The Temporal Analysis of Light Pollution in Turkey using VIIRS data

TL;DR

This study analyzes the increase of artificial light pollution in Turkey from 2012 to 2020 using VIIRS satellite data, revealing an 80% rise in energy emitted to space and strong correlations with demographic factors.

Contribution

It provides the first comprehensive temporal analysis of Turkey's light pollution using VIIRS data and highlights the need for preventive legislation for dark sky preservation.

Findings

Total energy released to space increased by 80% from 2012 to 2019.

AL levels remained constant in Dark Sky Parks and rural areas.

Strong correlations between AL and demographic parameters like population and GDP.

Abstract

Artificial Light pollution (AL) in Turkey and in Turkish observatories between 2012--2020 have been studied using the archival data of Visible Infrared Imaging Radiometer Suite (VIIRS) instrument. The astroGIS database has been used in processing the data (https://www.astrogis.org) \cite{2020MNRAS.493.1204A}. The total energy released to space from Turkey increased by 80\% in 2019 with respect to 2012. In the span of the dataset, a steady and continuous increase has been observed throughout all cities of the country. On the other hand, Dark Sky Park locations, East and Southeast Anatolian regions and mostly rural areas around the cities kept their AL level constant. Four demographic parameters have been studied and they were found to be correlated very well with AL: Population ($R \simeq 0.90$); GDP ($R \simeq 0.87$); Total Power Consumption ($R \simeq 0.66$) and Outdoor Lightening ($R \simeq 0.67$). Contrary to countries acting to prevent AL increases, Turkey seems to be at the beginning of an era where AL will arithmetically increase throughout the country and enormous amount of energy will continuously escape to space and therefore will be wasted. Therefore, a preventive legislation, especially for invaluable astronomical site locations such as TURAG, TUG, DAG and \c{C}AAM where each is counted as a truly dark site due to their SQM values, has to be enacted in Turkey, in very near future.