# Copyright (c) 2008,2015,2016,2018 MetPy Developers. # Distributed under the terms of the BSD 3-Clause License. # SPDX-License-Identifier: BSD-3-Clause # pylint: disable=line-too-long r"""A collection of meteorologically significant constant and thermophysical property values. Earth ----- ======================== =============== =========== ======================================= =============================================================== Name Symbol Short Name Units Description ------------------------ --------------- ----------- --------------------------------------- --------------------------------------------------------------- earth_avg_radius :math:`R_e` Re :math:`\text{m}` Avg. radius of the Earth [1]_ earth_gravity :math:`g` g :math:`\text{m s}^{-2}` Avg. gravity acceleration on Earth [2]_ gravitational_constant :math:`G` G :math:`\text{m}^{3} {kg}^{-1} {s}^{-2}` Gravitational constant [2]_ earth_avg_angular_vel :math:`\Omega` omega :math:`\text{rad s}^{-1}` Avg. angular velocity of Earth [1]_ earth_sfc_avg_dist_sun :math:`d` d :math:`\text{m}` Avg. distance of the Earth from the Sun [3]_ earth_solar_irradiance :math:`S` S :math:`\text{W m}^{-2}` Avg. solar irradiance of Earth [4]_ earth_max_declination :math:`\delta` delta :math:`\text{degrees}` Max. solar declination angle of Earth earth_orbit_eccentricity :math:`e` :math:`\text{None}` Avg. eccentricity of Earth's orbit earth_mass :math:`m_e` me :math:`\text{kg}` Total mass of the Earth (approx) [1]_ [2]_ ======================== =============== =========== ======================================= =============================================================== Water ----- ======================= ================ ========== ============================ ==================================================== Name Symbol Short Name Units Description ----------------------- ---------------- ---------- ---------------------------- ---------------------------------------------------- water_molecular_weight :math:`M_w` Mw :math:`\text{g mol}^{-1}` Molecular weight of water [5]_ water_gas_constant :math:`R_v` Rv :math:`\text{J (K kg)}^{-1}` Gas constant for water vapor [2]_ [5]_ density_water :math:`\rho_l` rho_l :math:`\text{kg m}^{-3}` Maximum recommended density of liquid water, 0-40C [5]_ wv_specific_heat_press :math:`C_{pv}` Cp_v :math:`\text{J (K kg)}^{-1}` Specific heat at constant pressure for water vapor wv_specific_heat_vol :math:`C_{vv}` Cv_v :math:`\text{J (K kg)}^{-1}` Specific heat at constant volume for water vapor water_specific_heat :math:`Cp_l` Cp_l :math:`\text{J (K kg)}^{-1}` Specific heat of liquid water at 0C [6]_ water_heat_vaporization :math:`L_v` Lv :math:`\text{J kg}^{-1}` Latent heat of vaporization for liquid water at 0C [7]_ water_heat_fusion :math:`L_f` Lf :math:`\text{J kg}^{-1}` Latent heat of fusion for liquid water at 0C [7]_ ice_specific_heat :math:`C_{pi}` Cp_i :math:`\text{J (K kg)}^{-1}` Specific heat of ice at 0C [7]_ density_ice :math:`\rho_i` rho_i :math:`\text{kg m}^{-3}` Density of ice at 0C ======================= ================ ========== ============================ ==================================================== Dry Air ------- ======================== ================ ============= ============================ ==================================================================== Name Symbol Short Name Units Description ------------------------ ---------------- ------------- ---------------------------- -------------------------------------------------------------------- dry_air_molecular_weight :math:`M_d` Md :math:`\text{g / mol}` Nominal molecular weight of dry air at the surface of th Earth [8]_ dry_air_gas_constant :math:`R_d` Rd :math:`\text{J (K kg)}^{-1}` Gas constant for dry air at the surface of the Earth dry_air_spec_heat_press :math:`C_{pd}` Cp_d :math:`\text{J (K kg)}^{-1}` Specific heat at constant pressure for dry air dry_air_spec_heat_vol :math:`C_{vd}` Cv_d :math:`\text{J (K kg)}^{-1}` Specific heat at constant volume for dry air dry_air_density_stp :math:`\rho_d` rho_d :math:`\text{kg m}^{-3}` Density of dry air at 0C and 1000mb ======================== ================ ============= ============================ ==================================================================== General Meteorology Constants ----------------------------- ======================== ================= =========== ========================= ======================================================= Name Symbol Short Name Units Description ------------------------ ----------------- ----------- ------------------------- ------------------------------------------------------- pot_temp_ref_press :math:`P_0` P0 :math:`\text{Pa}` Reference pressure for potential temperature poisson_exponent :math:`\kappa` kappa :math:`\text{None}` Exponent in Poisson's equation (Rd/Cp_d) dry_adiabatic_lapse_rate :math:`\gamma_d` gamma_d :math:`\text{K km}^{-1}` The dry adiabatic lapse rate molecular_weight_ratio :math:`\epsilon` epsilon :math:`\text{None}` Ratio of molecular weight of water to that of dry air ======================== ================= =========== ========================= ======================================================= .. [1] [Moritz2000]_ .. [2] [CODATA2018]_ .. [3] [IAU2012]_ .. [4] [Kopp2011]_ .. [5] [IAPWS2001]_ .. [6] [IAPWS1995]_ .. [7] [WMO1966]_ .. [8] [Picard2008]_ """ # noqa: E501 # pylint: enable=line-too-long # pylint: disable=invalid-name # Earth earth_gravity = g = 9.80665 # 'm / s^2' Re = earth_avg_radius = 6371008.7714 # 'm' G = gravitational_constant = 6.67430e-11 # 'm^3 / kg / s^2' GM = geocentric_gravitational_constant = 3986005e8 # 'm^3 / s^2' omega = earth_avg_angular_vel = 7292115e-11 # 'rad / s' d = earth_sfc_avg_dist_sun = 149597870700.0 # 'm' S = earth_solar_irradiance = 1360.8 # 'W / m^2' delta = earth_max_declination = 23.45 # 'degrees' earth_orbit_eccentricity = 0.0167 # 'dimensionless' earth_mass = me = geocentric_gravitational_constant / gravitational_constant # molar gas constant R = 8.314462618 # 'J / mol / K' # Water Mw = water_molecular_weight = 18.015268 # 'g / mol' Rv = water_gas_constant = R / Mw rho_l = density_water = 999.97495 # 'kg / m^3' wv_specific_heat_ratio = 1.330 # 'dimensionless' Cp_v = wv_specific_heat_press = ( wv_specific_heat_ratio * Rv / (wv_specific_heat_ratio - 1) ) Cv_v = wv_specific_heat_vol = Cp_v / wv_specific_heat_ratio Cp_l = water_specific_heat = 4.2194 # 'kJ / kg / K' Lv = water_heat_vaporization = 2.50084e6 # 'J / kg' Lf = water_heat_fusion = 3.337e5 # 'J / kg' Cp_i = ice_specific_heat = 2090 # 'J / kg / K' rho_i = density_ice = 917 # 'kg / m^3' # Dry air Md = dry_air_molecular_weight = 28.96546e-3 # 'kg / mol' Rd = dry_air_gas_constant = R / Md dry_air_spec_heat_ratio = 1.4 # 'dimensionless' Cp_d = dry_air_spec_heat_press = ( dry_air_spec_heat_ratio * Rd / (dry_air_spec_heat_ratio - 1) ) Cv_d = dry_air_spec_heat_vol = Cp_d / dry_air_spec_heat_ratio # TODO : check unit conversion # rho_d = dry_air_density_stp = (1000., 'mbar') / (Rd * 273.15, 'K'))) # 'kg / m^3' # General meteorology constants P0 = pot_temp_ref_press = 1000.0 # 'mbar' # TODO : check unit conversion kappa = poisson_exponent = Rd / Cp_d # 'dimensionless' gamma_d = dry_adiabatic_lapse_rate = g / Cp_d # TODO : check unit conversion epsilon = molecular_weight_ratio = Mw / Md # 'dimensionless'