OCT 02, 2014 12:00 AM PDT

Would We be Better Off Left in the Dark?

WRITTEN BY: Peter Micheli
Did you know that the word "galaxy" comes from the Greek work for milk because the night sky was so awash with stars that it had a milky appearance? Well, that's all changed because of the artificial light produced by our civilization. Formed in 1988, The International Dark-Sky Association (IDA) is trying to mitigate the effects of all this light, and reduce light pollution. On its website, the IDSA summarizes the problems caused by light pollution as such, "Light pollution wastes energy, affects astronomers and scientists, disrupts global wildlife and ecological balance, and has been linked to negative consequences in human health."

Two major elements of light pollution are sky glow and light trespass. Sky glow is caused when light fixtures emit a portion of their light directly upward, where it scatters and creates the orange-yellow glow you can see above a city. This effect interferes with astronomical instruments' capability to capture light from space. Light trespass occurs when fixtures cast light into areas where it is not wanted, such as neighboring properties.

Artificial light effects wildlife in many ways. Lighted towers and tall buildings can confuse birds, bats, and moths. Newly hatched sea turtles use the moon to guide them toward the ocean, but when the moon is no longer the brightest light in the area, they can become confused and be lured to dangerous roads and predators. Artificial light also interferes with species that communicate using light such as glowworms and fireflies. Some effects are not so obvious. For example, the sky glow around sports stadiums can stop nearby frogs from mating.

There is also research to show that artificial light negatively affects humans. Consistent periods of light and dark are important to the proper operation of our circadian rhythms which are needed for good health. The Word Health Organization's International Agency for Research on Cancer has listed "shiftwork that involves circadian disruptions as being "probably carcinogenic to humans."

The Arizona Republic recently published a report on the decline of dark areas, a situation that can be more pronounced in desert areas as large, bright cities encroach on dark areas. In it, they state, "Scientists estimate that in about 10 years, America will have only three dark patches of land where people will be able to clearly see the Milky Way and where they'll be able to do high-quality astronomy and nocturnal wilderness research. Those areas are southeastern Oregon and western Idaho; northeastern Nevada and western Utah; and northern Arizona and southeastern Utah - the better part of the Colorado Plateau." But, light from Las Vegas and Phoenix threaten the darkness in the Colorado Plateau and Nevada/Utah areas.

Efforts to preserve darkness can be very effective. Tucson implemented dark-skies friendly lighting codes decades ago and the city has not gotten brighter in 30 years even though its population has increased by 59% during that time. And, reducing light pollution is not all that complicated, but ordinances and enforcement must be in place. Just reevaluating how much light is really needed in certain places and certain times can help. Using sensors and timers will reduce wasted light. Shielding lights so their glow only points down can reduce light in the night sky. The color of the light is also important. Changing to amber light can create less sky glow. Sometimes less light is better for visibility. For example reflectors on the edge of highways and guide lights on runways work better than floodlights, because they cause contrast, not brightness.

In addition to the obvious ecological, practical, and economic reasons for preserving darkness, there is a deeper, almost spiritual need to see the stars. Grand Canyon park ranger Marker Marshall sums it up this way, "People need the sense of beauty and perspective and awe that we get from our exposure to the universe in a dark night sky. It's part of every culture, part of being human - to contemplate what's above us."
About the Author
You May Also Like
JAN 15, 2020
Earth & The Environment
JAN 15, 2020
Glacial Floods: The Lesser-Known Climate Change-Related Disaster
Natural phenomena such as wildfires and hurricanes are intensifying due to climate change, but have you heard of glacial floods? This lesser-known threat,...
JAN 17, 2020
Earth & The Environment
JAN 17, 2020
What's the carbon footprint of your fish stick?
New research from scientists at the University of California, Santa Cruz highlights the unsustainable footprint of the processed fish industry. The study, ...
JAN 20, 2020
Plants & Animals
JAN 20, 2020
Horned Lizards Do Anything to Protect Their Eggs From Predators
When a female horned lizard lays her eggs, she finds herself up against several predators that want to devour them. Fortunately, the female horned lizard d...
JAN 27, 2020
Earth & The Environment
JAN 27, 2020
Study Suggests That Vineyards can Adapt to Climate Change
Researchers from the University of British Columbia (UBC) have some good news for wine lovers. Delicate wine grapes are highly susceptible to changes in te...
MAR 02, 2020
Earth & The Environment
MAR 02, 2020
New coral gardens discovered in ocean's depths
Bremer Canyon Marine Park sits in the Indian Ocean off the southern coast of Western Australia, a 4472 km² marine protected area teeming with marine b...
MAR 19, 2020
Earth & The Environment
MAR 19, 2020
What's the Ocean's Oxygen Budget?
Have you heard the statement, “every other breath you take comes from the ocean?” Oxygen-producing phytoplankton are just one part of the oxyge...
Loading Comments...