extrat: Calculate extraterrestrial solar radiation

In sirad: Functions for Calculating Daily Solar Radiation and Evapotranspiration

Description

'extrat' calculates hourly and daily extraterrestrial solar radiation for a given time and location.

Usage

extrat(i, lat)

Arguments

i	day number in the year (julian day)
lat	latitude in radians

Details

Solar radiation outside of the earth's atmosphere is called extraterrestrial solar radiation. It can be calculated based on solar geometry.

Value

List of 3 elements:

ExtraTerrestrialSolarRadiationDaily	daily sum of extraterrestrial radiation [MJm-2]
TerrestrialSolarRadiationHourly	vector of length 24 of hourly sums of extraterrestrial radiation [MJm-2]
DayLength	day length in hours

Author(s)

Jedrzej S. Bojanowski

Examples

## extraterrestrial radiation and daylength for 1 January and latitude 55 degrees
extrat(dayOfYear("2011-01-01"), radians(55))

Example output

$ExtraTerrestrialSolarRadiationDaily
[1] 4.871769

$ExtraTerrestrialSolarRadiationHourly
 [1] 0.0000000 0.0000000 0.0000000 0.0000000 0.0000000 0.0000000 0.0000000
 [8] 0.0000000 0.0000000 0.2698524 0.6964953 0.9646944 1.0561721 0.9646944
[15] 0.6964953 0.2698524 0.0000000 0.0000000 0.0000000 0.0000000 0.0000000
[22] 0.0000000 0.0000000 0.0000000

$DayLength
[1] 7.020899

sirad documentation built on May 1, 2019, 7:42 p.m.