Convergence between Increased Light Pollution and Urban Sprawl Dynamic in Poland (2012–2022)

Urban sprawl is a nuisance – both economically and ecologically speaking. Among the causes of this nuisance is light pollution; both the scale of the light pollution and the spatial expansion of suburbs in Poland increased significantly during the period 2012–2022. The most significant light pollution occurs in urbanized areas in general; however, the scattered developments of suburbs make the problem of light pollution in these areas disproportionate to the population density as compared to cities. The research that is described below analyzed changes in the amounts of light that were emitted into the sky (radiance) as were calculated on the basis of observational data from the Suomi NPP meteorological satellite as well as housing production dynamics. Data regarding both radiance and housing production was acquired for communes and then aggregated to larger areas depending on the urban, suburban, or rural character of each commune. Then, the agglomeration areas were analyzed – distinguishing between urban centers and non-urban agglomeration areas (suburbs). Two convergence indices were analyzed: Spearman’s rank correlation coefficient, and coefficient of determination R2. It turns out that, in suburban areas, both indices returned much higher convergence rates between light pollution and housing construction than in the cases of the cities. The causes of this phenomenon need further research; nevertheless, two possible top-down solutions of this problem may be lighting masterplans and the modernization of lighting fixtures.