aiRthermoConstants {aiRthermo} | R Documentation |

## Thermodynamical Constansts

### Description

Frecuently used constants in atmospheric thermodynamics and in this package.

### Usage

`data(aiRthermoConstants)`

### Format

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

### Details

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).

### References

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.

### Examples

```
#Define the Rd
data(aiRthermoConstants)
Rd <- aiRthermoConstants['Rd']
#Define gravity
data(aiRthermoConstants)
g <- aiRthermoConstants['g']
```

*aiRthermo*version 1.2.1 Index]