A named list of reference spectral irradiance data frames representing
five standard illumination conditions, derived from the ASTM G173-03
global-tilt spectrum. Used by solar_irradiance.
Format
A named list of five data frames, each with columns:
- wavelength
Wavelength in nm (300 to 800, step 10).
- irradiance
Spectral irradiance in W/m^2/nm.
Names: clear_noon, clear_dawn, overcast,
underwater_1m, underwater_10m.
Each data frame has attributes condition,
reference_depth_m, and reference_medium. Reference depth is
measured in metres from the water surface; the three atmospheric spectra
use depth 0 in "air", and the underwater spectra use depths 1 and
10 in "water", respectively.
Source
ASTM G173-03(2012) Standard Tables for Reference Solar Spectral Irradiances. American Society for Testing and Materials, West Conshohocken, PA.
Examples
solar_irradiance("clear_noon")
#> wavelength irradiance
#> 1 300 0.00
#> 2 310 0.01
#> 3 320 0.14
#> 4 330 0.36
#> 5 340 0.65
#> 6 350 0.89
#> 7 360 1.12
#> 8 370 1.22
#> 9 380 1.12
#> 10 390 1.02
#> 11 400 1.00
#> 12 410 1.22
#> 13 420 1.43
#> 14 430 1.47
#> 15 440 1.51
#> 16 450 1.56
#> 17 460 1.60
#> 18 470 1.66
#> 19 480 1.72
#> 20 490 1.78
#> 21 500 1.84
#> 22 510 1.88
#> 23 520 1.90
#> 24 530 1.90
#> 25 540 1.88
#> 26 550 1.85
#> 27 560 1.81
#> 28 570 1.76
#> 29 580 1.72
#> 30 590 1.67
#> 31 600 1.62
#> 32 610 1.57
#> 33 620 1.52
#> 34 630 1.47
#> 35 640 1.42
#> 36 650 1.37
#> 37 660 1.32
#> 38 670 1.26
#> 39 680 1.20
#> 40 690 1.14
#> 41 700 1.08
#> 42 710 1.02
#> 43 720 0.96
#> 44 730 0.90
#> 45 740 0.84
#> 46 750 0.78
#> 47 760 0.72
#> 48 770 0.66
#> 49 780 0.60
#> 50 790 0.54
#> 51 800 0.48