Blinded by the light: The solvable environmental issue you’ve been waiting for

By Jennifer Knoch

One of the most striking things about spending time in the country is the stars. Those swirling galaxies, a sky more freckled than my summer skin. Something glorious can be revealed simply by remembering to look up.

We’re seeing the same constellations that are above us in the city, just no longer hidden by so much competing light. There’s a metaphor here, about all the things our progress obscures, but today we’ll be focusing on the practical: all the creatures blinded by the light.

83% of people around the world are living under light polluted skies, including 99% of Americans, and in some cities 99.5% of the stars are invisible. And according to a 2017 study, light pollution is increasing by 2% a year.

Why is this a problem? It’s not directly warming the planet or harming human health like so many other emissions, but it still has an indirect impact on us by hurting the ecosystems that support life on this blue marble. Remember that life evolved before electric light, and now it messes with the internal rhythms of all creatures great and small, slowing reproduction rates, causing birds to fly into buildings, or drawing migrations off course. Artificial light harms a huge range of species, from corals to bats to primates. For example, newborn sea turtles use the moon to guide them on their treacherous path to the ocean, but with all the competing light sources, they can get discombobulated long enough to be gobbled up by their many predators.

And while it’s adorable to consider a wallaby wearing blue-light glasses, there’s an easier solution: dim the lights. Excess light is something that can literally be switched off to stop its negative effects. Instant gratification like this is hard to come by in the environmental space, so let’s learn how we can dim the lights for a brighter future.

At home

If you have external lights (and control over them), first assess whether they’re necessary. If so, replace them with a warm-coloured LED on a motion sensor. Warm wavelengths scatter less intense light, so choose a bulb rated under 3000 kelvins. Choose a light with a shield (a shade that focuses the light downward) around the bulb, so the light goes just where it’s needed. Shielding matters: according to the International Dark-Sky Association (IDA), 20 to 50% of outdoor residential lighting is wasted from poor shielding. You can also look for a fixture certified by the IDA.

The bonus to all this? You’ll save money and lower your carbon emissions. Bad outdoor lighting wastes enough energy every night to power a 50-inch plasma TV for an hour

At work

If your work isn’t your home, and there’s no one in the building overnight, kill the lightsespecially if you work in an office tower. This is doubly important during migration season, which is underway now. Every year, tens of thousands of birds collide with buildings in Toronto alone, and many more are drawn off course, because they usually migrate by the light of the stars.

(By the way, in daylight hours, you can also use tactics like window stickers to prevent bird collisions. There’s a ton of info on effective interventions at

On a municipal level

Of course there are lots of big interventions that require many council meetings and more patience, but cities like Brampton, Mississauga, and Markham are all upgrading their streetlights. Manitoba is making province-wide upgrades to 130,000 streetlights, preventing 27,000 tonnes of greenhouse gases annually (roughly the energy used by 2,200 homes). Toronto, sadly, is tackling this much more slowly.

But it’s not as easy as changing a lightbulb: we still need shields on street lights that shine just where needed, warmer light, and fixtures that are a bit closer to the ground. The effect isn’t only safer for wildlife, it’s safer for humans too. Glare from poorly considered lights can actually cause accidents and is generally unpleasant. Think less institutional glare, more hygge glow.

Now you might say, what about crime? As a woman, light makes me feel safer when I’m going anywhere alone at night. But according to the IDA, several studies suggest that lights don’t actually prevent crime. In fact, brightly lit alleyways in Chicago correlated with increased crime. No one’s advocating for getting rid of lights anyway, just using the lights we have in a way that’s safer and more effective.

If this gets you all lit up like a 60-watt bulb, the IDA has info on how to advocate for better lighting ordinances where you live.