Don't shed some light on it

·3 min read

Jan. 23—It's hard to escape noise.

Those of us who live in towns and cities hear traffic sounds and the whirring of distant industries. It would seem that with our tall bluffs, being high atop Mankato and North Mankato would bring quiet solitude. But if you're on a bluff, the rumble of highway and rail traffic or humming of CHS or ADM funnels up clearly.

Even on the farm we had our own noise pollution — the blast of corn dryers in the fall and lids of hog feeders dropping as pigs fed.

While our minds block out regular noises, sound pollution is bad for human health and for some animals. Surprisingly, it even affects plants and trees. Studies have shown that in higher-noise areas there is far less diversity of plants and trees, likely because the noise drives away songbirds that would deposit a variety of seeds.

Light pollution is often more subtle but we have a lot of it in our lives, wherever we live.

It can mess with our circadian rhythms and melatonin levels, contributing to sleep disorders.

We're so conditioned to noise and light that it's jolting when there is none. Whenever we go to our cabin, a mile from any country highway with no yard or street lights anywhere around our bay, the absolute night darkness and quiet beyond the occasional barred owl chatter is both wonderful and a bit disconcerting.

While the bright outdoor light pollution is most noticeable, we have a lot of it in our homes. Even in the dark, TV and lights off, I see small lights in every room — the DVR, TV desktop box, computers, printers, appliances, clocks, power cords.

Light pollution outdoors has gotten a lot more attention in recent years, with more groups and governments paying attention. Many cities, including in this area, have included lighting design standards into their zoning rules to help limit the problem.

Improper street lighting can disorient drivers. Too much light pointing skyward creates nightmares for scientists trying to scan the skies with telescopes.

Even with the naked eye, we don't see stars as well. Years ago a guy wrote a question to the genius Parade magazine columnist Marilyn vos Savant that at first blush seemed stupid: "Where did all the stars go? In the '50s, the sky was loaded with them."

Many stars did, effectively, go away, as light pollution keeps us from seeing the spectacular starry night sky people could enjoy several decades ago.

While we rightly view light — from fire to electric lights — as having improved and safeguarded our lives dramatically, we realize you can have too much of a good thing. Worldwide 80% of people live under artificial light and 99% of Americans can't experience a natural night without traveling to a very isolated spot.

The International Dark-Sky Association works to reduce light pollution around the globe, often focusing on the big things like ensuring street lights and other big outdoor lighting is focused downward.

In Australia, efforts to curb light pollution are taken seriously because lights cause problems for their abundant wildlife.

Baby marine turtles use the relative brightness of the horizon to guide them to the ocean. But when artificial lights outshine the moon and the sea, the hatchlings become disorientated and often die. It also leaves other animals with a variety of migration, eating and sleep problems.

Australia has national guidelines we could all use to make a small impact. Start with natural darkness and only add light for a specific purpose; use smart light controls to shut off outdoor lights when they're not needed; point lighting downward, shielding the top; use the lowest intensity lights necessary indoors and out; and even painting buildings a darker color helps as shiny or light-colored surfaces reflect light into the sky.

Most are easy enough to do. We'll all sleep better if we do.

Tim Krohn can be contacted at or 507-720-1300.