Standard Solar Spectra: MODTRAN ETR Spectra

What is ETR? 

Another expression of Standard Solar Spectraat top of atmosphere

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

Standard Solar Spectra are commonly used as reference for radition transfer research and application. The MODTRAN® (MODerate resolution atmospheric TRANsmission) software provide ETR in its setup directory (Data).

1) The directory is like "\SpectralSciencesInc\MODTRAN\5.2.2\DATA" in MODTRAN version 5. ETR,at the equivalent of 1 cm-1, 5 cm-1, and 15 cm-1 resolution, are stored intab delimited text file(.dat) files: 

SUN01cebchkur.dat, SUN01chkur.dat, SUN01fontenla.dat, SUN01kurucz1995.dat, SUN01kurucz1997.dat, SUN01kurucz2005.dat, SUN01thkur.dat   ...

SUN05highSORCE.dat, SUN05kurucz1995.dat, SUN05lowSORCE.dat, SUN05quietSORCE.dat

SUN15highSORCE.dat, SUN15kurucz1995.dat, SUN15lowSORCE.dat, SUN15quietSORCE.dat

2) The directory is like "\PcModWin40\Bin\Data" in MODTRAN version 4. ETR, at the equivalent of 1 cm-1 resolution, are stored in tab delimited text file(.dat) files: 

cebchkur.dat, chkur.dat, newkur.dat, thkur.dat, ...

This site also provides the MODTRAN ETR spectra, at the equivalent of 1 cm-1 resolution, have been grouped in a tab delimited text file. The file includes Chance+Kurucz (MChKur), Cebula+Kurucz (MCebKur), New Kurucz (MNewKur), Thullier+Kurucz (MThKur), Old Kurucz (MOldKur) and the Wherli 1985 (MWherli_WMO) spectra; based on combinations of data from the references cited below. These spectra contain 49,951 wavelengths, except for the MOldKur.dat, which contains 49,934 wavelengths. The original spectral step size (resolution) is normally 1 cm-1 for these files.

NOTE: These spectra have been converted to wavelength (nm), irradiance (W m-2 nm-1)units from the units of wavenumber (cm-1) vs irradiance (W cm-2 cm-1) used in MODTRAN.

Reference:

http://rredc.nrel.gov/solar/spectra/am0/modtran.html

http://www.rfcafe.com/references/electrical/ASTM-G173-03-Reference-Spectra.htm