Overnight measurements of the sky brightness as a method for assessing the cloudiness

Abstract

Determining the state of cloudiness at night is always a problem, especially at low levels of light pollution. This paper presents an innovative method of assessing the cloudiness of the night sky solely on the basis of all-night measurements of the brightness of the sky using generally available SQM meters. Using the numerical method of calculating the discrete derivative of the overnight brightness of the night sky from time it is possible not only to distinguish a cloudless sky from a cloudy one, but even to distinguish the high level clouds from medium and low level ones. Full Text: PDF ReferencesKyba C.C.M., Ruhtz T., Fischer J., Hölker F., Cloud Coverage Acts as an Amplifier for Ecological Light Pollution in Urban Ecosystems, PLoS ONE, vol. 6, no. 3, 2011, e17307. CrossRef Ściężor T., The impact of clouds on the brightness of the night sky, to be published in Journal of Quantitative Spectroscopy and Radiative Transfer, 2020 CrossRef Ściężor T., Kubala M., Kaszowski W., Light Pollution of the Mountain Areas in Poland, Archives of Environmental Protection, Vol.38, No.4, 2012, pp. 59-69. CrossRef Crawford D.L., Photometry: terminology and units in the lighting and astronomical sciences, The Observatory, vol. 117, 1997, pp. 14-18. DirectLink Ściężor T., Kubala M., Particulate matter as an amplifier for astronomical light pollution, Monthly Notices of the Royal Astronomical Society, vol. 444, no. 3, 2014, pp. 2487-2493. CrossRef