Following is the full transcript of former park ranger Diane Knutson’s TEDx Talk titled “Why We Need Darkness to Survive” at TEDxRapidCity conference. In this talk, Diane shares why light pollution needs to be reduced and some surprisingly simply ways we can all take action.
This meadowlark perches on a prairie flower singing its mating song. It’s customary for meadowlarks to sing toward the rising sun.
This one, however, was mistaken by the lights of Rapid City at 2 AM. Despite being 60 miles south of the Rapid City border and well within the boundaries of Wind Cave National Park, this songbird was singing out much too late to attract a mate.
Have you ever tried attracting a mate by calling them at 2 AM? My mother told me nothing good happens after midnight.
So why was this songbird so confused, mistaking the bright lights of Rapid City for the rising sun at 2 AM?
Improper lighting and the over-illumination of residential neighborhoods, business signage, and street lights brighten our night sky, creating an orange hue above the city for miles outside its border.
Over 100 years ago, all creatures could look up and see a spectacular starry night sky. But now, eight out of ten children will never see the Milky Way from where they live.
Light pollution doesn’t only impact our view of the universe, it also impacts our environment, our individual health, and energy consumption.
The three main components of light pollution include sky glow as well as glare and light trespass, which I will also explain.
Glare is the excessive brightness that causes us visual discomfort. We often illuminate areas in attempt to increase safety. As children, we’re afraid of the dark, so we flip on a night switch because “the night is dark and full of terrors.” And as adults, we do that now on a much grander scale.