Light pollution on the planet continues to rise, as confirmed by new results from a large-scale study conducted by an international group of scientists. In recent years, the rate of artificial lighting spread during nighttime has noticeably accelerated, although these changes are occurring unevenly across different regions of the world.
This is reported by Finway
Large-Scale Study of Satellite Images
Researchers analyzed over 1.16 million daily satellite images covering populated areas totaling approximately 3.51 million square kilometers. The lead authors of the study were Tian Li and Zhe Zhu from the Department of Natural Resources and the Environment at the University of Connecticut. They noted that despite the overall increase in the brightness of the night sky, local trends vary significantly.
From 2014 to 2022, the intensity of nighttime lighting increased by 16%, closely linked to population growth. However, on a more localized scale, the dynamics of change proved to be even more complex. Scientists found that brightness increased by 34% in some regions, while at the same time, a global decrease in brightness of 18% was recorded. Importantly, the nature of the changes varied: gradual changes were observed in 51% of the studied areas, sharp fluctuations in 14%, and both types of changes were simultaneously observed in 35%.
“According to our analysis, we noticed that in some regions, brightness is gradually increasing, in others it is decreasing, and some maintain stable levels, although even these places can change suddenly.”
Causes of Changes in Nighttime Lighting
The emergence of sharp changes in brightness, specialists note, may be linked to large-scale construction projects and infrastructure developments that are accompanied by intense lighting. At the same time, significant decreases in brightness are often associated with power supply disruptions, military conflicts, or other social upheavals.
Pixel-level analysis allowed scientists to gain a more detailed picture of changes in nighttime light in various corners of the planet. It turned out that the perception of a general increase in light pollution does not fully correspond to reality: individual, less populated or remote regions, as well as nature reserves, managed to maintain a stable level of nighttime lighting. However, even these places are not protected from sudden changes in the future.
The study emphasizes the need for ongoing monitoring and the development of strategies to mitigate the negative impact of light pollution, which threatens both astronomical observations and ecosystems.