4.7.1.4. meteo_si.humidity

4.7.1.4.1. Module Contents

4.7.1.4.1.1. Functions

a2e(a, T)

Calculate water vapor pressure from the absolute humidity and air

e2a(e, T)

Calculate the absolute humidity from water vapor pressure and air

e_sat_gg_water(T)

Calculates the saturation pressure over water after "Guide to

e_sat_gg_ice(T)

Calculates the saturation pressure over water after "Guide to

e2q(e, p)

Calculate the specific humidity from vapor pressure and air

q2e(q, p)

Calculate water vapor pressure from the specific humidity and air

rh2q(rh, T, p, e_sat_func=e_sat_gg_water)

Calculate the specific humidity from relative humidity, air temperature,

rh2a(rh, T, e_sat_func=e_sat_gg_water)

Calculate the absolute humidity from relative humidity, air temperature,

a2rh(a, T, e_sat_func=e_sat_gg_water)

Calculate the absolute humidity from relative humidity, air temperature,

q2rh(q, T, p, e_sat_func=e_sat_gg_water)

Calculate relative humidity from specific humidity. Source: Kraus, 'Die

rh_to_iwv(relhum_lev, temp_lev, press_lev, hgt_lev)

Integrate relative humidity to obtain the integrated water vapor (IWV)
a2e(a, T)[source]

Calculate water vapor pressure from the absolute humidity and air temperature.

Parameters

  • a – absolute humidity [kg / m3]

  • T – Temperature in K

Returns

vapor pressure [Pa]

Return type

float

e2a(e, T)[source]

Calculate the absolute humidity from water vapor pressure and air temperature.

Parameters

  • e – vapor pressure [Pa]

  • T – Temperature in K

Returns

absolute humidity [kg / m3]

Return type

float

e_sat_gg_water(T)[source]

Calculates the saturation pressure over water after “Guide to Meteorological Instruments and Methods of Observation” (CIMO Guide) (WMO, 2008).

Parameters

T – Temperature in K

Returns

saturation pressure [Pa]

Return type

float

e_sat_gg_ice(T)[source]

Calculates the saturation pressure over water after “Guide to Meteorological Instruments and Methods of Observation” (CIMO Guide) (WMO, 2008).

Parameters

T – Temperature in K

Returns

saturation pressure [Pa]

Return type

float

e2q(e, p)[source]

Calculate the specific humidity from vapor pressure and air pressure.

Parameters

  • e – vapor pressure [Pa]

  • p – pressure [Pa]

Returns

specific humidity [kg / kg]

Return type

float

q2e(q, p)[source]

Calculate water vapor pressure from the specific humidity and air pressure.

Parameters

  • q – specific humidity [kg / kg]

  • p – pressure [Pa]

Returns

vapor pressure [Pa]

Return type

float

rh2q(rh, T, p, e_sat_func=e_sat_gg_water)[source]

Calculate the specific humidity from relative humidity, air temperature, and pressure.

Parameters

  • rh – Relative humidity in Pa / Pa

  • T – Temperature in K

  • p – pressure [Pa]

  • e_sat_func (func, optional) – Function to estimate the saturation pressure. E.g. e_sat_gg_water for water and e_sat_gg_ice for ice.

Returns

specific humidity [kg / kg]

Return type

float

rh2a(rh, T, e_sat_func=e_sat_gg_water)[source]

Calculate the absolute humidity from relative humidity, air temperature, and pressure.

Parameters

  • rh – Relative humidity in Pa / Pa

  • T – Temperature in K

  • e_sat_func (func, optional) – Function to estimate the saturation pressure. E.g. e_sat_gg_water for water and e_sat_gg_ice for ice.

Returns

absolute humidity [kg / m3]

Return type

float

a2rh(a, T, e_sat_func=e_sat_gg_water)[source]

Calculate the absolute humidity from relative humidity, air temperature, and pressure. Source: Kraus, ‘Die Atmosphäre der Erde’, Chapter 8.1.2

Parameters

  • a – absolute humidity [kg / m3]

  • T – Temperature in K

  • e_sat_func (func, optional) – Function to estimate the saturation pressure. E.g. e_sat_gg_water for water and e_sat_gg_ice for ice.

Returns

relative humidity [kg / kg]

Return type

float

q2rh(q, T, p, e_sat_func=e_sat_gg_water)[source]

Calculate relative humidity from specific humidity. Source: Kraus, ‘Die Atmosphäre der Erde’, Chapter 8.1.2

Parameters

  • q – specific humidity [kg / kg]

  • T – Temperature in K

  • p – pressure [Pa]

  • e_sat_func (func, optional) – Function to estimate the saturation pressure. E.g. e_sat_gg_water for water and e_sat_gg_ice for ice.

Returns

relative humidity [kg / kg]

Return type

float

rh_to_iwv(relhum_lev, temp_lev, press_lev, hgt_lev)[source]

Integrate relative humidity to obtain the integrated water vapor (IWV) column.

Parameters

  • relhum_lev – relative humidity at levels humidity [Pa / Pa]

  • temp_lev – Temperature at levels [K]

  • press_lev – pressure at levels [Pa]

  • hgt_levels – altitude of levels [m]

Returns

IWV [kg / m^2]

Return type

float