Spread awareness to stop surplus light

What can we do about light pollution? Ruskin Hartley is the Executive Director of DarkSky International. Chris asked him what they're trying to achieve and what inspired him to take up this mantle…

Ruskin - I'd worked in conservation for the better part of 25 years, working on restoring ancient forests, trying to remove plastics from the ocean. I'll be honest, until five years ago, I hadn't really thought about light pollution as an issue, and as I came across it, I realised not only did it impact almost everything I cared about from a conservation perspective but, also, amongst issues I'd been tackling, it was one of the easiest to be solved.

Chris - You make it sound like there is a solution just waiting to be voiced then. So how do we tackle it?

Ruskin - Our organisation, Dark-Sky International, believes that the solution to light pollution actually comes from better quality lighting. This is not about turning off all the lights and plunging us into medieval darkness as some people like to say, but it is thinking about natural darkness as a precious resource. Light is something to be used sparingly and thoughtfully to meet our needs whilst mitigating the impact on wildlife, human health, climate, energy change, you name it. All those things that people care about.

Chris - I think also it's sort of ingrained into us, isn't it? That light equals good, dark equals bad, light combats crime, dark begets crime. And so it's a self-fulfilling prophecy, we put new houses up, we build new developments and new facilities, and they all come with a host of lights.

Ruskin - Yeah, many of the world's religions, the great books go back to that dichotomy of light and dark, right? So yes, it is there. Now, the reality is, until a little over a hundred years ago, and I think Newcastle was one of the first cities in the world to be lit with public streetlights, outside the world at night essentially was dark. And people were used to stepping outside at night and seeing the stars overhead unless it was cloudy. In fact, all of us were, in a sense, astronomers. We marked out the passage of time through the passage of the stars, and we have essentially lost that connection both to the natural world and to the stars overhead. And I think that has been a great loss, an immeasurable loss, to society. Now, today, 83% of people around the world live under light polluted skies. 99% in Europe and North America have lost that connection to the night sky because they live under light polluted skies.

Chris - Are you getting traction when you put your arguments to people who are policy makers, decision makers, are they receptive or do people say, look, this is a first world problem. We are grateful we've got some lighting.

Ruskin - I think it depends. It is always hard to answer those broad brush questions. We can answer it with specifics. There are certainly many communities, both large and small, who are starting to understand that light pollution is a real issue and better quality light can help deal with some of the other concerns of their community. Tucson, Arizona, where we are based, they are very protective of their dark skies because of the impact that has on the surrounding astronomy community. So when they upgraded their streetlights a number of years ago, they established from the very start that they wanted to both save energy by transitioning to more efficient LED based street lights but, at the same time, they wanted to make sure they mitigated and reduced light pollution. And by establishing those twin goals, they're able to save, I think it was 2 million US dollars per year in energy costs. And they also reduced light pollution as measured by the astronomers by 8%.

Chris - You mentioned LED lighting. While this is a game changer in efficiency terms because it's so much more efficient, you are wasting so much less electricity and turning more electricity into useful light rather than invisible heat, that people calculated that in fact they could have more lighting for less electricity spend because of LEDs and so, in fact, they increased and intensified the lighting. So it can be a double-edged sword.

Ruskin - That is absolutely right. Unfortunately, what has materialised is a great increase in light pollution as a result both by putting out more light and also changing the quality of the light that's put out there. We have essentially transitioned to a world where we're spewing far more short wavelength blue rich light at night into the environment than has ever been seen before. Essentially, every white LED streetlight out there is really a blue LED based street light with some clever chemistry so that we perceive them as white, but those blue rich emissions that are there are driving sky glow and are much more impactful on biology and so fundamentally changing the ecology of the night.

Chris - It sounds a bit from what you're saying, like the pill is a bit worse than the ill then with this, unless we're very careful?

Ruskin - Well, I think the trick is to be careful and I don't think the pill is worse than the ill. I think it's how much and how you're taking that. It's really about thinking about using it responsibly. Now, the good news about light emitting diode technology is they can be controlled. You can control both the direction of them through clever optics, you can control this underlying spectrum, the sort of colour, quality of the light, and you can dim them down and turn them off very quickly when they're not needed. So they have tremendous promise when they're used carefully. But if they're used without thought, the impact on the natural world can be tremendous.