Are population-based models advantageous in estimating the lumen outputs from light-pollution sources?

Abstract

Abstract The total lumen output (TLO) from ground-based artificial light sources is required in a wide range of light-pollution models currently in use. No realistic assessment of diffuse light levels in the nocturnal environment is possible if the information on TLO is missing. Traditional approaches to skyglow modelling, if no lighting inventory is available, foresee to estimate TLO based on population and average amount of lumens per capita. However, we show in this letter that a model based on the area of artificially lit surfaces can reduce uncertainties in estimating TLO by 25 per cent for compact urban areas of defined centres and autonomous character and even 50 per cent for diffuse cities with small satellite towns interacting closely with the main city. The new model could be of great significance to the community of light-pollution researchers, especially astronomers, physicists, and modellers who use TLO routinely in light-pollution characterization.