site_adapt: Site Adaptation of Solar Irradiance Modeled Series with Coincident Ground Measurements

Description

Site Adaptation of Solar Irradiance Modeled Series with Coincident Ground Measurements

Usage

site_adapt(
  Target,
  latitude_target,
  z_target,
  Calibration,
  latitude_calibrat,
  z_calibrat,
  timezone,
  GHI_threshold,
  DNI_threshold
)

Arguments

Target

Dataframe object with solar radiation series to be adapted including time (with same time zone as subset_calibrating_period), the solar irradiance modeled series to be site adapted, along with their clear sky index and solar elevation (degrees)

latitude_target

Site latitude of solar radiation series to be adapted (degrees, +N)

z_target

Site elevation above sea level of solar radiation series to be adapted (m)

Calibration

Dataframe object with solar radiation series for calibrating including time (with same time zone as subset_target_period), solar irradiance modeled and measured series, along with modeled clear sky index and solar elevation (degrees)

latitude_calibrat

Site latitude of solar radiation series for calibrating (degrees, +N)

z_calibrat

Site elevation above sea level of solar radiation series for calibrating (m)

timezone

Time zone specification of the calibration_period and target_period datasets

GHI_threshold

Upper limit of GHI series (same units that Target). For automatic calulation from observed data, set it to -99

DNI_threshold

Upper limit of DNI series (same units that Target). For automatic calulation from observed data, set it to -99

Value

Dataframe object including time and site adapted solar irradiance series

References

Fern<U+00E1>ndez-Peruchena, C.M.; Polo, J.; Mart<U+00ED>n, L.; Mazorra, L. Site-Adaptation of Modeled Solar Radiation Data: The SiteAdapt Procedure. Remote Sens. 2020, 12, 2127.

Examples

Run this code

# NOT RUN {
# A site located in the the Namib Desert of Namibia (Gobabeb, GOB) is selected

# - latitude:   23.5614 S
# - Longitude:  15.0420 E
# - Elevation:  407.0 m asl

 # Load calibration and modeled datasets
   data(calibration_2016) # Measured from BSRN
   data(target_2013_2016) # Provided by CAMS-RAD service

target_2013_2016$time = as.POSIXct(
paste(target_2013_2016$Year, "-",
target_2013_2016$Month, "-",
target_2013_2016$Day, " ",
target_2013_2016$Hour, ":",
target_2013_2016$Minute, sep=""),
tz ="UTC")

# }
# NOT RUN {
 # Apply the site adaptation procedure
   site_adapted_series = site_adapt(
   Target = target_2013_2016,
   latitude_target = -23.5614, # Latitude of target site
   z_target = 407.0, # Elevation of target site
   Calibration = calibration_2016,
   latitude_calibrat = -23.5614, # Same location of target period
   z_calibrat = 407.0, # Same location of target period
   timezone = "UTC",
   GHI_threshold = -99, # The threshold is calculated from observed data
   DNI_threshold = -99) # The threshold is calculated from observed data


# Load measured data for evaluating the site adaptation performance:
   data(observed_2013_2016)

# Merge datasets

site_adapted_series$time = as.POSIXct(
paste(site_adapted_series$Year, "-",
site_adapted_series$Month, "-",
site_adapted_series$Day, " ",
site_adapted_series$Hour, ":",
site_adapted_series$Minute, sep=""),
tz ="UTC")

observed_2013_2016$time = as.POSIXct(
paste(observed_2013_2016$Year, "-",
observed_2013_2016$Month, "-",
observed_2013_2016$Day, " ",
observed_2013_2016$Hour, ":",
observed_2013_2016$Minute, sep=""),
tz ="UTC")


meas_model = merge(observed_2013_2016[,6:9],
target_2013_2016[,c(6:9,11)],
by = "time", all = FALSE )

meas_model_adapt = merge(meas_model,
site_adapted_series[,6:10],
by = "time", all = FALSE )


# Display scatterplots
library(RColorBrewer)
pal <- rev(brewer.pal(11,"Spectral"))
pal=pal[2:11]

library(ggplot2)
scatter_DNI.obs = ggplot() +
geom_hex(data=meas_model_adapt,aes(x=DNI.obs, y = DNI.mod),bins = 125, alpha = 1) +
scale_fill_gradientn(colours = pal)+ theme_light() +
xlab(expression(paste("Measured DNI (W / ", m^2, " )", sep=""))) +
 ylab(expression(paste("Modeled DNI (W / ", m^2, " )", sep=""))) +
 theme(legend.position = "none") +
 xlim(100, 1120) + ylim(100,1120) +
geom_abline(intercept = 0, slope = 1, color="purple", linetype="solid", size=1.5, alpha = 0.5)

plot_DNI_adapt = ggplot() +
geom_hex(data=meas_model_adapt,aes(x=DNI.obs, y = DNI_adapted),bins = 125, alpha = 1) +
 scale_fill_gradientn(colours = pal)+ theme_light() +
 xlab(expression(paste("Measured DNI (W / ", m^2, " )", sep=""))) +
 ylab(expression(paste("Adapted DNI (W / ", m^2, " )", sep=""))) +
 theme(legend.position = "none") + xlim(100, 1120) + ylim(100,1120) +
 geom_abline(intercept = 0, slope = 1, color="purple", linetype="solid", size=1.5, alpha = 0.5)

library(ggpubr)
ggarrange(scatter_DNI.obs, plot_DNI_adapt)

scatter_GHI.obs = ggplot() +
geom_hex(data=meas_model_adapt,aes(x=GHI.obs, y = GHI.mod),bins = 125, alpha = 1) +
 scale_fill_gradientn(colours = pal)+ theme_light() +
 xlab(expression(paste("Measured GHI (W / ", m^2, " )", sep=""))) +
 ylab(expression(paste("Modeled GHI (W / ", m^2, " )", sep=""))) +
 theme(legend.position = "none") + xlim(100, 1180) + ylim(100,1180) +
 geom_abline(intercept = 0, slope = 1, color="purple", linetype="solid", size=1.5, alpha = 0.5)

plot_GHI_adapt = ggplot() +
geom_hex(data=meas_model_adapt,aes(x=GHI.obs, y = GHI_adapted),bins = 125, alpha = 1) +
 scale_fill_gradientn(colours = pal) + theme_light() +
 xlab(expression(paste("Measured GHI (W / ", m^2, " )", sep=""))) +
 ylab(expression(paste("Adapted GHI (W / ", m^2, " )", sep=""))) +
 theme(legend.position = "none") + xlim(100, 1180) + ylim(100,1180) +
 geom_abline(intercept = 0, slope = 1, color="purple", linetype="solid", size=1.5, alpha = 0.5)
ggarrange(scatter_GHI.obs, plot_GHI_adapt)

scatter_DHI.obs = ggplot() +
geom_hex(data=meas_model_adapt,aes(x=DHI.obs, y = DHI.mod),bins = 125, alpha = 1) +
 scale_fill_gradientn(colours = pal)+ theme_light() +
 xlab(expression(paste("Measured DHI (W / ", m^2, " )", sep=""))) +
 ylab(expression(paste("Modeled DHI (W / ", m^2, " )", sep=""))) +
 theme(legend.position = "none") + xlim(25, 700) + ylim(25, 700) +
 geom_abline(intercept = 0, slope = 1, color="purple", linetype="solid", size=1.5, alpha = 0.5)

plot_DHI_adapt = ggplot() +
geom_hex(data=meas_model_adapt,aes(x=DHI.obs, y = DHI_adapted),bins = 125, alpha = 1) +
 scale_fill_gradientn(colours = pal)+ theme_light() +
 xlab(expression(paste("Measured DHI (W / ", m^2, " )", sep=""))) +
 ylab(expression(paste("Adapted DHI (W / ", m^2, " )", sep=""))) +
 theme(legend.position = "none") + xlim(25, 700) + ylim(25, 700) +
 geom_abline(intercept = 0, slope = 1, color="purple", linetype="solid", size=1.5, alpha = 0.5)
ggarrange(scatter_DHI.obs, plot_DHI_adapt)




 # Display ECDF plots
plot_ECDF_DNI = ggplot(data=meas_model_adapt[which(meas_model_adapt$Elev > 0),])+
 stat_ecdf(aes(DNI.obs), col="firebrick", lwd = 0.75) +
 stat_ecdf(aes(DNI.mod), col="dodgerblue", lwd = 0.75) +
 stat_ecdf(aes(DNI_adapted), col="purple", lwd = 0.75) +
 theme_light() + xlab(expression(paste("DNI (W / ", m^2, " )", sep="")))+ ylab("ECDF ( - )")+
 annotate("text", x = 50, y = 0.9, label = "Measured", col="firebrick1", size = 4)+
 annotate("text", x = 50, y = 0.8, label = "Modeled", col="dodgerblue", size = 4)+
 annotate("text", x = 50, y = 0.7, label = "Adapted", col="purple", size = 4)
plot_ECDF_DNI

plot_ECDF_GHI = ggplot(data=meas_model_adapt[which(meas_model_adapt$Elev > 0),])+
 stat_ecdf(aes(GHI.obs), col="firebrick", lwd = 0.75) +
 stat_ecdf(aes(GHI.mod), col="dodgerblue", lwd = 0.75) +
 stat_ecdf(aes(GHI_adapted), col="purple", lwd = 0.75) +
 theme_light() + xlab(expression(paste("GHI (W / ", m^2, " )", sep="")))+ ylab("ECDF ( - )")+
 annotate("text", x = 50, y = 0.9, label = "Measured", col="firebrick1", size = 4)+
 annotate("text", x = 50, y = 0.8, label = "Modeled", col="dodgerblue", size = 4)+
 annotate("text", x = 50, y = 0.7, label = "Adapted", col="purple", size = 4)
plot_ECDF_GHI

plot_ECDF_DHI = ggplot(data=meas_model_adapt[which(meas_model_adapt$Elev > 0),])+
 stat_ecdf(aes(DHI.obs), col="firebrick", lwd = 0.75) +
 stat_ecdf(aes(DHI.mod), col="dodgerblue", lwd = 0.75) +
 stat_ecdf(aes(DHI_adapted), col="purple", lwd = 0.75) +
 theme_light() + xlab(expression(paste("DHI (W / ", m^2, " )", sep="")))+ylab("ECDF ( - )")+
 annotate("text", x = 25, y = 0.9, label = "Measured", col="firebrick1", size = 4)+
 annotate("text", x = 25, y = 0.8, label = "Modeled", col="dodgerblue", size = 4)+
 annotate("text", x = 25, y = 0.7, label = "Adapted", col="purple", size = 4)
plot_ECDF_DHI




# Statistical indicators
library(hydroGOF)
pbias(meas_model_adapt$GHI.mod,meas_model_adapt$GHI.obs)
pbias(meas_model_adapt$GHI_adapted,meas_model_adapt$GHI.obs)

pbias(meas_model_adapt$DNI.mod,meas_model_adapt$DNI.obs)
pbias(meas_model_adapt$DNI_adapted,meas_model_adapt$DNI.obs)

pbias(meas_model_adapt$DHI.mod,meas_model_adapt$DHI.obs)
pbias(meas_model_adapt$DHI_adapted,meas_model_adapt$DHI.obs)

rmse(meas_model_adapt$GHI.mod,meas_model_adapt$GHI.obs)
rmse(meas_model_adapt$GHI_adapted,meas_model_adapt$GHI.obs)

rmse(meas_model_adapt$DNI.mod,meas_model_adapt$DNI.obs)
rmse(meas_model_adapt$DNI_adapted,meas_model_adapt$DNI.obs)

rmse(meas_model_adapt$DHI.mod,meas_model_adapt$DHI.obs)
rmse(meas_model_adapt$DHI_adapted,meas_model_adapt$DHI.obs)
# }
# NOT RUN {


# }

Run the code above in your browser using DataLab