Light pollution is the human-made alteration of outdoor light levels from those occurring naturally. Every light alters the night. Light pollution can negatively affect both humans and wildlife.
In humans, artificial light disrupts natural circadian rhythms, leading to sleep disturbances. Poor sleep can lead to overall health issues such as increased stress and anxiety. Nocturnal animals (of which Colorado has many) can be disoriented or attracted to artificial light sources, impacting their foraging, mating and migration patterns. Light pollution can also lead to increased predation on animals, as well as negatively affecting their mating.
Components of light pollution include:
• Glare: excessive brightness that causes visual discomfort (especially for older eyes).
• Light trespass: light falling where it is not intended or needed.
• Skyglow: brightening of the night sky over inhabited areas.
• Clutter: bright, confusing, and excessive groupings of light sources.
Taking action
We have begun measuring sky quality in Pagosa in order to gather data and establish current status. A handheld sky quality meter is used to do this. We will publish our readings later in 2025 with further explanation of our process.
However, a few citizens measuring light pollution will not make it better.
Limiting outdoor lighting is a community-wide effort. Each of us can make a difference by making inexpensive, simple changes to outdoor lighting as defined by DarkSky International, the globally recognized authority on light pollution.
Using lower-lumen, warm-colored bulbs at your home or business can also save money.
Take action. Take pride in preserving Pagosa’s dark sky for generations to come. Dark-sky friendly fixtures are fully shielded with bulbs with less than 800 lumens (450 for home lighting) and 3,000K in temperature (2,700K for most applications).
