utils: Physical utility functions

Description

Set of functions used in the calculation of physical variables.

Usage

utils_airDensity(temperature, Patm)
utils_atmosphericPressure(elevation)
utils_averageDailyVP(Tmin, Tmax, RHmin, RHmax)
utils_averageDaylightTemperature(Tmin, Tmax)
utils_latentHeatVaporisation(temperature)
utils_latentHeatVaporisationMol(temperature)
utils_psychrometricConstant(temperature, Patm)
utils_saturationVP(temperature)
utils_saturationVaporPressureCurveSlope(temperature)

Value

Values returned for each function are:

utils_airDensity: air density (in kg·m-3).
utils_atmosphericPressure: Air atmospheric pressure (in kPa).
utils_averageDailyVP: average (actual) vapour pressure (in kPa).
utils_averageDaylightTemperature: average daylight air temperature (in ºC).
utils_latentHeatVaporisation: Latent heat of vaporisation (MJ·kg-1).
utils_latentHeatVaporisationMol: Latent heat of vaporisation (J·mol-1).
utils_psychrometricConstant: Psychrometric constant (kPa·ºC-1).
utils_saturationVP: saturation vapour pressure (in kPa).
utils_saturationVaporPressureCurveSlope: Slope of the saturation vapor pressure curve (kPa·ºC-1).

Arguments

temperature: Air temperature (ºC).
Tmin, Tmax: Minimum and maximum daily temperature (ºC).
RHmin, RHmax: Minimum and maximum relative humidity (%).
Patm: Atmospheric air pressure (in kPa).
elevation: Elevation above sea level (in m).

Author

Miquel De Cáceres Ainsa, CREAF

References

McMurtrie, R. E., D. A. Rook, and F. M. Kelliher. 1990. Modelling the yield of Pinus radiata on a site limited by water and nitrogen. Forest Ecology and Management 30:381–413.

McMahon, T. A., M. C. Peel, L. Lowe, R. Srikanthan, and T. R. McVicar. 2013. Estimating actual, potential, reference crop and pan evaporation using standard meteorological data: a pragmatic synthesis. Hydrology & Earth System Sciences 17:1331–1363. See also: http://www.fao.org/docrep/x0490e/x0490e06.htm