Science - October 27, 2005

Would someone turn the light out?

Along with Belgium and Puerto Rico, the Netherlands is the most illuminated country in the world. Alterra carried out research on how people experience the large amounts of light emitted by greenhouses, cars and street lamps at night. People find it annoying, but also necessary, as they believe that lighting makes the streets safer.

Coming Saturday (29 October) The Netherlands Society for Nature and Environment is holding the Night of the Night (Nacht van de Nacht) as part of its campaign against light pollution in the Netherlands. This conservation organisation wants the nights to become darker, because the large amount of light irritates humans and disturbs wildlife.

Fransje Langers of Alterra did research for Nature and Environment on how the Dutch experience the dark. Her results can be found in a book intended for the general public, Schitterend donker (Brilliant darkness), which explains the effects of light. The Dutch are more familiar with rosy coloured clouds in the night sky than pitch dark nights. The worst culprits are the greenhouses that emit light upwards, which is then reflected back by the clouds. The lamps that are used for football stadiums and lighting along the motorways also make the night sky lighter.

Langers’ research indicates that many people think that street lighting increases traffic safety. But this is not always the case, according to research done by the ministry of public works. There are more accidents along illuminated highways than on darker roads, because people drive faster when roads are lit up. At other locations, such as crossroads, however street lighting does improve road safety.

From the survey that Langers carried out it emerged that people focus far more on the advantages of light. Eighty percent of the population thinks that lighting makes their surroundings safer, in particular on the street in urban areas, for traffic and burglary prevention. People also like atmospheric lighting. On the other hand, people prefer it to be dark in the immediate surroundings where they live so that they can appreciate the beauty of a dark night. After the survey, Langers also interviewed people to gain a better idea of how individuals experience darkness and artificial light.

From the interviews it emerged that people in towns want light, and in the countryside they want darkness. A dark night is regarded as the right ending to a hectic day. Only once it gets dark can they actually unwind. Many people regret that it is so difficult to see stars at night in the Netherlands as a result of light pollution and they also regard it as unnatural that the nights are no longer completely dark. / JT

On www.laathetdonkerdonker.nl you can search (in Dutch) by province for activities organised on 29 October.

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