Night maps

This study was founded on the belief that by capitalizing on the wealth and variety of raw data that we are able to collect, we can improve quality of life and personal safety in urban environments. We can work to achieve these positive changes by analysing and tweaking often neglected environmental parameters. The re-appropriation of urban spaces at nighttime was the goal of one of SPIN’s earliest projects—a survey of the artificial illumination across the city of Tallinn, Estonia. The first step of this pilot study was initiated in Tallinn by SPIN, in collaboration with the Politsei- ja Piirivalveamet (Police and Border Guard Board). In this study, we used a creative approach involving a custom-build device and an Arduino microcontroller to map public illumination. The device was carried throughout the city by car or bicycle (in restricted or less accessible areas) and measured light intensity at the darkest hour of the night over two weeks by means of digital luminosity sensors. GPS location, humidity, and temperature were also recorded. Using this data, we created a geographic representation of the illumination of public space in central Tallinn. While existing models map the placement of street lamps in order to predict public space illumination, our methods produce a more accurate representation of an individual’s perception. This is because other factors impacting luminosity: for instance, the height or shape of street lighting, or any obstructions. As a result, we demonstrated that a complete understanding of urban illumination requires measurements of luminosity at the ground level—where people walk, drive, and ride. At SPIN, one of our greatest concerns is accessibility: the degree to which an open space is available to as many different people as possible. To make accessibility a practical measure, we have devised ways to make it readily computable. In the case of Tallinn, we investigated whether the urban accessibility was related to street light intensity. In producing our ‘night maps,’ we found that the level of accessibility in urban spaces decreases with the distance from the city centre, and that this decrease is directly correlated with the level of public illumination. While this finding might seem obvious, it prompts an important question: can we improve accessibility by improving the quality of public illumination? Our research and subsequent night maps produced on this subject have important implications: firstly for crime prevention, but also for understanding the way that people perceive their city, its accessibility, and their integration within its urban spaces. This research has even further reaching implications beyond safety and accessibility. Based on our work on urban nighttime illumination, Sapienza University of Rome tasked SPIN with producing a report on the illumination inside and outside of the Colosseum, using similar techniques, in order to improve how the space it lit.