aiRthermoConstants {aiRthermo}R Documentation

Thermodynamical Constansts


Frecuently used constants in atmospheric thermodynamics and in this package.




aiRthermoConstants is a vector that includes the constants used by many of the functions in package.


The constants stored in the vector are (in SI units): the gas constant for dry air R_d and for water vapour R_v (\frac{J}{Kkg}), the temperature T_0 corresponding to 0 degree Celsius, es_0 used to calculate the saturated vapour pressure (Pa), 1000 hPa in Pa (P1000), the specific heat of dry air for constant pressure c_p (\frac{J}{Kkg}) and for constant volume c_v (\frac{J}{Kkg}), acceleration due to gravity at sea level g (\frac{m}{s^2}), our definition of a missing value MISSING_VALUE (-99999999) and epsilon \varepsilon (\frac{R_d}{R_v}).

The values of the constants are taken from Bohren & Albrecht (1998), and they are also consistent with those used in Petty (2008), Erukhimova & North (2009) and Davies-Jones (2009).


Bohren, C.F., & Albrecht, B. A. (1998). Atmospheric thermodynamics. Atmospheric thermodynamics. Publisher: New York; Oxford: Oxford University Press, 1998. ISBN: 0195099044.

Petty, G.W. (2008). A First Course in Atmospheric Thermodynamics, Sundog Publishing, Madison.

North, G. R. , Erukhimova,T. L. (2009). Atmospheric Thermodynamics, Cambridge University Press, New York.

Davies-Jones, R. (2009). On formulas for equivalent potential temperature, Monthly Weather Review, 137,3137-3148. doi:10.1175/2009MWR2774.1.


#Define the Rd
Rd <- aiRthermoConstants['Rd']

#Define gravity
g <- aiRthermoConstants['g'] 

[Package aiRthermo version 1.2.1 Index]