get_Rns_daily: Get net shortwave radiation (Rs)

In gopalpenny/fao56:

Description

Get net shortwave radiation, Rs (FAO 56, Eq. 38) in MJ/m^2/day

Usage

get_Rns_daily(Rs, albedo = 0.23)

Arguments

Rs	downward shortwave radiation, MJ/m^2/day
albedo	albedo or canopy reflectance, unitless

Details

This function calculates net shortwave radiation, in MJ/m^2/day. It uses Eq. 38 from FAO 56 in Chapter 3:

Rns = (1 - albedo) * Rs

Note that for reference ET0, albedo can be taken as 0.23 for hypothetical grass reference crop.

Examples

lat <- -22.9 # Rio de Janeiro
date <- "2019-05-15"
n <- 220 / 31 # 220 hours in a month / 31 days
N <- get_daylight_hours(lat, date)
Ra <- get_Ra_daily(lat, date)
Rs <- get_Rs_daily(Ra, n, N)
Rns <- get_Rns_daily(Rs, albedo = 0.23)

gopalpenny/fao56 documentation built on Feb. 14, 2022, 6:01 a.m.