Access to the Aurora australis is a compelling reason to protect our nightscape, but there are many others just as important that also need to be acknowledged.
If we light our city smartly with care and consideration, Dunedin can sparkle with stars, radiate welcoming warmth, thrive with success, and be a progressive, guiding light of inspiration to the rest of the globe - as the first internationally recognised Night Sky City in the southern hemisphere.
This special status will provide numerous economic, social and cultural benefits, including enhancing our reputation as the wildlife capital of New Zealand, boosting dark sky tourism in the South Island, and further distinguishing us as a must-see destination.
Although there’s great support for this visionary endeavour, if the DCC installs white LEDs (3000K-4100K) all will be lost.
To protect residents, wildlife, the environment and our precious night sky, the Dunedin City Council must install energy efficient Phosphor Coated (PC) Amber LED (2200K) streetlights OR postpone the blue-rich white LED streetlight retrofit indefinitely and fully shield and re-position the existing orange High-Pressure Sodium (HPS) streetlights.
WHITE LEDS NOT SO SMART
Despite mounting scientific evidence, and much public outcry against white LED streetlights, (too bright, too harsh, too clinical), municipalities are prioritising energy, maintenance, and operational savings, above the greater long-term health, ecological and environmental costs which outweigh them.
The New Zealand Transport Agency (NZTA), who sets guidelines for road lighting and design, and co-funds the changeover, has also not considered the full range of risks. (All approved lights on their current M-30 list are high-intensity white LEDs between 3900K-4100K.)
As alternatives have not yet been looked at, and pressure to save resources builds, ironically, decision makers are prevented from illuminating their communities safely and well.
HEALTH & SAFETY
Artificial light at night (ALAN) has dire consequences on wildlife because it impairs biological processes required for health, while also disrupting communication habits, foraging, mating and orientation.
The brighter the light the worse its effects, and white LEDs are exceptionally bright due to the blue and green wavelengths of light they emit. As these wavelengths mimic sunlight, white blue-rich LEDs at night trick organisms into thinking it’s daytime.
In 2014, General Electric published a white paper on the problems with “blue-rich” LED lighting. Then in 2016, the American Medical Association published a damning report unanimously supporting the avoidance of blue-rich LEDs.
The implications are serious and far reaching because LED lighting will soon be unbiquitous. Although people can reduce their exposure to blue-rich light in their own homes, it’s impossible to do so outdoors with white LED street lighting.
It’s imperative we protect our city and the rich biodiversity upon which our ecotourism depends. This includes the Otago Peninsula - home to our valued albatross, seal, sea lion, yellow-eyed and little blue penguin colonies, and the Orokonui Ecosanctuary on the mainland - home to endangered and protected native species such as the takahe, tuatara and our beloved nocturnal kiwi.
Exposure to blue-rich light at night also suppresses the production of melatonin (a powerful antioxidant with protective immune, anti-inflammatory, and tumour suppressing activity). For humans, this means an increased risk of Alzheimer’s, cancer, diabetes, depression, obesity and other diseases.
Not only that, blue wavelengths of light scatter in the eye to create a “veiling” effect, which causes visual discomfort and dangerous disability glare. (The blue component is perceived as being 3-5 times more glary than orange light - as seen with the blinding headlights on modern cars.)
For young people, mature drivers (a large percentage of the population), and those with impaired vision, white blue-rich LEDs pose an even greater risk. These lights also cause significantly more contrast, which diminishes night-time vision as well.
Even when shielded (and at the same lumen output as the HPS lights they replace, white blue-rich LEDs significantly worsen light pollution because their light is brighter, travels further, and when directed at the ground, bounces off surfaces back into the atmosphere.
A worldwide increase in light pollution from white blue-rich LED streetlights has been documented by the International Space Station, and is currently being monitored due to concerns about its widespread impact. http://www.techinsider.io/astronaut-photos-light-polution-led
The intense light from white blue-rich LEDs also causes the pupil in the eye to contract so while the sky appears darker, only a few of the brightest stars in the sky can be detected.
HONOURING THEIR COMMITMENT
All costs and losses, short and long-term to the community caused by street lighting must be taken into account. This is a commitment made by all Dunedin councillors in their support of the Ministry for Environment’s Urban Design Protocol which states, “the main quality of good urban design is custodianship: ensuring design is environmentally sustainable, safe and healthy.”
Our council has a responsibility and moral obligation to illuminate Dunedin as safely as possible with the least impact upon the people and environment entrusted to its care.
Until the true extent of the problem with blue light is acknowledged and solved, and the NZTA adds amber LEDs to their M-30 list of approved streetlights to enable co-funding, we need to very carefully consider our options.
• PC Amber LEDs have been developed to safely illuminate “ecologically sensitive” areas such as turtle breeding grounds - even though all human and wildlife habitats are in fact, “ecologically sensitive” to the negative effects of blue-rich light at night.
• PC Amber LEDs emit less blue and green wavelengths of light so they are warm, welcoming, and soft on the eyes - and unlike white blue-rich LEDs cause no visibility discomfort or disability glare.
• PC Amber LEDs emit less blue and green wavelengths of light so they are warm, welcoming, and soft on the eyes - and unlike white blue-rich LEDs cause no visibility discomfort or disability glare.
• PC Amber LEDs (2200K) have similar energy efficiency, and the same long lifespan, low maintenance, and technological advantages as white 3000K LEDs, but with less impact on human health and the environment, making them a more sensible and responsible option.
• Orange coloured streetlights have been used safely for over 60 years. There is no evidence to show white LEDs improve pedestrian and traffic safety, or reduce crime, nor has colour rendition been an issue prior to the lighting industry’s push for white LEDs.
• PC Amber LED streetlights are safe, smart, sustainable, and an intelligent and wise investment in the long-term wellbeing and economic health of Dunedin.
• Shielded HPS and/or PC Amber LEDs are also the best options for a Night Sky City, causing less 1/3 the skyglow of 4000K LEDs, and less than 1/2 the skyglow of 3000K LEDs.
http://www.flagstaffdarkskies.org/for-wonks/lamp-spectrum-light-pollution/
We petition the DCC to shield our existing nature-kind, night sky-friendly orange streetlights - and to delay the retrofit until safe, energy efficient PC Amber LEDs can be installed.
We petition the DCC to shield our existing nature-kind, night sky-friendly orange streetlights - and to delay the retrofit until safe, energy efficient PC Amber LEDs can be installed.
