Why #LightPollution is a solvable #environmental crisis

Excessive #OutdoorLighting is deadly to #animals and takes a toll on #HumanHealth and wellbeing, too. But when it comes to large-scale environmental problems, this one may be a relatively easy fix.

By Alissa Greenberg
Friday, April 1, 2022

"In recent decades, lightbulbs made with #LEDs arrived, a revolution in energy efficiency with seemingly little downside. After all, an #LED bulb converts some 90% of the electricity it uses into light, whereas a conventional incandescent bulb only converts about 10%. And LED bulbs are touted as lasting up to 25 times longer.

"But the physics of LEDs make them fundamentally different from incandescents. While those traditional bulbs put out warm white light made of all colors mixed together, LEDs filter blue-rich light through a specialized phosphor material, producing light that appears white to the human eye but is still more blue-intense than incandescents’ light.

"But #BlueLight is also the most disruptive to our #nighttime environment because it mimics daylight, disrupting the hormone production and sleep cycles of both animals and humans.

"#Melatonin, one of those hormones, helps the immune system destroy renegade cells dividing out of control. That can lead to other health issues, including heightened rates of #cancer. And, 'we’re not the only ones who produce melatonin,' says Mario Motta, a cardiologist and trustee of the American Medical Association. Even amoebae produce melatonin'—meaning even amoebae might be vulnerable to light at night.

"The impacts of light pollution are evident everywhere from human health to astronomy research, but they come into particular focus in the recent phenomenon of global species #dieoffs. Between 100 million and a billion birds die every year due to light pollution, according to Massachusetts IDA chapter president James Lowenthal. New York City recently dealt with a huge die-off, 'with flocks of #MigratoryBirds slamming into buildings,' says Sarah Bois, an ecologist at the island’s Linda Loring Nature Foundation and a member of Nantucket Lights. 'They’re attracted to light.' A 2015 study at New York’s 9/11 'Tribute in Light'' installation showed an increase from 500 birds within half a kilometer of the light beams before they were turned on to 15,700 just minutes after.

"The issue is a double whammy for birds because they rely on #insects for food—and those populations are plummeting, with light pollution contributing significantly to the so-called "#InsectApocalypse.” By some estimates, one third of insects attracted to light sources at night die before morning, either due to exhaustion or because they get eaten. And according to a study in Germany, the number of insects in that country alone that die after being attracted to lights can number 100 billion or more in a single summer.

"Some starve to death searching for food that should appear bluer at twilight but is lit up amber under streetlights, says insect conservationist Avalon Owens, a doctoral candidate at Tufts University. Some are thrown off by light just the way we are, because of their #CircadianRhythms. #Pollinators whose schedules are altered by artificial light miss the #flowers they’re evolutionarily paired with, if the flowers naturally close and open with the warmth of the sun. And insects that rely on circadian rhythms for their yearly development don’t hibernate in time for winter and freeze to death.

"On #Nantucket, these phenomena are of particular concern because the island is home to a remarkably healthy population of northern long-eared #bats, which are endangered. Like many birds, the bats rely on insects for food and are easily dazzled by light, putting them in increasing jeopardy. Jack Dubinsky, director of the Maria Mitchell Aquarium on Nantucket, says he’s concerned that adding increasingly lit-up nights to the challenges of #ClimateChange, water quality, and #ecosystem collapse could put huge pressure on some already struggling species. 'The more curveballs we throw, the less likely they’ll be able to find their way,' he says.

Read more:
https://www.pbs.org/wgbh/nova/article/light-pollution-led-nantucket-solutions/