International Journal of Sustainable Lighting

An enhanced version of the Gaia map of the brightness of the natural sky

Eduard Masana, Salva Bará, Josep Manel Carrasco, Salvador José Ribas — Wed, 30 Mar 2022 00:00:00 +0000

The GAia Map of the Brightness Of the Natural Sky (GAMBONS) is a model to map the natural night brightness of the sky in cloudless and moonless nights. It computes the star radiance from the photometric data in Gaia and Hipparcos catalogues, adding the contributions of the diffuse galactic and extragalactic light, zodiacal light and airglow, and taking into account the effects of atmospheric attenuation and scattering. The model allows computing the natural sky brightness in any given photometric band for a ground-based observer, if appropriate transformations from the Gaia bands are available. In this work we present the most recent improvements of the model, including the use of Gaia EDR3 data, the inclusion of a wide set of photometric bands and the derivation of additional sky brightness indicators, as the horizontal irradiance and the average hemispheric radiance.

The Biological Effects of Light Pollution on Terrestrial and Marine Organisms

Octavia Brayley, Dr Martin How, Dr Andrew Wakefield — Wed, 30 Mar 2022 00:00:00 +0000

Humans first began using artificial light at night (ALAN) during the industrial revolution and sources of light have diversified and intensified considerably over the last century. Light pollution has previously been defined under two separate branches, “ecological light pollution” where the natural light patterns are altered in marine and terrestrial environments, and “astronomical light pollution” where the view of the night sky is reduced. Natural light is vital for the regulation of animal behaviour and interactions. Surprisingly, this environmental stressor did not become a worldwide concern until 2009. Since then, research into this subject has substantially increased, with studies highlighting the detrimental effects of ALAN. These effects can be serious for many organisms and include the disruption of the essential circadian rhythms that most organisms use to time important behaviours such as foraging, reproduction, and sleep. Whether all organisms possess phenotypic plasticity to effectively adapt to increasing and changing artificial light pollution is not yet known. Here, we summarise the effects of light pollution among many different species, from marine to terrestrial, with a focus on the areas that require further research to enhance our knowledge of this subject. The aim of this review is to raise awareness and enhance understanding about this little-discussed environmental concern, including some novel ideas on camouflage and polarised light pollution, hopefully encouraging future research into the effects of light pollution on organism behaviour.

The Scale and Impact of Sports Stadium Grow Lighting Systems In England

Steve Geliot, Jacqueline Coesfeld, Christopher C. M. Kyba — Wed, 29 Jun 2022 00:00:00 +0000

Recently, many sports stadiums have begun using high power lighting systems to help the grass grow on the playing surfaces. These lights supplement winter sunlight, which is sometimes insufficient due to the low elevation of the sun and shading from the surrounding walls. In many stadiums, grow lights are operated at night, and the waste light emissions from these stadiums are extraordinary in comparison to most other areas in the cities in which they are located. Here we present space-based observations of the radiance of fourteen stadiums located in towns and cities of varying sizes and in varying geographical locations across England which each have a Premier League football stadium. We show that stadiums have dramatically brightened (typically by factors of 2-5) in recent years compared to the situation in 2012. We also show that stadiums are often responsible for an important fraction of the total light emission of the cities they are in (often 10% or more, and in one case up to 30%). Because the light emissions from many English towns have been reducing in recent years, the overall fraction of light due to the stadiums is increasing. In some cases, total city emissions have actually increased due to the stadiums, undermining the environmental impact of reductions in radiance in the rest of the community. We believe that stadium grow lights are an excellent target for sustainable lighting initiatives, both because of their considerable environmental impact (especially when located near sensitive areas) and the possibility of high profile and successful waste light mitigation projects.