If difference is greater, and previous cloud base mass flux is zero, there is no convection.
• mass_flux_relaxation_rate (float, optional) – Coefficient governing the rate of relaxation to subcloud-layer quasi-equilibrium.
• mass_flux_damping_rate (float, optional) – Coefficient which damps the currently calculated mass flux towards the value from the previous time step.
• reference_mass_flux_timescale (float, optional) – Timescale used to calculate the actual damping coefficient along with mass_flux_damping_rate and the current time step.

Methods

__init__([minimum_convecting_layer, …])	param minimum_convecting_layer:  The least model level from which convection can be initiated. Normally set
array_call(raw_state, timestep)	Get convective heating and moistening.

Attributes

diagnostic_properties
input_properties
name
tendencies_in_diagnostics
tendency_properties
tracer_tendency_time_unit
uses_tracers