An Overview of the Cognitive and Biological Effects of City Nighttime Illumination Including a London Case Study

Current scientific research demonstrates how critical the effects of city nighttime illumination are upon cognitive and biological health – which needs to be adequately acknowledged, understood and addressed by conscious cities and the plans they develop. Until recent decades, the design of nighttime lighting was determined mostly by electrical engineers who often applied technical standards to meet the requirements of vehicle-focused cities. Unfortunately, consideration of pedestrians and their visual needs to navigate throughout urbanscapes at night were ignored, and so too, was the impact that artificial lighting might have on them, and the environment. Today, the majority of urban city lighting has been installed without full awareness of its impact, and as a result, artificial light at night (ALAN) and light pollution have become an obvious public nuisance, a health risk and an environmental burden. While poor lighting has its drawbacks, a lack of lighting can have many positive aspects, and urban settings can benefit from protecting, preserving and promoting natural darkness. We present two recent planning and design initiatives of London, in the UK, where the quality of light and value of darkness were not given the degree of attention and consideration they deserve. This paper has particular relevance for urban policy makers, city planners, architects, designers, consultants and researchers as it explores the various problems caused by the obvious lack of responsible nighttime illumination.