Composite Scans
Composite Scans are global irradiance spectra provided in comma-separated ASCII format. There are two header rows, followed by solar data:
- Header line 1:
Start Time, End Time, Duration - Header line 2:
Number of rows of solar data, solar zenith angle, solar azimuth angle - Line 3 - last line:
Wavelength in nm, spectral irradiance in µW/(cm2 nm), TSI reading (only every 10th row).
- S = site code (A = McMurdo Station; B = Palmer Station; C = South Pole Station)
- D = Scan type (D stands for solar scan)
- YY = Year
- HH = Hour at start of scan
- MM = Minute at start of scan
- DDD = Julian Day
Note that the file format of composite scans has changed since the beginning of network operation. Please consult Operations Reports for details.
Remark:
TSI stands for "Total Scene Irradiance" sensor. The sensor consists
of a filtered photodiode that is an integral part of the system.
TSI measurements give an indication of the change of solar irradiance during
the duration of a composite scan, for example due to clouds.
For more information, see Section 2.1.2 of the Operations Report.