sirad (version 2.3-3)

sucal: Calibrate Supit-Van Kappel model

Description

Function estimates Supit-Van Kappel model coefficients 'A', 'B' and 'C' based on reference data

Usage

sucal(days, lat, rad_mea, extraT=NULL, tmax, tmin, cc)

Arguments

days

Vector of class 'Date' of length n.

lat

Latitude in decimal degrees.

rad_mea

Vector of length n containing reference (e.g. measured) solar radiation [MJm-2].

extraT

Optional. Vector of length n of extraterrestrial solar radiation [MJm-2]. If 'NULL' then it is calculated by the function. Providing extraterrestrial solar radiation speeds up the computation

tmax

Vector of length n containing daily maximum temperature [C].

tmin

Vector of length n containing daily minumum temperature [C].

cc

Vector of length n containing daily cloud coverage [octas].

Value

Vector of length 3: Vector of length 3:

Details

Function estimates Supit-Van Kappel model coefficients 'A', 'B' and 'C' based on reference (e.g. measured) solar radiation data. It performs a linear regression.

References

Supit, I. 1994. Global radiation. Publication EUR 15745 EN of the Office for Official Publications of the EU, Luxembourg. Supit, I., Kappel, R.R. van, 1998. A simple method to estimate global radiation. Solar Energy, 63:147-160.

See Also

'su'.

Examples

data(Metdata)
tmax <- Metdata$meteo$TEMP_MAX
tmin <- Metdata$meteo$TEMP_MIN
days <- Metdata$meteo$DAY
lat <- Metdata$LATITUDE
rad_mea <- Metdata$meteo$RAD_MEA
CC <- Metdata$meteo$CLOUD_DAYTIME_TOTAL
sucal(lat=lat,days=days,rad_mea, extraT=NULL,tmax=tmax, tmin=tmin,cc=CC)