DARK SKY EDUCATION + RESOURCES
WHAT IS LIGHT POLLUTION?
Most of us are familiar with air, water, and land pollution, but did you know that light can also be a pollutant?
The inappropriate or excessive use of artificial light – known as light pollution – can have serious environmental consequences for humans, wildlife, and our climate.
Components of light pollution include:
Glare – excessive brightness that causes visual discomfort
Skyglow – brightening of the night sky over inhabited areas
Light Trespass – light falling where it is not intended or needed
Clutter – bright, confusing and excessive groupings of light sources
The fact is that much outdoor lighting used at night is inefficient, overly bright, poorly targeted, improperly shielded, and, in many cases, completely unnecessary. This light, and the electricity used to create it, is being wasted by spilling it into the sky, rather than focusing it on to the actual objects and areas that people want illuminated.
WHAT ARE THE EFFECTS OF LIGHT POLLUTION?
Did you know exposure to artificial light at night can harm your health?
Humans evolved to the rhythms of the natural light-dark cycle of day and night. The spread of artificial lighting means most of us no longer experience truly dark nights.
Research suggests that artificial light at night can negatively affect human health, increasing risks for obesity, depression, sleep disorders, diabetes, breast cancer and more.
WILDLIFE & ECOSYSTEMS
Plants and animals depend on Earth’s daily cycle of light and dark rhythm to govern life-sustaining behaviors such as reproduction, nourishment, sleep and protection from predators.
Scientific evidence suggests that artificial light at night has negative and deadly effects on many creatures including amphibians, birds, mammals, insects and plants.
IDA estimates that least 30 percent of all outdoor lighting in the U.S. alone is wasted, mostly by lights that aren’t shielded. That adds up to $3.3 billion and the release of 21 million tons of carbon dioxide per year! To offset all that carbon dioxide, we’d have to plant 875 million trees annually.
RESPONSIBLE OUTDOOR LIGHTING
Too often, outdoor electric lighting installations at night are over lit, left on when not needed, and are harmful to the environment. As a result, light pollution is a growing global issue that can negatively affect our environment and impact our quality of life.
By applying these principles, properly designed electric lighting at night can be beautiful, healthy, and functional. Projects that incorporate these principles will save energy and money, reduce light pollution, and minimize wildlife disruption.