See How an effort to reduce fossil fuel use led to another environmental problem: light pollution by Sumeet Kulkarni of The Los Angeles Times. This could also be in the category of "life is full of tradeoffs" since we cut fossil fuel use but get more light pollution.
Excerpts:
"In 2014, Los Angeles cut its annual carbon emissions by 43% and saved $9 million in energy costs by replacing the bulbs in more than half of the city's street lamps with light-emitting diodes.
That year, the Nobel Prize in physics went to three scientists whose work made those LEDs possible. "As about one fourth of world electricity consumption is used for lighting purposes, the LEDs contribute to saving the Earth’s resources," the Nobel committee explained when it announced the award.
For more than a century, most sources of artificial light wasted energy in the form of heat. LEDs are much more efficient, requiring less than 25% of the energy consumed by an incandescent lamp. By 2020, LEDs accounted for 51% of global lighting sales, up from just 1% in 2010, according to the International Energy Agency, an intergovernmental organization that analyzes global energy data.
It sounds like a clear win for the environment. But that's not how Ruskin Hartley sees it.
“The drive for efficient fixtures has come at the expense of a rapid increase in light pollution,” he said.
Hartley would know. He's the executive director of the International Dark-Sky Assn., or IDA, and he's one of a growing number of people who say the dark sky is an undervalued and underappreciated natural resource. Its loss has detrimental consequences for wildlife and human health.
And yet the public's embrace of LEDs keeps rising, spilling way too much light into the sky where no one needs it.
"We've taken a lot of the energy savings and just lit additional places," Hartley said. It's a classic example of the Jevons paradox, in which efficiency gains (such as better automobile gas mileage) are countered by an increase in consumption (people driving more often).
In essence, Hartley and others say, we've traded one kind of pollution for another.
That's not the only problem. In addition to making more light, LEDs have altered its fundamental nature.
The light produced by incandescent bulbs had warmer amber or yellow colors, "more in tune with firelight, the only light aside from starlight we knew," said Robert Meadows, a scientist with the Natural Sounds and Night Skies Division of the National Park Service. LEDs, in contrast, give off cooler bluish-white tones that exacerbate light pollution for the same reason that the sky is blue.
Sunlight contains the full spectrum of colors, and air molecules happen to be the right size to scatter the shorter blue wavelengths more effectively than any other. This causes blue light to spread more readily in the atmosphere, giving the daytime sky its familiar color.
After the sun goes down, the same thing happens with LED light that spills wastefully into the sky: It gets diffused to a greater extent and increases "sky glow," the combined radiance of city lights.
Travis Longcore, an urban ecologist at UCLA, estimates that artificial lighting causes the night sky in Los Angeles to shine 1½ times brighter than a night lit by a full moon. All creatures are affected by the brighter nightscapes, especially those who cannot close the blinds for a sound sleep."
"Humans, too, are vulnerable to light pollution. Artificial light blocks the production of melatonin, a hormone that regulates sleep cycles, and disrupted sleep cycles have been linked to an array of health problems. The American Medical Assn. warned in 2016 that high-intensity, blue-rich LED lights were “associated with reduced sleep times, dissatisfaction with sleep quality, excessive sleepiness, impaired daytime functioning, and obesity.”"
"Nineteen states, the District of Columbia and Puerto Rico have laws on the books to prevent light pollution. Arizona, home to several large telescopes, requires all exterior lights to be fitted with shields that prevent light from escaping skyward. Some coastal areas in Florida mandate low-power amber lights that won't draw sea turtle hatchlings away from the safety of the Gulf of Mexico."
Related post:
The Jevons paradox and the limits of data storage
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