R_nl: Radiation, net longwave

In WDNR-Water-Use/CSLSevap: Evapo(transpi)ration Calculations

Description

Calculates the net outgoing longwave radiation for a given location based on incoming solar radiation, incoming clear-sky radiation, and air temperature records. Based on Equation 39 and p.74-75 in Allen et al. (1998).

Usage

R_nl(dt, Rs, Rso, ea, atmp, SBc = 4.903e-09)

Arguments

dt	string indicating the timestep of input weather series. Expects "hourly", "daily", or "monthly".
Rs	incoming solar radiation (MJ/m^2/timestep), vector or atomic number
Rso	clear-sky solar radiation (MJ/m^2/timestep), vector or atomic number.
ea	actual vapour pressure (kPa), vector or atomic number.
atmp	air temperature (degrees C). When dt is "daily" or larger, argument should be a list with elements "min" and "max" for daily min and max temperatures. When dt is "hourly", argument should be a vector or atomic number with hourly recorded temperatures.
SBc	Stefan-Boltzman constant (MJ/m^2/day). Defaults to 4.903e-9 MJ/m^2/day.

Value

Rnl	Net outgoing longwave radiation (MJ/m^2/hour or MJ/m^2/day, depending on dt)

References

Allen, R. G., Pereira, L. S., Raes, D., & Smith, M. (1998). Crop evapotranspiration: Guidelines for computing crop water requirements. Rome: FAO. Retrieved from http://www.fao.org/docrep/X0490E/x0490e00.htm.

WDNR-Water-Use/CSLSevap documentation built on April 9, 2021, 1:35 a.m.