Title: Cloud Coverage Acts as an Amplifier for Ecological Light Pollution in Urban Ecosystems Authors: Christopher C. M. Kyba, Thomas Ruhtz, Jürgen Fischer, Franz Hölker
The diurnal cycle of light and dark is one of the strongest environmental factors for life on Earth. Many species in both terrestrial and aquatic ecosystems use the level of ambient light to regulate their metabolism, growth, and behaviour. The sky glow caused by artificial lighting from urban areas disrupts this natural cycle, and has been shown to impact the behaviour of organisms, even many kilometres away from the light sources. It could be hypothesised that factors that increase the luminance of the sky amplify the degree of this "ecological light pollution". We show that cloud coverage dramatically amplifies the sky luminance, by a factor of 10.1 for one location inside of Berlin and by a factor of 2.8 at 32 km from the city centre. We also show that inside of the city overcast nights are brighter than clear rural moonlit nights, by a factor of 4.1. These results have important implications for choronobiological and chronoecological studies in urban areas, where this amplification effect has previously not been considered.
A Nottinghamshire astronomer has called on the public to help reduce light pollution within the county. Phil Randall, from the Mansfield and Sutton Astronomical Society, said it is an increasing problem. Read more
You've heard of noise pollution and visual pollution, but what about light pollution? Local astronomers say it's a big problem. Amateur Astronomer Mark Eburne says 30-40 per cent of the light pollution obscuring our view comes from streetlights. Read more
Night sky needs protection from Vancouver's lights, astronomer says
Mark Eburne laments the fact that he has to get away from the city to really see the stars with the naked eye. The amateur astronomer says the bright lights of Vancouver are drowning out the night sky. Read more
Artificial light at night can disrupt everything from astronomers' views of the stars to the path-finding abilities of migrating animals. The impacts of artificial light on wildlife was the focus of a symposium at the 24th annual International Congress for Conservation Biology, held 3-7 July in Edmonton, Alberta. Read more
The sun has set on Peter Lowe's stargazing, at least from his Langwarrin home. The current president and last remaining founding member of the Mornington Peninsula Astronomical Society can no longer observe the night skies through his powerful fixed telescope after the duplication of Cranbourne Rd. His Grain Store Court property backs on to Cranbourne Rd and its brilliant street lighting. But it's far from brilliant for Mr Lowe, who built a home observatory in his backyard 10 years ago and installed a $10,000 Celestron 11 telescope. Read more
I recently took a whitewater rafting trip in the Dinosaur National Monument in Colorado. We saw skies that were especially dark, clear and steady. It got me thinking about how the growth of our cities has changed how we see the sky. Those of us living in the western United States generally take our dark skies for granted. Yet light pollution is an increasing problem, even in the remote West. Read more
Welsh Assembly Debates Blinded by the Light: Dark Skies in Wales
Wales's night sky required protection, AMs heard today. The Welsh National Assembly today debated the effects of light pollution and proposals for how the problem could be alleviated. Read more
There's one problem with Urban astronomy, and it's a big one. It is the reason so many historical observatories, places where great discoveries were made and the foundations of modern astronomy were set down, have been shut down and even demolished. That problem is light. Modern cities pump so much light into the sky that many of us have never actually seen a night sky at all. Ask somebody what colour the sky is at night and they'll confidently assert "Black, of course!". Which just goes to show when last they actually looked up. The night sky in the city is navy blue in the suburbs, and dull orange in the city proper, and shines bright enough to completely extinguish all but a handful of the brightest stars. If we happen to glance up, we see nothing at all. The sky is boring, and not worth watching. Read more