The Fourth International Conference on Artificial Light at Night

The fourth international conference on Artificial Light at Night (ALAN) was held in Cluj-Napoca (Romania) from Sep. 26 to Sep. 28. The event was organized by the Technical University of Cluj-Napoca and the COST Action ES1204 LoNNe, Loss of the Night Network.

Since 2013 this event has drawn experts and scientists from all over the world -with 22 countries represented this year- to share experiences, best practices, and studies on artificial light at night and light pollution.

2016-09-26-10-37-21About 100 participants with a very diverse background, from lighting engineering to chronobiology, from environmental sciences to statistics, astrophysics and visual arts created an interdisciplinary melting pot.

During the three days it was possible to learn about the state of the art related to different aspects of artificial light at night. The conference sessions covered human health, technologies for light pollution monitoring, social aspects, ecology and promotion of nightscapes.

The talks spanned across different scales of observation: from very high detail experiments concerning micro-organism in streams, up to continental-scale assessment of light pollution.

Across this extremely diverse range of experiences and viewpoints, it was in fact possible to identify some common points.

All of the experts agree on the fact that artificial light at night is an essential resource to support our lives, from business to recreation, to safety and security.

2016-09-28-19-44-50At the same time, there are many cases where the negative effects of too much artificial light at night cannot be ignored. While many of these are in the process of being investigated, cautions should be taken against the proliferation of lighting systems which do not consider such aspects.

The technical guidelines created over the past fifteen years, following the first studies on light pollution, were primarily aimed at the reduction of upward lighting and of the number of luminaires.

With the growing presence of LED lighting, a new issue emerged: first-generation LEDs insured an extremely high efficiency (with energy savings up to 80%), while providing a light with a very high component of blue.

Many studies, proposed also at the ALAN conference, have re-iterated that the blue component in light has various negative effects, the main one being the suppression of melatonin production in many species.

Considering that a lighting system can have a life span of 15-20 years, and that in the coming years the replacement of millions of luminaires is foreseen all over the world, the challenge will be to install lighting systems which can provide the best trade-off between energy efficiency and impact on humans and on the living environment.

In this respect, innovation never stops, starting from the availability of new generations of LEDs, with a reduced emission of light in the blue part of the spectrum (with a colour temperature around 3000K).

While many norms and guidelines have not yet completely accounted for such innovations, it is important that all the stakeholders involved in lighting (technicians, administrator, and citizens) be aware of the negative effects of too much artificial light at night, and of the solutions to counter such effects.

The ALAN conference also had the participation from Italian specialists. These included some young researchers (mostly active outside of Italy), and a joint presentation by the BuioMetria Partecipativa project with the National Research Council’s Biometeorology Institute. The presentation summarized various awareness raising and data collection efforts taking place since 2008, in Italy and abroad (see POSTER).

After the first four editions, the ALAN conference will be switching to a bi-annual schedule. The next edition is expected to take place in the USA in 2018.

The abstracts of the Cluj-Napoca conference are available in PDF format.

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