photoperiodGrid: Photoperiod

In SantanderMetGroup/drought4R: A climate4R package for PET estimation and drought assessment <http://www.meteo.unican.es/climate4R>

Photoperiod

Description

Compute photoperiod (daylength) as a funtion of latitude and date

Usage

photoperiodGrid(c4r.obj)

Arguments

c4r.obj

climate4R object. Note that this is independent of the variable stored, as it will use only the calendar an geographical information of the object to compute the photoperiod

Details

This is just a wrapper from the daylength function of package geosphere.

Author(s)

J. Bedia

Examples

require(transformeR)
data("tasmin.eobs.iberia.daily")
daylength <- photoperiodGrid(tasmin.eobs.iberia.daily)
lat <- range(getCoordinates(daylength)[["y"]])
lat.ranges <- seq(from = lat[1], to = tail(lat, 1), length.out = 5)
lat.list <- lapply(1:(length(lat.ranges) - 1), function(x) {
    subsetGrid(daylength, latLim = c(lat.ranges[x], lat.ranges[x + 1]), outside = TRUE)
})
require(visualizeR)
temporalPlot(lat.list, xyplot.custom = list(main = "Photoperiod as a function of latitude",
                                            ylab = "Daylight hours",
                                            xlab = "Date",
                                            key = list(corner = c(1,.5),
                                                       lines = list(col = 1:4),
                                                       horizontal = TRUE,
                                                       text = list(c("37ºN","39ºN","41ºN","43ºN")))))

SantanderMetGroup/drought4R documentation built on Feb. 7, 2024, 1:59 a.m.