Tomorrow is Earth Day, an apt moment to ponder the ways digital billboards and other forms of outdoor advertising create light pollution and squander energy. And while we’re on the subject, we might think about how our physical and mental health may suffer from these effects.
Even though digital billboards use energy-efficient LED lights, the sheer number of lights in a single sign and the fact that these billboards have to be brightly-lit in order to be seen during daylight hours turns them into energy hogs. Light pollution and light trespass are more difficult to quantify, although people who have had light cast into their windows at night by the rapidly-changing images can testify to the deleterious effect on their quality of life.
The American Medical Association was concerned enough about the issue to adopt a resolution last year calling for light pollution reduction efforts at the national, state, and local levels. According to the resolution, light trespass “has been implicated in disruption of the human and animal circadian rhythm, and strongly suspected as an etiology of suppressed melatonin production, depressed immune systems, and increase in cancer rates such as breast cancers…”
Among non-digital billboards and other signs, the growing practice of lighting them from below is a major contributor to light pollution. In fact, the State of California’s Outdoor Lighting Standards Synopsis defines light pollution as “outdoor lighting that is directed or reflected to the sky. It creates sky glow that inhibits visibility of stars and changes the whole character of the night sky.” As for light trespass, which the state defines as “unwanted light from a neighboring property”, the Lighting Standards Synopsis has this to say: “Light trespass is annoying, but it can also be a serious nuisance or even a serious health and safety risk if it adversely affects visibility for other tasks. Light trespass may also be a source of glare, including disabling, discomfort, veiling luminance, and annoyance glare that can also be serious public health and safety risk.”
For more on light pollution and its negative effects, see the website of the International Dark Sky Association.