All-Weather Comparison between Spectral and Broadband (Robertson-Berger) UV Measurements

authored by: Bernhard Mayer, Gunther Seckmeyer
Abstract: Spectral measurements of UV irradiance at the Fraunhofer Institute at Garmisch-Partenkirchen, Germany, are intercompared with data from two different Robertson-Berger-type meters. More than 21000 spectra gathered during 20 months of continuous operation were used for this analysis, sampling a large variety of atmospheric conditions. At low solar zenith angles the agreement (±10%) was quite satisfactory, whereas at high solar zenith angles the broadband instruments gave systematically lower readings than the erythemally weighted spectral data. The deviation of the spectral response of the broadband instruments from the Commission Internationale de l'Eclairage (CIE) erythema function and the cosine error provide an explanation of the observed differences that are similar for both broadband meters. Model calculations agree quite well with the observations, if an accurate measurement of the broadband spectral response is available. An analytical fit curve was established for the ratio between broadband and weighted spectral data, as a function of solar zenith angle, enabling quick and easy checks of the stability of the spectroradiometric system. The relative standard deviation of the data from the fit function was only 2-3% in the case of cloudless sky conditions and 5% for all sky conditions, including all types of systematic and instrumental errors.
External Organisation(s): Karlsruhe Institute of Technology (KIT)
Type: Article
Journal: Photochemistry and photobiology
Volume: 64
Pages: 792-799
No. of pages: 8
ISSN: 0031-8655
Publication date: 11.1996
Publication status: Published
Peer reviewed: Yes
ASJC Scopus subject areas: Biochemistry, Physical and Theoretical Chemistry
Electronic version(s): https://doi.org/10.1111/j.1751-1097.1996.tb01836.x (Access: Unknown)

BibTeX

@article{4b33c67f50114efc862f94d27ff79396,
title = "All-Weather Comparison between Spectral and Broadband (Robertson-Berger) UV Measurements",
abstract = "Spectral measurements of UV irradiance at the Fraunhofer Institute at Garmisch-Partenkirchen, Germany, are intercompared with data from two different Robertson-Berger-type meters. More than 21000 spectra gathered during 20 months of continuous operation were used for this analysis, sampling a large variety of atmospheric conditions. At low solar zenith angles the agreement (±10%) was quite satisfactory, whereas at high solar zenith angles the broadband instruments gave systematically lower readings than the erythemally weighted spectral data. The deviation of the spectral response of the broadband instruments from the Commission Internationale de l'Eclairage (CIE) erythema function and the cosine error provide an explanation of the observed differences that are similar for both broadband meters. Model calculations agree quite well with the observations, if an accurate measurement of the broadband spectral response is available. An analytical fit curve was established for the ratio between broadband and weighted spectral data, as a function of solar zenith angle, enabling quick and easy checks of the stability of the spectroradiometric system. The relative standard deviation of the data from the fit function was only 2-3% in the case of cloudless sky conditions and 5% for all sky conditions, including all types of systematic and instrumental errors.",
author = "Bernhard Mayer and Gunther Seckmeyer",
note = "Copyright: Copyright 2017 Elsevier B.V., All rights reserved.",
year = "1996",
month = nov,
doi = "10.1111/j.1751-1097.1996.tb01836.x",
language = "English",
volume = "64",
pages = "792--799",
journal = "Photochemistry and photobiology",
issn = "0031-8655",
publisher = "Wiley-Blackwell",
number = "5",
}