15 Dec 2011

In Praise of Darkness

photo credit: Luis Argerich/Flickr

1/23/12 UPDATE: Now a new documentary, The City Dark, looks into the science on environmental and health effects associated with lighting up our cities and suburbs. With a rack of awards already received, The City Dark may well be set to spark a nation-wide conversation. To find out if it’s showing near you, check out the list of screenings.

December is a time of darkness–black tree trunks, grey skies, black water in ponds at dusk–as we descend into the deep midwinter and the solstice.

Much of the earth’s animal life has gone into this darkness. Frogs have buried deep in the mud or at the bottom of icy ponds; beavers have hunkered down in their lodges with sticks and mud to keep out what light there is. Bears have found dens; raccoons, skunks, and woodchucks have burrowed down for the months to come.

This time of rest and solitude is a part of these animals’ natural cycle. For millennia humans outside the tropics also lived surrounded by darkness in the deep mid-winter. They only had small fires to light and warm their winter world. Darkness pulled people close to keep warm, mend things, and sing or tell stories by the fire.

Now we break the darkness with bright seasonal, illuminations: Hanukkah candles, colorful string lights on our homes, and brilliantly decorated Christmas trees. We have music celebrations and exuberant parties filled with activity, noise, elaborate food, and drink. Our naturally dark world is ablaze with light and activity.

These seasonal celebratory lights, however, are a small part of the lights our communities have installed everywhere. Flying over much of America at night one realizes how little darkness there is in substantial stretches of our country. And some would make it even worse. As David Brooks noted in a recent column, Newt Gingrich (in his book Window of Opportunity) has spoken approvingly of the idea of “a mirror system in space [that] could provide the light equivalent of many full moons so that there would be no need for nighttime lighting of the highways.”As Scott Denning, an atmospheric science professor at Colorado State University, was quoted in Politifact: “Imagine having a really annoying neighbor who beams sodium vapor lamps into your bedroom windows. Now imagine everyone in the world having such a neighbor.”

This isn’t just a concern for anyone who wants to see the stars. Lighting up our night sky tears at the fabric of the ecological web. Night-flying birds crash into brightly-lit buildings by their millions every year, as Alan Burdick points out in OnEarth. Just last week, 1,500 eared grebes died when a night-flying migratory flock tried to land in a Wal-Mart parking lot in Cedar City, Utah, mistaking the gleam of puddled water under the lighting for the surface of a lake. Moths and other insects that hover around outdoor lights provide a feast for bats, but one that within a couple of years can dry up as their predators finish them off, killing off key pollinators, and leaving the bats and others with nothing on which to survive.

When we walk outside our homes we’re surrounded by glare from neighbors’ houses, street lights, passing traffic, or the 24-hour glow of businesses. Even away from suburbs or cities, we have ambient night light in most places. I have read that 70 percent of Americans have never seen the Milky Way, not because they haven’t been outside at night, but because ambient light dims the view of our own galaxy.

Environmentalists often talk about changing light bulbs to change the world. It sounds like a small thing, but it has sparked a controversy in the ongoing political debates and it is something we, as individuals, can do. But we can also turn off some lights in our homes and in our communities. The International Dark-Sky Association is dedicated to this very effort.

I am lucky because we live in the Catskill State Park that has miles and miles of “forever wild” land. The darkest place in New York State is in these mountains: The Pepacton Reservoir, part of the water supply for New York City. Standing out on a hillside by this water, the darkness reveals the universe above us. Each star, each constellation, the broad sweep of the Milky Way has a clarity and depth that is profound. Far from blinding us, the darkness provides a glimpse of how much lies in the infinite depths we inhabit.

So when I go back to civilization, I always ask, “What do these lights conceal?” Lights that burn all night in shopping malls and parking lots, flood lights in yards, excessive street lighting–don’t they just trap us in their narrow circles? If we allow our eyes to adapt, the rods on our retinas can pick up the faintest distinctions in light and dark.

The dark of December isn’t permanent. In the Catskills, we’ll soon get snow and ice that catch the light. For this brief spell we can enjoy the darkness on the way to the white and sparkling clarity of the new year.