R/uvi.wb.r

In photobiologyWavebands: Waveband Definitions for UV, VIS, and IR Radiation

#' Constructor of CIE weighted waveband
#'
#' UVI (UV Index) based on Erythema BSWF
#'
#' @param std "NOAA" or "WMO"
#' @return a list defining the wavelength range, weighting and normalization.
#'   This is just the CIE98 BSWF but with the wavelength limits adjusted to
#'   those used for UVI.
#'
#' @description This is just a convenience function that returns the same
#'   weights as \code{CIE} as defined by \code{CIE_e_fun} but with no option to
#'   change normalization wavelength, and with the wavelength limits adjusted to
#'   those used for UVI. Using std="NOAA" follows the definition in
#'   \url{https://www.esrl.noaa.gov/gmd/grad/neubrew/docs/UVindex.pdf} but using
#'   CIE98 as SWF. NOAA definition discards wavelengths shorter than 286.5 nm as
#'   when calculated based on spectral data from Brewer instruments. "WMO" uses
#'   the internationally accepted lower limit at 250 nm. "NOAA" is the default
#'   as this is safer with noisy data for sunlight, and for solar radiation the
#'   value of UVI should be correct. When calculating UVI for radiation spectra
#'   from UV lamps, "WMO" should be used.
#'
#' @references World Health Organization, World Meteorological Organization,
#'   United Nations Environment Programme & International Commission on
#'   Non-Ionizing Radiation Protection.  (2002) Global Solar UV Index: A
#'   Practical Guide. World Health Organization, Geneva. ISBN 9241590076.
#'   \url{https://apps.who.int/iris/handle/10665/42459}
#'
#' P. Kiedron, S. Stierle and K. Lantz (2007) Instantaneous UV Index and Daily
#' UV Dose Calculations. NOAA-EPA Brewer Network.
#' \url{https://www.esrl.noaa.gov/gmd/grad/neubrew/docs/UVindex.pdf}
#'
#' @seealso \code{\link{UVI}}
#'
#' @keywords internal

UVI_wb <- function(std = "NOAA") {
  label <- "UVIndex"
  if (std == "NOAA") {
    w.low = 286.5
  } else if (std == "WMO" | std == "WHO") {
    w.low = 250.0
  } else {
    w.low = 250.0
    warning("Unrecognized value for UVI std '", std, "', using 'WMO'.")
  }
  new_waveband(
    w.low = w.low,
    w.high = 400,
    weight = "SWF",
    SWF.e.fun = CIE_e_fun,
    SWF.norm = 298.0,
    norm = 298.0,
    hinges = c(249.99, 250, 298, 328, 399.99, 400),
    wb.name = paste(label, std, sep = "."),
    wb.label = label
  )
}