solar.irradiance: Standard Solar Irradiance - Extraterrestrial and Terrestrial

Description Format Details Source References See Also


Three power spectra; from 280 to 1000 nm at 1 nm intervals. Units are W*m^{-2}*nm^{-1}.

a transmittance spectrum = a ratio of 2 spectra from solar.irradiance


solar.irradiance is a colorSpec object with quantity equal to 'power' and with 3 spectra:


Extraterrestrial Radiation (solar spectrum at top of atmosphere) at mean Earth-Sun distance


spectral radiation from solar disk plus sky diffuse and diffuse reflected from ground on south facing surface tilted 37 deg from horizontal


the sum of Direct and Circumsolar irradiance, see Details

atmosphere2003 is a colorSpec object with quantity equal to 'transmittance' and with 1 spectrum:


the ratio of AirMass.1.5/AirMass.0 from solar.irradiance


Direct is Direct Normal Irradiance Nearly parallel (0.5 deg divergent cone) radiation on surface with surface normal tracking (pointing to) the sun, excluding scattered sky and reflected ground radiation.

Circumsolar is Spectral irradiance within +/- 2.5 degree (5 degree diameter) field of view centered on the 0.5 deg diameter solar disk, but excluding the radiation from the disk.



ASTM G173-03 Reference Spectra Derived from SMARTS v. 2.9.2.
Standard Tables for Reference Solar Spectral Irradiances: Direct Normal and Hemispherical on 37-deg Tilted Surface (2003)

See Also

D65, D50, daylightSpectra, vignette blueflame

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