And artificial light of unnatural intensity and color is encroaching ever farther into remote wildlands and out over unlit oceans, thanks to skyglow, the diffuse pall created as upward-shining light from towns and cities is scattered by dust, water and gas molecules in the atmosphere. Unlike older-style, orange-glowing lamps, which emit light from a narrow part of the spectrum, the brighter, whiter light-emitting diodes (LEDs) that are fast replacing them emit light across the spectrum, with a peak in the blue region - the most wildlife-unfriendly light of all. That price is set to rise, ecologists warn. While we enjoy the benefits of well-lit homes, towns and cities, artificial illumination is exacting an unexpectedly high price from plants, animals and ecosystems that evolved when days were light, nights were dark and the age-old cycles of illumination were predictable. Now it’s the turn of ecologists, alarmed by the toll on birds, moths and other insects lured to their deaths by animals no longer able to navigate by night foragers afraid to go out at night and by creatures that use light to communicate but are unable to transmit their messages. A third of the world’s population can’t see the Milky Way.Īstronomers and stargazers have long campaigned for a return to darker skies. Some 83 percent of the human population lives under light-polluted skies. In the second half of the twentieth century, the artificially illuminated area of the world grew by up to 6 percent a year, and a 2017 analysis of satellite data shows it’s still expanding by 2.2 percent each year, and getting brighter. The world is steadily losing the deep dark of nighttime.
Kumlien’s report of the daily death toll was the first scientific account of the ecological downside of lighting up the night sky. Birds heading south for winter were drawn in and died as they flew into wires, windows and each other. It was the perfect vantage point to watch for migrating birds, but Kumlien was there for a different reason: Milwaukee’s pride and joy was proving an avian death trap.įrom early evening until almost midnight, the tower was lit up by four electric floodlights, creating a dazzling beacon in an otherwise dark sky. On September 23, 1887, eminent ornithologist Ludwig Kumlien climbed the 60-meter-tall tower adorning Milwaukee’s new architectural landmark, the Industrial Exposition Building.
0 kommentar(er)
