So what if I can’t see the Milky Way at night, it’s just a little light pollution right? Hey there stars, Sapna here for DNews. According to the Atlas of Artificial Night Sky Brightness about 83% of humans on Earth are exposed to night skies that are at least 10% brighter than natural levels, or what the Atlas defines as “light pollution”. When I say pollution you probably think of smog or oil spills or some other substance we put into the environment that really mucks up the place. By comparison then, calling an overabundance of light “pollution” may sound a bit overdramatic. What effect can leaving the light on all night really have on the environment? As it turns out our love of light can mess with both flora and fauna more than you might think. Earth’s ecosystems have spent billions of years adapting to a day-night cycle, but the invention of artificial light and subsequent vanquishing of the darkness is throwing some organisms outta their groove in very profound ways.
Take for instance baby sea turtles. Those little guys hatch on the beach and it’s imperative they get to the water before some predator snatches them up. When they’re born at night they find water by putting the dark and elevated silhouette of land behind them. But lights from houses or roads along the beach can disorient them, making them crawl in the wrong direction until dawn when they’re easy pickin’s. That’s if they even get hatched in the first place: momma turtles that have been returning to the same beach for decades may be discouraged by the brightly lit shore and look for another nesting site, or they could get disoriented themselves and wander into traffic. Light pollution can effect some creatures in the water also. Microscopic animals called zooplankton hang out at lower depths during the day and rise up to feed on algae each night. If the night sky is too bright, they don’t rise up as high or in as great of numbers, so they don’t eat as much algae, which can in turn, contribute to an algal bloom.
Coastal light can also hurt some coral species in the great barrier reef, which rely on phases of the moon to sync their release of sperm and eggs into the water. If the moon’s phases are masked, then they might not spawn at the right time and that means less new coral. Light pollution isn’t great news for some land creatures either. Birds that migrate at night are known to crash into brightly lit towers or skyscrapers, or circle them until they die of exhaustion. Amphibians like salamanders that forage after dusk will wait longer to come out since the night sky is more brightly lit and they don’t get as much food. and get this.. Some frog and toad males will not ribbit if they’re well lit.. so then lady frogs won’t holler back and mate with them. But if you don’t care about the frogs or the salamanders or the birds or the coral or the baby turtles, well you’re heartless but you should still know that light pollution probably affects you too.
First off if you live in a big city like New York City like I do…we can all say goodbye to the stars, unless something knocks the power out like an earthquake did to Los Angeles in 1994. Residents called Griffith Observatory asking why the night sky looked different after the earthquake. They were seeing the Milky Way for the first time. If it’s bright enough to read a book outside at midnight, that’s a sign those bright lights can keep you up by stopping you from producing melatonin. Obviously that can cause sleep disorders, but melatonin is also an antioxidant so it’s possible that light is actually increasing your risk of cancer as well. And of course keeping those lights on requires energy, and if that energy comes from a fossil fuel source, light pollution is causing good old-fashioned regular pollution too. By leaving the light on all night you are literally burning the midnight oil. So if you can help it, stop leaving the light on.
Light pollution can mess with your sleep, but what can regular pollution do to the rest of you? Julia Covers that right here. Have you noticed the effects of light pollution in your life? Let us know in the comments below, and don’t forget to like and subscribe for more DNews every day..