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How can we reduce light pollution?

Light pollution is preventable! There are a lot of things you can do to reduce your impact. You
can also help reduce the impact of your community. First, you can turn off your lights at night,
or close the curtains. Indoor light can cause glare outdoors. Then look at the lights outside your house.
Can they be turned off? Or can motion sensors be installed so they only come on when needed? Glare
from outdoor lighting can be reduced by shielding light fixtures. You can talk to friends, family, and
guardians about making some of these changes at home!
LED lights are often used outdoors. But LEDs can harm humans and animals. Their high-energy blue
light reaches far into the eye. This over-stimulates photoreceptors and can lead to vision loss. It’s safer
to use lights and filters that are coloured red or yellow.

Source: https://www.shutterstock.com/el/

Fun facts (or maybe not) about Light Pollution!

1. The sky glow of Los Angeles is visible from an airplane 200 miles away. Residents of L.A.
haven’t been able to see the stars for a while. In fact some city dwellers don’t even know what
a natural night sky looks like.
2. Artificial light at night disrupts the seasonal cycle of trees. Even plants depend on the natural
cycle of day and night. Artificial light at night can throw off a plant’s response to the change of
seasons.
3. Light Pollution unnecessarily contributes to climate change. In an average year in the U.S.,
outdoor lighting uses some 120 terawatt-hours of energy, mostly to illuminate streets and
parking lots. That adds up to $3.3 billion and the release of 21 million tons of CO2 per year! To
offset all that CO2, we’d have to plant 875 million trees annually.
4. Light pollution kills millions of birds a year. Artificial lights can disrupt the migratory schedules
of birds causing them to leave too early or too late in the season, missing ideal conditions for
nesting.
5. Exposure to artificial light at night puts your health at risk. Humans evolved with the rhythms
of the natural light-dark cycle of day and night. Due to artificial light, most of us no longer
experience truly dark nights.

This project has been funded with support from the European Commission. This communication reflects the
views only of the author, and the Commission cannot be held responsible for any use which may be made of the

information contained therein.
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