potentialEvaporation: Potential evaporation

In environmentalinformatics-marburg/reset: Remote Sensing-Based Evapotranspiration

Description

Calculate the potential evaporation. Currently available equations include Priestley and Taylor (1972).

Usage

potentialEvaporation(Rn, G, delta, gamma, alpha = 1.26)

Arguments

Rn	numeric or Raster* object, net radiation (MJ m-2 day-1).
G	numeric or Raster* object, soil heat flux (MJ m-2 day-1).
delta	numeric or Raster* object, slope of the saturation vapor pressure curve (kPa / deg C) at air temperature, e.g. derived from vaporPressureSat.
gamma	numeric or Raster* object, psychrometric constant (kPa / deg C), e.g. derived from psychrometricConstant.
alpha	numeric, Priestley-Taylor constant, defaults to 1.26 for advection-free saturated surfaces (see References).

Value

If any of the inputs is a Raster* object, a Raster* object; else a numeric object (in mm per logging interval).

References

McMahon TA, Peel MC, Lowe L, Srikanthan R, McVicar TR (2013) Estimating actual, potential, reference crop and pan evaporation using standard meteorological data: a pragmatic synthesis. Hydrology and Earth System Sciences 17, 1331-1363, doi:10.5194/hess-17-1331-2013.

Priestley CHB, Taylor RJ (1972) On the assessment of surface heat flux and evaporation using large scale parameters. Monthly Weather Reviews 100, 81-92, doi:10.1175/1520-0493(1972)100<0081:OTAOSH>2.3.CO;2.

See Also

vaporPressureSat, psychrometricConstant.

environmentalinformatics-marburg/reset documentation built on May 16, 2019, 7:54 a.m.