Global light pollution is steadily rising each year, study reports

New research shows that light pollution continues to grow in all areas of the world.

Joseph Scalise | Nov 27, 2017

A group of scientists fromthe GFZ German Research Center for Geosciences have discovered that light pollution is higher than ever, and it shows no signs of slowing down.

In their research, the scientists discovered that Earth's artificially lit nighttime surface is steadily growing in both size and brightness across most countries.

From 2012 to 2016, artificially lit outdoor areas grew by 2.2 percent per year. In addition, some 79 nations -- mainly in South America, Asia, and Africa -- saw a growth in nighttime brightness during those years. In contrast, only 16 witnessed a decrease in light during that time, and 39 stayed about the same.

Increases in nighttime light pollution occurred on all different continents, but some of the largest increases came in previously unlit regions. That means the fastest rates of increase tend to occur in places that had not been strongly affected by light pollution in the past.

Researchers made this discovery by using images from one of the USA's polar-orbiting satellites to track the changes in nighttime light over time. They then compared images from October 2012 with those from October 2016.

While researchers initially believed energy efficient lighting would decrease global light usage, that has not been the case. Rather, it appears the use of artificial lighting is expanding rapidly, regardless of the technologies used.

This is a large issue because nighttime light affects ecosystems across the world. It has many ecological and evolutionary implications for a wide range of organisms, and may reshape entire social ecological systems. The extra light affects humans as well.

"Artificial light is an environmental pollutant that threatens nocturnal animals and affects plants and microorganisms," the researchers wrote in their study, according to USA Today.

While there is no set plan to combat rising light pollution, the team in the study has a few ideas. They believe avoiding glaring lamps and using more efficient ways to illuminate places like parking lots or city streets could go a long way. This is because dim, closely spaced lights tend to provide better visibility than bright lights that are more spread out.

"In city centers, we need to completely rethink the way we light by putting people at the center and not cars, which have their own lights," said lead author Christopher Kyba, the GFZ German Research Center for Geosciences, according to CNN. "We shouldn't have streetlights anymore. We should have lighting for pedestrians and for the people riding bikes."

The new study is published in the journal Science Advances