On January 17th, 2019 Philips Lighting held a webinar covering the ecological and human effects of light pollution. Two keynote speakers presented their research and findings. This is my own summary and thoughts on this webinar and the information presented.
The presentation was basic but provided a good overview of the problem and some of the impacts to people and wildlife. There were a number of key takeaways which I feel important for considering when it comes to new projects/developments (more light being added to our environment) and how we use/implement light at night as well as UDM updates. I hope everyone gleaned something useful from it.
Points to highlight:
- Light at night is not natural – hence why it’s called artificial light.
- The natural nighttime environment is increasingly polluted by artificial light. LEDs are making this worse. (research/NOAA-VIIRS satellite data).
- Several studies have linked artificial light at night to negative impacts on human health. In free-living animals, light pollution is associated with changes in circadian, reproductive, social behavior and physiology of species, which includes changes in the daily timing of activity.
- Light at night can create imbalances; isolate or attract, reduce species population. And shown to create nocturnal and diurnal species competition where none existed previous.
- Lights should always be down directed (shielded) and not point up into the sky. Dimming is helpful over night, reduces pollution and energy waste. (lights up or unshielded wallpacks and wall washing are still big problems within the city)
- White light (rich in blue) attracts more insects and more disruptive (mayflies were an example but not limited to. Mosquitoes are another example more attracted to higher kelvin, white light and light pollution has been connected in medical research to increase of west nile virus in humans)
- Lux levels should be targeted to the minimum possible not the highest. Even 10 lux of artificial light can have adverse impacts on species, including humans. So we should be mindful of not over-lighting. ( In many developments/projects/retrofits light levels are far to high and it’s not needed. The human eye is very responsive and adaptable when glare and intensity are not over-powering, and if using properly shielded fixtures. Over lighting leads to light pollution and is light waste and energy waste which are associated with climate change. )
- No higher than 3000K and lower is better even. (There are a number of manufacturers now producing 1750K – 2500K LED that are near or on par efficacy to now dinosaur 4000K and 5000K versions)
- Choosing the right spectrum of light is important. (Example, artificial light mimicking daylight within or near residential area would be disruptive to people’s health and urban eco systems. Adding white light near natural areas is disruptive as well and we find this happening with urban sprawl. As we add more homes, more stores and more lights. White light is not safer nor are brighter lights. White light may be more aesthetically pleasing to humans, but it is far worse for the night environment and wildlife where pollution is concerned)
- Bylaws/ regulation / city urban design manual updates can help reduce light pollution and provide a positive framework for both developers and residents to better understand and mitigate their pollution contribution.