sirad (version 2.3-1)

extrat: Calculate extraterrestrial solar radiation

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

Value

List of 3 elements:

ExtraTerrestrialSolarRadiationDaily

daily sum of extraterrestrial radiation

TerrestrialSolarRadiationHourly

vector of length 24 of hourly sums of extraterrestrial radiation

DayLength

day length in hours

Details

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

Examples

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