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arXiv · 2510.05105

Land use and anisotropy of artificial light observed by night time satellite

Kai Pong Tong
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Abstract

Upward emission of artificial light has been investigated by researchers since the commissioning of the Visible/Infrared Imaging Radiometer Suite (VIIRS) Day/Night Band (DNB) in 2011, with applications ranging from night time light mapping to quantifying socio-economical development. The wide swath of the VIIRS-DNB sensor enables detection of artificial light at multiple angles and was utilized to study emission of artificial light from cities at different angles as well as atmospheric properties. Existing studies of the relationship between the directionality and land surface features are not available for most of the Earth's surface due to the use of space-borne LiDAR as a source of proxy. To solve this problem, we compared the land use data published under the Coordination of Information on the Environment (CORINE) against the fit parameters of radiance of upward artificial light. In general, the quadratic term of the fit, which quantifies how the brightness changes when viewing closer from the horizon at a point on the Earth, is negative when the area is "Continuous urban fabric" or "Sparsely vegetated areas", and vice versa for all other investigated land use classes. However the quadratic term shifts towards negative values for brighter areas. These results indicate that while densely built areas emit more light towards the zenith than sideways, the VIIRS-DNB is unable to distinguish small densely built areas scattered around larger unbuilt areas. Therefore, sensors with higher spatial resolution will be required to resolve the light emission patterns of areas with complicated combinations of land uses.

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Kai Pong Tong. 2025-09-20. Land use and anisotropy of artificial light observed by night time satellite. https://arxiv.org/abs/2510.05105

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