A study published in Nature reveals that global light pollution increased by 16% in just nine years, even surpassing the growth of the world population. This increase is due to a 34% rise in some areas, offset by an 18% reduction in other areas that experienced darkening.
The research, led by the University of Connecticut with participation from NASA and the Helmholtz Centre Potsdam GFZ German Research Centre for Geosciences, used 1.16 million nighttime satellite images to create maps showing the dynamics and volatility of the human light footprint.
A heterogeneous phenomenon
The results show that light pollution does not grow uniformly:
- 51% of the studied area showed gradual changes linked to economic development and the transition to LED technologies.
- 20% of the zones experienced abrupt changes due to blackouts, social conflicts, or energy fluctuations.
- 35% of the territories experienced both types of variations. Only uninhabited regions or those with very limited development, such as natural reserves and remote deserts, maintained stable lighting conditions.
The role of LED technology
The adoption of LED lights has allowed for reduced brightness in areas that implemented them. In Europe, countries like Spain, France, the United Kingdom, and the Netherlands achieved an average reduction of 25%. Reductions were also observed in the East Coast and Midwest of the United States.
This technological change demonstrates that public policies and energy innovations can have a positive impact on reducing light pollution.
Environmental and social consequences
Light pollution directly affects biodiversity and human health. Artificial light alters sleep cycles, disorients nocturnal species, and changes the migration patterns of birds and insects. However, it remains a problem little perceived by society, as artificial light is associated with safety and progress.
Researcher Alicia Pelegrina, from the Institute of Astrophysics of Andalusia (IAA-CSIC), highlighted that the study is “solid and of great quality” and warns of the need to treat light pollution as a heterogeneous phenomenon in space and time. She also emphasized that this type of research is valuable for diagnosing the situation and guiding political decisions.
Light pollution is a global environmental problem that grows unevenly and dynamically. Although LED technology has proven to be an effective tool for reducing brightness in cities, the challenge remains to raise social awareness and implement policies that recognize artificial light as a polluting agent.
