Light pollution boosts air pollution

I’ve written about light pollution and its effects in the past; but here’s a new impact that has recently been discovered – lighting up the night sky can actually boost air pollution it seems.

At a recent American Geophysical Union meeting, Harald Stark, a research scientist from the NOAA Earth System Research Laboratory, presented findings that indicate that our night time lighting is influencing chemical reactions in the atmosphere and affecting concentrations of some airborne pollutants.

According to a related press release from the International Dark Sky Association (pdf); at night, chemicals from car exhaust and other anthropogenic (human) sources are broken down by something called nitrate radicals. Naturally occurring, these form only at night as sunlight destroys them.
While city lights may be far less brighter than sunlight, it seems they are bright enough to also affect levels of nitrate radicals and consequently slow down the night-time cleansing of our air by up to 7%; which is quite considerable. Additionally, the starting chemicals for ozone pollution the next day can be boosted up to 5%.
So, this gives an even more compelling reason for decreasing light pollution, specifically up-light. It isn’t just about helping animals find their way or warm and fuzzy stuff like being actually able to see the stars (which I feel is actually very important) – it can also improve the quality of the air we – and every other creature – breathes.

Isn’t it amazing (and rather frightening) the impact we have and how we’re still really only just scratching the surface in regard to learning about the the knock-on effects of our activities.

Learn more about light pollution.