The concept of light pollution and related concepts
The concept of light pollution has been introduced in astronomy in the 70s of 20th century and meant brightening of the night sky due to artificial ground light scattering in the atmosphere. Similarly sounding term photopollution was proposed in 1985 [86] in the biological sciences to denote harmful effects of artificial light on living organisms. Currently, the concept of light pollution has been well assimilated in these areas, therefore, one distinguish between astronomical light pollution and ecological light pollution . The light pollution in the interdisciplinary meaning is understood, therefore, as a whole, adverse events related to the use of human artificial lighting. The light pollution is usually distinguished by the following three main adverse effects: glare - very strong direct effect of light on the sense of sight of humans and animals (blindness), trespass - lighting the area adjacent to intentionally illuminated (especially lighting of the windows of residential buildings or protected areas adjacent to the illuminated area) and the sky glow - lighting the night sky by the artificial light scattering in the atmosphere. Latter term is often equated with astronomical light pollution, while the first two identified with ecological light pollution.
Such identification is not accurate, both in the first and in the second case. The second category also includes such phenomena as the over-illumination, the light cluttering or the light energy waste. On the other hand, often the sky glow is generally meaning as the overall lighting of the night sky by the diffuse light - even this natural. In this case, an artificial componen is called the artificial sky glow and this term is most commonly identified in the literature as the astronomical light pollution. Consequently, according to this identification the artificial sky glow is often understood as a brightening of the sky in the conditions of the good sky visibility, ie in the absence of clouds or fog. Therefore, the term best reflects the general phenomena associated with the scattering of artificial light in the atmosphere is the atmospherical light pollution. The last term accurately describes the research phenomenon. However, due to the fact that it is rarely used in the literature, in this web page we use both the terms of astronomical light pollution and atmospherical light pollution, and also sky glow, but interpreting it more broadly as the general phenomena of scattering of the artificial light in an atmosphere.