Light Pollution

Light pollution refers to artificially produced light, particularly in urban environments at night. This phenomenon is often referred to as light at night (LAN) or artificial light at night (ALAN) and is particularly important to people such as shift-workers who may not .

The light disrupts the circadian rhythms of humans and wildlife alike as well as lowering melatonin production, which results in sleep deprivation, fatigue, headaches, stress, anxiety, and other health problems (source). Furthermore, LAN has been associated with increased breast cancer incidents in shift-working women (source).

The SRS represents light pollution in radiance based on satellite annual averages. As with air pollution, the scale starts at zero because the desired amount is virtually none at night. Of course, in practice there are street lights and signs that serve a purpose but this is where individual exposure becomes an important determinant of the actual effect of LAN, as the studies on this subject make clear.

How light pollution is an urban planning problem

As defined by Darksky.org; Light pollution is a side effect of industrial civilization. Its sources include building exterior and interior lighting, advertising, commercial properties, offices, factories, streetlights, and illuminated sporting venues.