This semester, I have been researching light. More specifically, artificial light - a rising concern among biologists, astronomers and environmentalists. The general population is unaware of how artificial light can adversely affect their health, the ecosystems of nocturnal species and the Earth's atmosphere. My interest in this topic began during an off-the-grid artist retreat at Fancyland in the Cascade mountains. There was no electricity and the nearest town was a thirty minute drive away. (I got really good at using oil lamps that week!) This experience made me aware our natural day/night cycles. In this post, I'd like to address some definitions and issues, light pollution in Arizona, and some action steps. My intention is not to leave any of you feeling disempowered, but rather, informed with choices and a new sense of appreciation for the dark. So, let's go!
What is light pollution?
Light pollution refers to the adverse effects of excessive artificial light at night (SciShow). There are three types of light pollution: light trespass, skyglow, and glare. Light trespass occurs when light is directed in an unwanted area. (For example, a street light leaking into your bedroom window.) Skyglow refers to the light hovering above cities at night, caused by excessive lights that are partially directed upwards. Glare is caused by bright lights shining horizontally, like car headlights or floodlights.
How does light work?
Light is both a particle and an electromagnetic wave moving at a fixed speed. There are wavelengths of light that we can see, and many that we cannot see. The farther on the red end of the spectrum, the longer the wave-lengths. They require less energy. The farther on the violet end of the spectrum, the shorter the wave-lengths are. They require much more energy. Our eyes and bodies are adapted to light that we can see, somewhere in the middle of the spectrum. The video below makes an interesting point about all the other invisible electromagnetic waves we're exposed to, including radio, gps, and wi-fi - around 6 minutes in.
Light and Biorhythms
The most obvious way that light alters human biological rhythms is in our sleep patterns. The pineal gland is a part of our brain that secretes melatonin, and will only release it in the absence of light. This hormone is released to naturally repair our cells as we sleep, and much research has found it to help destroy cancer-causing free radicals in the body (4yourhealth100). Have you ever looked at your cell phone in the middle of the night after you wake up, just to find that you can't fall back asleep? Bright, artificial light has the same effect as the sun, sending a message to your brain that it's time to wake up.
Light and ecosystems
Many forms of life are affected by constant lighting and eventually alter ecosystems. Changing migration patterns, mating habits and sleep cycles are all hurting animals. Birds, for example, instinctually migrate using celestial navigation. Many birds die because they fly around a brightly light building or tower, and simply collapse from sheer exhaustion. Sea turtle hatchlings also instinctively follow the moonlight to find the shore from the beach, but instead are following the lights of coastal cities. Because of this, they're now an endangered species. For more information about various species affected by light pollution, visit http://physics.fau.edu/observatory/lightpol-environ.html.
Light pollution in Arizona
The topic of night light is very relevant to the state of Arizona. Tuscon is home to the International Dark Sky Assosiation, arguably the most important organization fighting light pollution today. They also dedicated Flagstaff as the first internatial dark sky city (watch the video below if you're more interested in learning more.) As light began leaking into the beautiful Grand Canyon sky at night, more action steps were taken. If only Phoenix would catch on!
Apparently one can see the skyglow of Phoenix all the way from the Lowell Observatory in Flagstaff...
What can I do?
I know it's pretty hard to control light exposure, especially when you live in a city that never sleeps and school/work requires you to look at a digital screen for hours on end. The good news is that the more you make conscious decisions on light, the more money you save, more stars you'll see, deeper sleep you'll have, plus Mother Nature will thank you.
Here are some realistic steps you can take:
1. Have a space appreciation day. Go to a national park (like Oracle near Tuscon) or an observatory (like Lowell Observatory in Flagstaff.) Seeing the thousands of stars and the milky way will help you appreciate the natural beauty of the night sky.
2. Close your blinds and curtains after sundown. Not only does this reduce light pollution from lamps, TVs, etc., but reduces outside light pollution and increases your chance of having a good night's sleep.
3. Don't stare at your cell phone or TV before falling asleep. Your body is conditioned to wind down after the sun goes down. Limit light exposure slowly from sundown till bedtime.
4. Always turn off lights when you're not using them. Saves the Earth some CO2, saves you money, reduces light pollution. Bingooo.
5. Install motion detector lights. You can do this in your hallways, but it's especially important outdoors.
6. Direct your light. If you are in control of your outdoor lighting, make sure to aim lights downward and cover them with a shield. Light gets polluted when it scatters upwards into the sky.
7. Use warm lights or candles. Purchase some candles and light bulbs with low wattage that emit warm light. Red light is the least harmful wavelength for your eyes.
8. Do some things only during the daytime. Particularly those things that can't be done without copius amounts of light.
9. Wake up with the sun. Less time you'll be trying to be productive without sunlight!
10. Download a day/night light app for your phone or laptop. I use Flux for my laptop. It's an app that detects the time and adjusts the color of your screen so it's warmer during the morning and night when the sun isn't out. Twilight is another option for phones and tablets. Also, you can enable Night Shift on your iPhone (same idea).
Thank you for reading! I'm excited to hear your responses.
What is light pollution and how does it hurt our planet? (DNews Plus)
How do humans perceive light?
Hidden cost series: light pollution
The strange scourge of light pollution
Flagstaff celebrates lights out
Does light pollution affect birds?
IPads, Computers, and TV Before Bed? - Blue Light, Melatonin and Child Sleep
Blue Lights Affects Us in 3 Ways
Melatonin and the Pineal Gland