satellite (version 0.2.0)

calcTOAIrradTable: Get top of atmosphere solar irradiance using readily tabulated values

Description

Get mean extraterrestrial solar irradiance (ESun) using published values.

Usage

# S4 method for Satellite
calcTOAIrradTable(x, normalize = TRUE, esd)
# S4 method for factor
calcTOAIrradTable(x, normalize = TRUE, esd)
# S4 method for character
calcTOAIrradTable(x, normalize = TRUE, esd)

Arguments

x

A Satellite object or sensor id ("LC4/5/7") as character.

normalize

Logical; if TRUE, ESun is normalized to mean earth-sun distance.

esd

Earth-sun distance (AU, can be estimated using calcEarthSunDist). If x is a Satellite object and esd is not supplied and necessary for normalization, it is tried to take it from the metadata, otherwise it is estimated by the day of the year using calcEarthSunDist.

Value

Satellite object with ESun information added to the metadata

Vector object containing ESun for the respective band(s)

Vector object containing ESun for the respective band(s)

Details

Currently implemented sensors are Landsat 4, 5 and 7.

If results should not be normalized to a mean earth-sun distance, the actual earth-sun distance is approximated by the day of the year using calcEarthSunDist.

References

Tabulated values of the solar irradiance for Landsat 4 and 5 are taken from Chander G, Markham B (2003) Revised Landsat-5 TM radiometric calibration procedures and postcalibration dynamic ranges. IEEE Transactions on Geoscience and Remote Sensing 41/11, doi:10.1109/LGRS.2007.898285, online available at http://landsathandbook.gsfc.nasa.gov/pdfs/L5TMLUTIEEE2003.pdf.

Tabulated values of the solar irradiance for Landsat 7 are taken from NASA's Landsat7 handbook, tab 11.3 (Thuillier spectrum).

See Also

calcTOAIrradRadRef for the computation of the solar irradiance based on maximum radiation and reflection values of the dataset or calcTOAIrradModel for the computation of the solar irradiance based on look-up tables for the sensor's relative spectral response and solar irradiation spectral data.

See calcEarthSunDist for calculating the earth-sun distance based on the day of the year which is called by this function if ESun should be corrected for actual earth-sun distance.

Examples

# NOT RUN {
path <- system.file("extdata", package = "satellite")
files <- list.files(path, pattern = glob2rx("LE7*.tif"), full.names = TRUE)
sat <- satellite(files)
calcTOAIrradTable(sat)

calcTOAIrradTable(x = "LE7", normalize = FALSE,
                  calcEarthSunDist("2015-01-01"))
# }