As my husband and I were driving at night through a rural area in North Florida, he remarked, “It’s a different kind of dark out here.” I’ve often thought the same when we were in this area.
It’s a wonderful feeling to experience almost total darkness at night, but it is becoming increasingly hard to do. Our neighborhood is relatively dark and woodsy, but it is not the same kind of dark we experienced on this trip and others. I’d often heard the term light pollution and certainly complain of it — one neighbor’s light across the woods from us beams into our bedroom in the winter when the trees are bare, and my understanding husband kindly listens to my complaints.
Light pollution is a very real and very concerning problem for our earth and affects every inhabitant and our environment. Defined as inappropriate or excessive use of artificial light, light pollution can have serious environmental consequences for humans, wildlife and our climate. Light pollution can take many forms, including glare, or excessive brightness; sky glow, which drowns out the night sky over urban areas; light trespass, or stray light falling where it is not needed; and clutter, or confusing groups of bright light sources.
According to darksky.org, a leading authority on light pollution, most 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 onto the actual objects and areas that people want illuminated. Light pollution is a side effect of industrial civilization. Its sources include building exterior and interior lighting, advertising, commercial properties, offices, factories, streetlights, and illuminated sporting venues.
For billions of years, life on Earth existed in a rhythm of light and dark that was created solely by the illumination of the sun, moon and stars. Now artificial lights overpower darkness, and our cities glow at night, disrupting the natural day-night pattern and altering the delicate balance of our environment. The negative effects created by the loss of this natural resource might seem unrelatable, but a growing body of evidence links the brightening night sky directly to measurable negative impacts, including: increasing energy consumption; disrupting the ecosystem and wildlife; harming human health; affecting crime and safety.
The light bulb is arguably the most significant invention in our world, but as National Geographic explains, “If light bulbs have a dark side, it’s that they have stolen the night. The excess light we dump into our environments is endangering ecosystems by harming animals whose life cycles depend on dark. We’re endangering ourselves by altering the biochemical rhythms that normally ebb and flow with natural light levels. And in a primal sense, we’ve lost our connection to nighttime skies, the tapestries into which our ancestors wove their star-studded stories, timed the planning and harvesting of cro[s. And deduced the physical laws governing the cosmos.”
Certainly, the need to illuminate everything all the time is a product of our fast-paced and bulging lifestyles. As we all know, we should slow down and, in this case, enjoy the darkness of the sky above our heads and the stillness and restorative effect it provides each day. Farmers did it best — wake to the sun and slow down and rest when it gets dark.
Near bright cities like Las Vegas, traces of artificial light pollution in the sky directly overhead persist from the city center out to over 40 miles away!streetlights are intended to illuminate the street below, but their light is poorly directed, causing undesirable brightness and increasing light pollution.
According to National Geographic, in 2016, scientists estimated that 99 percent of the continental United States and Europe experience some amount of light pollution. Based on observations from the Suomi NPP satellite, a third of humankind cannot see the Milky Way, including nearly 80 percent of North Americans. A team of researchers conducted a study over four years and determined the Earth’s artificially illuminated area had grown by 2.2 percent per year, a rate that does not appear to be slowing.
The adverse effects of light pollution extends well beyond astronomy, according to darkskiesawareness.org, the new research suggests that light at night may interfere with normal circadian rhythms — the 24-hour cycle of day and night that humans have used to maintain health and regulate their activities for thousands of years. Light trespass, occurring when streetlights or a neighbor’s security light directs unwanted lighting onto our property or into our homes, contributes to a loss of natural darkness.
Wildlife, too, is harmed by the unnecessary brightening of the night. From newly-hatched sea turtles to migrating birds, fish, frogs, salamanders, and lightning bugs, artificial night lighting disrupts the cycles of nocturnal creatures in potentially devastating ways. While research is still ongoing, it is becoming apparent that both bright days and dark nights are necessary to maintain healthy hormone productions, cell function, and brain activity, as well as normal feeding, mating, and migratory behavior for many species, including humans.
Time.org states, “Nature is paying a price. One 2017 study found that artificial lighting near waterways draws insects up from the water surface and toward the lighting source, disrupting food chains and weakening the local ecosystem. Another study this year found and equally direct cause and effect between increased lighting over beach areas and a dramatic decline in sea turtle populations, as the hatchlings are lured away from the water and toward the light, where they are snapped up by predators. Migrating birds, which navigate partly by light from the moon and the stars, can be thrown off course when light pollution washes out of the sky. Vegetation is affected, too. A 2016 study showed that trees are increasingly blooming out of season, as lighting coaxes their buds to burst too soon, leaving them vulnerable to damage by cold temperatures before the true onset of spring. That could affect fruit orchards and crops, as well. Not to mention, the disruption to insects’ cycles can affect pollination.
Finally, of course, there is the effect on us. The American Medical Association warns that nighttime lighting, especially the blue-white LED variety, ’is associated with reduced sleep times, dissatisfaction with sleep quality, excessive sleepiness, impaired daytime functioning and obesity.’ Alarmingly, a Harvard study showed that artificial lighting may actually be linked to increased breast cancer rates, probably a result of decreased levels of the hormone melatonin, which affects circadian rhythms.”
Light pollution wastes money and energy. Billions of dollars are spent on unnecessary lighting every year in the United States alone, with an estimated $1.7 billion going directly into the nighttime sky via unshielded outdoor lights. Wasted lighting in the U.S. releases 38 million tons of carbon dioxide into the atmosphere annually; unshielded outdoor lights are directly responsible for 1.2 million tons of carbon dioxide waste. Simply reducing and removing unnecessary lighting saves money and energy, often at minimal expense. Over-lighting the night neither improves visibility nor increases nighttime safety, utility, security, or ambiance.
Light pollution affects every citizen. Fortunately, concern about light pollution is rising dramatically. A growing number of scientists, homeowners, environmental groups and civic leaders are taking action to restore natural light. The good news is that light pollution is reversible and each one of us can make a difference locally, nationally and internationally.
Just being aware that light pollution is a problem is not enough — you need to take steps to do your part. You can start by minimizing the light from your own home at night. Follow these simple steps: only use lighting when and where it’s needed. If safety is a concern, install motion detector lights and timers. Properly shield all outdoor lights (directing light where it is needed and eliminating light trespass and glare) and educate yourself through research. Mention light pollution to your neighbors, coworkers and even your town government. It’s likely you’ll educate people and possibly encourage your town to pass laws reducing light pollution.
For most of Earth’s history, our spectacular universe of stars and galaxies has been visible in the darkness of the night sky. From our earliest beginnings, the dark sky has inspired questions about our universe and our relation to it. The history of scientific discovery, art, literature, astronomy, navigation, exploration, philosophy and curiosity would be dramatically diminished without our view of the stars and dark sky. Let’s work to restore it. You can only see the stars when it’s dark.